For text that will be edited, use a {@link DynamicLayout}, * which will be updated as the text changes. * For text that will not change, use a {@link StaticLayout}. */ public abstract class Layout { /** @hide */ @IntDef(prefix = { "BREAK_STRATEGY_" }, value = { LineBreaker.BREAK_STRATEGY_SIMPLE, LineBreaker.BREAK_STRATEGY_HIGH_QUALITY, LineBreaker.BREAK_STRATEGY_BALANCED }) @Retention(RetentionPolicy.SOURCE) public @interface BreakStrategy {} /** * Value for break strategy indicating simple line breaking. Automatic hyphens are not added * (though soft hyphens are respected), and modifying text generally doesn't affect the layout * before it (which yields a more consistent user experience when editing), but layout may not * be the highest quality. */ public static final int BREAK_STRATEGY_SIMPLE = LineBreaker.BREAK_STRATEGY_SIMPLE; /** * Value for break strategy indicating high quality line breaking, including automatic * hyphenation and doing whole-paragraph optimization of line breaks. */ public static final int BREAK_STRATEGY_HIGH_QUALITY = LineBreaker.BREAK_STRATEGY_HIGH_QUALITY; /** * Value for break strategy indicating balanced line breaking. The breaks are chosen to * make all lines as close to the same length as possible, including automatic hyphenation. */ public static final int BREAK_STRATEGY_BALANCED = LineBreaker.BREAK_STRATEGY_BALANCED; /** @hide */ @IntDef(prefix = { "HYPHENATION_FREQUENCY_" }, value = { HYPHENATION_FREQUENCY_NORMAL, HYPHENATION_FREQUENCY_NORMAL_FAST, HYPHENATION_FREQUENCY_FULL, HYPHENATION_FREQUENCY_FULL_FAST, HYPHENATION_FREQUENCY_NONE }) @Retention(RetentionPolicy.SOURCE) public @interface HyphenationFrequency {} /** * Value for hyphenation frequency indicating no automatic hyphenation. Useful * for backward compatibility, and for cases where the automatic hyphenation algorithm results * in incorrect hyphenation. Mid-word breaks may still happen when a word is wider than the * layout and there is otherwise no valid break. Soft hyphens are ignored and will not be used * as suggestions for potential line breaks. */ public static final int HYPHENATION_FREQUENCY_NONE = 0; /** * Value for hyphenation frequency indicating a light amount of automatic hyphenation, which * is a conservative default. Useful for informal cases, such as short sentences or chat * messages. */ public static final int HYPHENATION_FREQUENCY_NORMAL = 1; /** * Value for hyphenation frequency indicating the full amount of automatic hyphenation, typical * in typography. Useful for running text and where it's important to put the maximum amount of * text in a screen with limited space. */ public static final int HYPHENATION_FREQUENCY_FULL = 2; /** * Value for hyphenation frequency indicating a light amount of automatic hyphenation with * using faster algorithm. * * This option is useful for informal cases, such as short sentences or chat messages. To make * text rendering faster with hyphenation, this algorithm ignores some hyphen character related * typographic features, e.g. kerning. */ public static final int HYPHENATION_FREQUENCY_NORMAL_FAST = 3; /** * Value for hyphenation frequency indicating the full amount of automatic hyphenation with * using faster algorithm. * * This option is useful for running text and where it's important to put the maximum amount of * text in a screen with limited space. To make text rendering faster with hyphenation, this * algorithm ignores some hyphen character related typographic features, e.g. kerning. */ public static final int HYPHENATION_FREQUENCY_FULL_FAST = 4; private static final ParagraphStyle[] NO_PARA_SPANS = ArrayUtils.emptyArray(ParagraphStyle.class); /** @hide */ @IntDef(prefix = { "JUSTIFICATION_MODE_" }, value = { LineBreaker.JUSTIFICATION_MODE_NONE, LineBreaker.JUSTIFICATION_MODE_INTER_WORD }) @Retention(RetentionPolicy.SOURCE) public @interface JustificationMode {} /** * Value for justification mode indicating no justification. */ public static final int JUSTIFICATION_MODE_NONE = LineBreaker.JUSTIFICATION_MODE_NONE; /** * Value for justification mode indicating the text is justified by stretching word spacing. */ public static final int JUSTIFICATION_MODE_INTER_WORD = LineBreaker.JUSTIFICATION_MODE_INTER_WORD; /* * Line spacing multiplier for default line spacing. */ public static final float DEFAULT_LINESPACING_MULTIPLIER = 1.0f; /* * Line spacing addition for default line spacing. */ public static final float DEFAULT_LINESPACING_ADDITION = 0.0f; /** * Strategy which considers a text segment to be inside a rectangle area if the segment bounds * intersect the rectangle. */ @NonNull public static final TextInclusionStrategy INCLUSION_STRATEGY_ANY_OVERLAP = RectF::intersects; /** * Strategy which considers a text segment to be inside a rectangle area if the center of the * segment bounds is inside the rectangle. */ @NonNull public static final TextInclusionStrategy INCLUSION_STRATEGY_CONTAINS_CENTER = (segmentBounds, area) -> area.contains(segmentBounds.centerX(), segmentBounds.centerY()); /** * Strategy which considers a text segment to be inside a rectangle area if the segment bounds * are completely contained within the rectangle. */ @NonNull public static final TextInclusionStrategy INCLUSION_STRATEGY_CONTAINS_ALL = (segmentBounds, area) -> area.contains(segmentBounds); /** * Return how wide a layout must be in order to display the specified text with one line per * paragraph. * *
As of O, Uses * {@link TextDirectionHeuristics#FIRSTSTRONG_LTR} as the default text direction heuristics. In * the earlier versions uses {@link TextDirectionHeuristics#LTR} as the default.
*/ public static float getDesiredWidth(CharSequence source, TextPaint paint) { return getDesiredWidth(source, 0, source.length(), paint); } /** * Return how wide a layout must be in order to display the specified text slice with one * line per paragraph. * *As of O, Uses * {@link TextDirectionHeuristics#FIRSTSTRONG_LTR} as the default text direction heuristics. In * the earlier versions uses {@link TextDirectionHeuristics#LTR} as the default.
*/ public static float getDesiredWidth(CharSequence source, int start, int end, TextPaint paint) { return getDesiredWidth(source, start, end, paint, TextDirectionHeuristics.FIRSTSTRONG_LTR); } /** * Return how wide a layout must be in order to display the * specified text slice with one line per paragraph. * * @hide */ public static float getDesiredWidth(CharSequence source, int start, int end, TextPaint paint, TextDirectionHeuristic textDir) { return getDesiredWidthWithLimit(source, start, end, paint, textDir, Float.MAX_VALUE); } /** * Return how wide a layout must be in order to display the * specified text slice with one line per paragraph. * * If the measured width exceeds given limit, returns limit value instead. * @hide */ public static float getDesiredWidthWithLimit(CharSequence source, int start, int end, TextPaint paint, TextDirectionHeuristic textDir, float upperLimit) { float need = 0; int next; for (int i = start; i <= end; i = next) { next = TextUtils.indexOf(source, '\n', i, end); if (next < 0) next = end; // note, omits trailing paragraph char float w = measurePara(paint, source, i, next, textDir); if (w > upperLimit) { return upperLimit; } if (w > need) need = w; next++; } return need; } /** * Subclasses of Layout use this constructor to set the display text, * width, and other standard properties. * @param text the text to render * @param paint the default paint for the layout. Styles can override * various attributes of the paint. * @param width the wrapping width for the text. * @param align whether to left, right, or center the text. Styles can * override the alignment. * @param spacingMult factor by which to scale the font size to get the * default line spacing * @param spacingAdd amount to add to the default line spacing */ protected Layout(CharSequence text, TextPaint paint, int width, Alignment align, float spacingMult, float spacingAdd) { this(text, paint, width, align, TextDirectionHeuristics.FIRSTSTRONG_LTR, spacingMult, spacingAdd); } /** * Subclasses of Layout use this constructor to set the display text, * width, and other standard properties. * @param text the text to render * @param paint the default paint for the layout. Styles can override * various attributes of the paint. * @param width the wrapping width for the text. * @param align whether to left, right, or center the text. Styles can * override the alignment. * @param spacingMult factor by which to scale the font size to get the * default line spacing * @param spacingAdd amount to add to the default line spacing * * @hide */ protected Layout(CharSequence text, TextPaint paint, int width, Alignment align, TextDirectionHeuristic textDir, float spacingMult, float spacingAdd) { if (width < 0) throw new IllegalArgumentException("Layout: " + width + " < 0"); // Ensure paint doesn't have baselineShift set. // While normally we don't modify the paint the user passed in, // we were already doing this in Styled.drawUniformRun with both // baselineShift and bgColor. We probably should reevaluate bgColor. if (paint != null) { paint.bgColor = 0; paint.baselineShift = 0; } mText = text; mPaint = paint; mWidth = width; mAlignment = align; mSpacingMult = spacingMult; mSpacingAdd = spacingAdd; mSpannedText = text instanceof Spanned; mTextDir = textDir; } /** @hide */ protected void setJustificationMode(@JustificationMode int justificationMode) { mJustificationMode = justificationMode; } /** * Replace constructor properties of this Layout with new ones. Be careful. */ /* package */ void replaceWith(CharSequence text, TextPaint paint, int width, Alignment align, float spacingmult, float spacingadd) { if (width < 0) { throw new IllegalArgumentException("Layout: " + width + " < 0"); } mText = text; mPaint = paint; mWidth = width; mAlignment = align; mSpacingMult = spacingmult; mSpacingAdd = spacingadd; mSpannedText = text instanceof Spanned; } /** * Draw this Layout on the specified Canvas. * * This API draws background first, then draws text on top of it. * * @see #draw(Canvas, List, List, Path, Paint, int) */ public void draw(Canvas c) { draw(c, (Path) null, (Paint) null, 0); } /** * Draw this Layout on the specified canvas, with the highlight path drawn * between the background and the text. * * @param canvas the canvas * @param selectionHighlight the path of the selection highlight or cursor; can be null * @param selectionHighlightPaint the paint for the selection highlight * @param cursorOffsetVertical the amount to temporarily translate the * canvas while rendering the highlight * * @see #draw(Canvas, List, List, Path, Paint, int) */ public void draw( Canvas canvas, Path selectionHighlight, Paint selectionHighlightPaint, int cursorOffsetVertical) { draw(canvas, null, null, selectionHighlight, selectionHighlightPaint, cursorOffsetVertical); } /** * Draw this layout on the specified canvas. * * This API draws background first, then draws highlight paths on top of it, then draws * selection or cursor, then finally draws text on top of it. * * @see #drawBackground(Canvas) * @see #drawText(Canvas) * * @param canvas the canvas * @param highlightPaths the path of the highlights. The highlightPaths and highlightPaints must * have the same length and aligned in the same order. For example, the * paint of the n-th of the highlightPaths should be stored at the n-th of * highlightPaints. * @param highlightPaints the paints for the highlights. The highlightPaths and highlightPaints * must have the same length and aligned in the same order. For example, * the paint of the n-th of the highlightPaths should be stored at the * n-th of highlightPaints. * @param selectionPath the selection or cursor path * @param selectionPaint the paint for the selection or cursor. * @param cursorOffsetVertical the amount to temporarily translate the canvas while rendering * the highlight */ public void draw(@NonNull Canvas canvas, @Nullable ListNOTE: this is inadequate to support bidirectional text, and will change. */ public abstract Directions getLineDirections(int line); /** * Returns the (negative) number of extra pixels of ascent padding in the * top line of the Layout. */ public abstract int getTopPadding(); /** * Returns the number of extra pixels of descent padding in the * bottom line of the Layout. */ public abstract int getBottomPadding(); /** * Returns the start hyphen edit for a line. * * @hide */ public @Paint.StartHyphenEdit int getStartHyphenEdit(int line) { return Paint.START_HYPHEN_EDIT_NO_EDIT; } /** * Returns the end hyphen edit for a line. * * @hide */ public @Paint.EndHyphenEdit int getEndHyphenEdit(int line) { return Paint.END_HYPHEN_EDIT_NO_EDIT; } /** * Returns the left indent for a line. * * @hide */ public int getIndentAdjust(int line, Alignment alignment) { return 0; } /** * Return true if the fallback line space is enabled in this Layout. * * @return true if the fallback line space is enabled. Otherwise returns false. */ public boolean isFallbackLineSpacingEnabled() { return false; } /** * Returns true if the character at offset and the preceding character * are at different run levels (and thus there's a split caret). * @param offset the offset * @return true if at a level boundary * @hide */ @UnsupportedAppUsage public boolean isLevelBoundary(int offset) { int line = getLineForOffset(offset); Directions dirs = getLineDirections(line); if (dirs == DIRS_ALL_LEFT_TO_RIGHT || dirs == DIRS_ALL_RIGHT_TO_LEFT) { return false; } int[] runs = dirs.mDirections; int lineStart = getLineStart(line); int lineEnd = getLineEnd(line); if (offset == lineStart || offset == lineEnd) { int paraLevel = getParagraphDirection(line) == 1 ? 0 : 1; int runIndex = offset == lineStart ? 0 : runs.length - 2; return ((runs[runIndex + 1] >>> RUN_LEVEL_SHIFT) & RUN_LEVEL_MASK) != paraLevel; } offset -= lineStart; for (int i = 0; i < runs.length; i += 2) { if (offset == runs[i]) { return true; } } return false; } /** * Returns true if the character at offset is right to left (RTL). * @param offset the offset * @return true if the character is RTL, false if it is LTR */ public boolean isRtlCharAt(int offset) { int line = getLineForOffset(offset); Directions dirs = getLineDirections(line); if (dirs == DIRS_ALL_LEFT_TO_RIGHT) { return false; } if (dirs == DIRS_ALL_RIGHT_TO_LEFT) { return true; } int[] runs = dirs.mDirections; int lineStart = getLineStart(line); for (int i = 0; i < runs.length; i += 2) { int start = lineStart + runs[i]; int limit = start + (runs[i+1] & RUN_LENGTH_MASK); if (offset >= start && offset < limit) { int level = (runs[i+1] >>> RUN_LEVEL_SHIFT) & RUN_LEVEL_MASK; return ((level & 1) != 0); } } // Should happen only if the offset is "out of bounds" return false; } /** * Returns the range of the run that the character at offset belongs to. * @param offset the offset * @return The range of the run * @hide */ public long getRunRange(int offset) { int line = getLineForOffset(offset); Directions dirs = getLineDirections(line); if (dirs == DIRS_ALL_LEFT_TO_RIGHT || dirs == DIRS_ALL_RIGHT_TO_LEFT) { return TextUtils.packRangeInLong(0, getLineEnd(line)); } int[] runs = dirs.mDirections; int lineStart = getLineStart(line); for (int i = 0; i < runs.length; i += 2) { int start = lineStart + runs[i]; int limit = start + (runs[i+1] & RUN_LENGTH_MASK); if (offset >= start && offset < limit) { return TextUtils.packRangeInLong(start, limit); } } // Should happen only if the offset is "out of bounds" return TextUtils.packRangeInLong(0, getLineEnd(line)); } /** * Checks if the trailing BiDi level should be used for an offset * * This method is useful when the offset is at the BiDi level transition point and determine * which run need to be used. For example, let's think about following input: (L* denotes * Left-to-Right characters, R* denotes Right-to-Left characters.) * Input (Logical Order): L1 L2 L3 R1 R2 R3 L4 L5 L6 * Input (Display Order): L1 L2 L3 R3 R2 R1 L4 L5 L6 * * Then, think about selecting the range (3, 6). The offset=3 and offset=6 are ambiguous here * since they are at the BiDi transition point. In Android, the offset is considered to be * associated with the trailing run if the BiDi level of the trailing run is higher than of the * previous run. In this case, the BiDi level of the input text is as follows: * * Input (Logical Order): L1 L2 L3 R1 R2 R3 L4 L5 L6 * BiDi Run: [ Run 0 ][ Run 1 ][ Run 2 ] * BiDi Level: 0 0 0 1 1 1 0 0 0 * * Thus, offset = 3 is part of Run 1 and this method returns true for offset = 3, since the BiDi * level of Run 1 is higher than the level of Run 0. Similarly, the offset = 6 is a part of Run * 1 and this method returns false for the offset = 6 since the BiDi level of Run 1 is higher * than the level of Run 2. * * @returns true if offset is at the BiDi level transition point and trailing BiDi level is * higher than previous BiDi level. See above for the detail. * @hide */ @VisibleForTesting public boolean primaryIsTrailingPrevious(int offset) { int line = getLineForOffset(offset); int lineStart = getLineStart(line); int lineEnd = getLineEnd(line); int[] runs = getLineDirections(line).mDirections; int levelAt = -1; for (int i = 0; i < runs.length; i += 2) { int start = lineStart + runs[i]; int limit = start + (runs[i+1] & RUN_LENGTH_MASK); if (limit > lineEnd) { limit = lineEnd; } if (offset >= start && offset < limit) { if (offset > start) { // Previous character is at same level, so don't use trailing. return false; } levelAt = (runs[i+1] >>> RUN_LEVEL_SHIFT) & RUN_LEVEL_MASK; break; } } if (levelAt == -1) { // Offset was limit of line. levelAt = getParagraphDirection(line) == 1 ? 0 : 1; } // At level boundary, check previous level. int levelBefore = -1; if (offset == lineStart) { levelBefore = getParagraphDirection(line) == 1 ? 0 : 1; } else { offset -= 1; for (int i = 0; i < runs.length; i += 2) { int start = lineStart + runs[i]; int limit = start + (runs[i+1] & RUN_LENGTH_MASK); if (limit > lineEnd) { limit = lineEnd; } if (offset >= start && offset < limit) { levelBefore = (runs[i+1] >>> RUN_LEVEL_SHIFT) & RUN_LEVEL_MASK; break; } } } return levelBefore < levelAt; } /** * Computes in linear time the results of calling * #primaryIsTrailingPrevious for all offsets on a line. * @param line The line giving the offsets we compute the information for * @return The array of results, indexed from 0, where 0 corresponds to the line start offset * @hide */ @VisibleForTesting public boolean[] primaryIsTrailingPreviousAllLineOffsets(int line) { int lineStart = getLineStart(line); int lineEnd = getLineEnd(line); int[] runs = getLineDirections(line).mDirections; boolean[] trailing = new boolean[lineEnd - lineStart + 1]; byte[] level = new byte[lineEnd - lineStart + 1]; for (int i = 0; i < runs.length; i += 2) { int start = lineStart + runs[i]; int limit = start + (runs[i + 1] & RUN_LENGTH_MASK); if (limit > lineEnd) { limit = lineEnd; } if (limit == start) { continue; } level[limit - lineStart - 1] = (byte) ((runs[i + 1] >>> RUN_LEVEL_SHIFT) & RUN_LEVEL_MASK); } for (int i = 0; i < runs.length; i += 2) { int start = lineStart + runs[i]; byte currentLevel = (byte) ((runs[i + 1] >>> RUN_LEVEL_SHIFT) & RUN_LEVEL_MASK); trailing[start - lineStart] = currentLevel > (start == lineStart ? (getParagraphDirection(line) == 1 ? 0 : 1) : level[start - lineStart - 1]); } return trailing; } /** * Get the primary horizontal position for the specified text offset. * This is the location where a new character would be inserted in * the paragraph's primary direction. */ public float getPrimaryHorizontal(int offset) { return getPrimaryHorizontal(offset, false /* not clamped */); } /** * Get the primary horizontal position for the specified text offset, but * optionally clamp it so that it doesn't exceed the width of the layout. * @hide */ @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) public float getPrimaryHorizontal(int offset, boolean clamped) { boolean trailing = primaryIsTrailingPrevious(offset); return getHorizontal(offset, trailing, clamped); } /** * Get the secondary horizontal position for the specified text offset. * This is the location where a new character would be inserted in * the direction other than the paragraph's primary direction. */ public float getSecondaryHorizontal(int offset) { return getSecondaryHorizontal(offset, false /* not clamped */); } /** * Get the secondary horizontal position for the specified text offset, but * optionally clamp it so that it doesn't exceed the width of the layout. * @hide */ @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553) public float getSecondaryHorizontal(int offset, boolean clamped) { boolean trailing = primaryIsTrailingPrevious(offset); return getHorizontal(offset, !trailing, clamped); } private float getHorizontal(int offset, boolean primary) { return primary ? getPrimaryHorizontal(offset) : getSecondaryHorizontal(offset); } private float getHorizontal(int offset, boolean trailing, boolean clamped) { int line = getLineForOffset(offset); return getHorizontal(offset, trailing, line, clamped); } private float getHorizontal(int offset, boolean trailing, int line, boolean clamped) { int start = getLineStart(line); int end = getLineEnd(line); int dir = getParagraphDirection(line); boolean hasTab = getLineContainsTab(line); Directions directions = getLineDirections(line); TabStops tabStops = null; if (hasTab && mText instanceof Spanned) { // Just checking this line should be good enough, tabs should be // consistent across all lines in a paragraph. TabStopSpan[] tabs = getParagraphSpans((Spanned) mText, start, end, TabStopSpan.class); if (tabs.length > 0) { tabStops = new TabStops(TAB_INCREMENT, tabs); // XXX should reuse } } TextLine tl = TextLine.obtain(); tl.set(mPaint, mText, start, end, dir, directions, hasTab, tabStops, getEllipsisStart(line), getEllipsisStart(line) + getEllipsisCount(line), isFallbackLineSpacingEnabled()); float wid = tl.measure(offset - start, trailing, null); TextLine.recycle(tl); if (clamped && wid > mWidth) { wid = mWidth; } int left = getParagraphLeft(line); int right = getParagraphRight(line); return getLineStartPos(line, left, right) + wid; } /** * Computes in linear time the results of calling #getHorizontal for all offsets on a line. * * @param line The line giving the offsets we compute information for * @param clamped Whether to clamp the results to the width of the layout * @param primary Whether the results should be the primary or the secondary horizontal * @return The array of results, indexed from 0, where 0 corresponds to the line start offset */ private float[] getLineHorizontals(int line, boolean clamped, boolean primary) { int start = getLineStart(line); int end = getLineEnd(line); int dir = getParagraphDirection(line); boolean hasTab = getLineContainsTab(line); Directions directions = getLineDirections(line); TabStops tabStops = null; if (hasTab && mText instanceof Spanned) { // Just checking this line should be good enough, tabs should be // consistent across all lines in a paragraph. TabStopSpan[] tabs = getParagraphSpans((Spanned) mText, start, end, TabStopSpan.class); if (tabs.length > 0) { tabStops = new TabStops(TAB_INCREMENT, tabs); // XXX should reuse } } TextLine tl = TextLine.obtain(); tl.set(mPaint, mText, start, end, dir, directions, hasTab, tabStops, getEllipsisStart(line), getEllipsisStart(line) + getEllipsisCount(line), isFallbackLineSpacingEnabled()); boolean[] trailings = primaryIsTrailingPreviousAllLineOffsets(line); if (!primary) { for (int offset = 0; offset < trailings.length; ++offset) { trailings[offset] = !trailings[offset]; } } float[] wid = tl.measureAllOffsets(trailings, null); TextLine.recycle(tl); if (clamped) { for (int offset = 0; offset < wid.length; ++offset) { if (wid[offset] > mWidth) { wid[offset] = mWidth; } } } int left = getParagraphLeft(line); int right = getParagraphRight(line); int lineStartPos = getLineStartPos(line, left, right); float[] horizontal = new float[end - start + 1]; for (int offset = 0; offset < horizontal.length; ++offset) { horizontal[offset] = lineStartPos + wid[offset]; } return horizontal; } private void fillHorizontalBoundsForLine(int line, float[] horizontalBounds) { final int lineStart = getLineStart(line); final int lineEnd = getLineEnd(line); final int lineLength = lineEnd - lineStart; final int dir = getParagraphDirection(line); final Directions directions = getLineDirections(line); final boolean hasTab = getLineContainsTab(line); TabStops tabStops = null; if (hasTab && mText instanceof Spanned) { // Just checking this line should be good enough, tabs should be // consistent across all lines in a paragraph. TabStopSpan[] tabs = getParagraphSpans((Spanned) mText, lineStart, lineEnd, TabStopSpan.class); if (tabs.length > 0) { tabStops = new TabStops(TAB_INCREMENT, tabs); // XXX should reuse } } final TextLine tl = TextLine.obtain(); tl.set(mPaint, mText, lineStart, lineEnd, dir, directions, hasTab, tabStops, getEllipsisStart(line), getEllipsisStart(line) + getEllipsisCount(line), isFallbackLineSpacingEnabled()); if (horizontalBounds == null || horizontalBounds.length < 2 * lineLength) { horizontalBounds = new float[2 * lineLength]; } tl.measureAllBounds(horizontalBounds, null); TextLine.recycle(tl); } /** * Return the characters' bounds in the given range. The {@code bounds} array will be filled * starting from {@code boundsStart} (inclusive). The coordinates are in local text layout. * * @param start the start index to compute the character bounds, inclusive. * @param end the end index to compute the character bounds, exclusive. * @param bounds the array to fill in the character bounds. The array is divided into segments * of four where each index in that segment represents left, top, right and * bottom of the character. * @param boundsStart the inclusive start index in the array to start filling in the values * from. * * @throws IndexOutOfBoundsException if the range defined by {@code start} and {@code end} * exceeds the range of the text, or {@code bounds} doesn't have enough space to store the * result. * @throws IllegalArgumentException if {@code bounds} is null. */ public void fillCharacterBounds(@IntRange(from = 0) int start, @IntRange(from = 0) int end, @NonNull float[] bounds, @IntRange(from = 0) int boundsStart) { if (start < 0 || end < start || end > mText.length()) { throw new IndexOutOfBoundsException("given range: " + start + ", " + end + " is " + "out of the text range: 0, " + mText.length()); } if (bounds == null) { throw new IllegalArgumentException("bounds can't be null."); } final int neededLength = 4 * (end - start); if (neededLength > bounds.length - boundsStart) { throw new IndexOutOfBoundsException("bounds doesn't have enough space to store the " + "result, needed: " + neededLength + " had: " + (bounds.length - boundsStart)); } if (start == end) { return; } final int startLine = getLineForOffset(start); final int endLine = getLineForOffset(end - 1); float[] horizontalBounds = null; for (int line = startLine; line <= endLine; ++line) { final int lineStart = getLineStart(line); final int lineEnd = getLineEnd(line); final int lineLength = lineEnd - lineStart; if (horizontalBounds == null || horizontalBounds.length < 2 * lineLength) { horizontalBounds = new float[2 * lineLength]; } fillHorizontalBoundsForLine(line, horizontalBounds); final int lineLeft = getParagraphLeft(line); final int lineRight = getParagraphRight(line); final int lineStartPos = getLineStartPos(line, lineLeft, lineRight); final int lineTop = getLineTop(line); final int lineBottom = getLineBottom(line); final int startIndex = Math.max(start, lineStart); final int endIndex = Math.min(end, lineEnd); for (int index = startIndex; index < endIndex; ++index) { final int offset = index - lineStart; final float left = horizontalBounds[offset * 2] + lineStartPos; final float right = horizontalBounds[offset * 2 + 1] + lineStartPos; final int boundsIndex = boundsStart + 4 * (index - start); bounds[boundsIndex] = left; bounds[boundsIndex + 1] = lineTop; bounds[boundsIndex + 2] = right; bounds[boundsIndex + 3] = lineBottom; } } } /** * Get the leftmost position that should be exposed for horizontal * scrolling on the specified line. */ public float getLineLeft(int line) { final int dir = getParagraphDirection(line); Alignment align = getParagraphAlignment(line); // Before Q, StaticLayout.Builder.setAlignment didn't check whether the input alignment // is null. And when it is null, the old behavior is the same as ALIGN_CENTER. // To keep consistency, we convert a null alignment to ALIGN_CENTER. if (align == null) { align = Alignment.ALIGN_CENTER; } // First convert combinations of alignment and direction settings to // three basic cases: ALIGN_LEFT, ALIGN_RIGHT and ALIGN_CENTER. // For unexpected cases, it will fallback to ALIGN_LEFT. final Alignment resultAlign; switch(align) { case ALIGN_NORMAL: resultAlign = dir == DIR_RIGHT_TO_LEFT ? Alignment.ALIGN_RIGHT : Alignment.ALIGN_LEFT; break; case ALIGN_OPPOSITE: resultAlign = dir == DIR_RIGHT_TO_LEFT ? Alignment.ALIGN_LEFT : Alignment.ALIGN_RIGHT; break; case ALIGN_CENTER: resultAlign = Alignment.ALIGN_CENTER; break; case ALIGN_RIGHT: resultAlign = Alignment.ALIGN_RIGHT; break; default: /* align == Alignment.ALIGN_LEFT */ resultAlign = Alignment.ALIGN_LEFT; } // Here we must use getLineMax() to do the computation, because it maybe overridden by // derived class. And also note that line max equals the width of the text in that line // plus the leading margin. switch (resultAlign) { case ALIGN_CENTER: final int left = getParagraphLeft(line); final float max = getLineMax(line); // This computation only works when mWidth equals leadingMargin plus // the width of text in this line. If this condition doesn't meet anymore, // please change here too. return (float) Math.floor(left + (mWidth - max) / 2); case ALIGN_RIGHT: return mWidth - getLineMax(line); default: /* resultAlign == Alignment.ALIGN_LEFT */ return 0; } } /** * Get the rightmost position that should be exposed for horizontal * scrolling on the specified line. */ public float getLineRight(int line) { final int dir = getParagraphDirection(line); Alignment align = getParagraphAlignment(line); // Before Q, StaticLayout.Builder.setAlignment didn't check whether the input alignment // is null. And when it is null, the old behavior is the same as ALIGN_CENTER. // To keep consistency, we convert a null alignment to ALIGN_CENTER. if (align == null) { align = Alignment.ALIGN_CENTER; } final Alignment resultAlign; switch(align) { case ALIGN_NORMAL: resultAlign = dir == DIR_RIGHT_TO_LEFT ? Alignment.ALIGN_RIGHT : Alignment.ALIGN_LEFT; break; case ALIGN_OPPOSITE: resultAlign = dir == DIR_RIGHT_TO_LEFT ? Alignment.ALIGN_LEFT : Alignment.ALIGN_RIGHT; break; case ALIGN_CENTER: resultAlign = Alignment.ALIGN_CENTER; break; case ALIGN_RIGHT: resultAlign = Alignment.ALIGN_RIGHT; break; default: /* align == Alignment.ALIGN_LEFT */ resultAlign = Alignment.ALIGN_LEFT; } switch (resultAlign) { case ALIGN_CENTER: final int right = getParagraphRight(line); final float max = getLineMax(line); // This computation only works when mWidth equals leadingMargin plus width of the // text in this line. If this condition doesn't meet anymore, please change here. return (float) Math.ceil(right - (mWidth - max) / 2); case ALIGN_RIGHT: return mWidth; default: /* resultAlign == Alignment.ALIGN_LEFT */ return getLineMax(line); } } /** * Gets the unsigned horizontal extent of the specified line, including * leading margin indent, but excluding trailing whitespace. */ public float getLineMax(int line) { float margin = getParagraphLeadingMargin(line); float signedExtent = getLineExtent(line, false); return margin + (signedExtent >= 0 ? signedExtent : -signedExtent); } /** * Gets the unsigned horizontal extent of the specified line, including * leading margin indent and trailing whitespace. */ public float getLineWidth(int line) { float margin = getParagraphLeadingMargin(line); float signedExtent = getLineExtent(line, true); return margin + (signedExtent >= 0 ? signedExtent : -signedExtent); } /** * Like {@link #getLineExtent(int,TabStops,boolean)} but determines the * tab stops instead of using the ones passed in. * @param line the index of the line * @param full whether to include trailing whitespace * @return the extent of the line */ private float getLineExtent(int line, boolean full) { final int start = getLineStart(line); final int end = full ? getLineEnd(line) : getLineVisibleEnd(line); final boolean hasTabs = getLineContainsTab(line); TabStops tabStops = null; if (hasTabs && mText instanceof Spanned) { // Just checking this line should be good enough, tabs should be // consistent across all lines in a paragraph. TabStopSpan[] tabs = getParagraphSpans((Spanned) mText, start, end, TabStopSpan.class); if (tabs.length > 0) { tabStops = new TabStops(TAB_INCREMENT, tabs); // XXX should reuse } } final Directions directions = getLineDirections(line); // Returned directions can actually be null if (directions == null) { return 0f; } final int dir = getParagraphDirection(line); final TextLine tl = TextLine.obtain(); final TextPaint paint = mWorkPaint; paint.set(mPaint); paint.setStartHyphenEdit(getStartHyphenEdit(line)); paint.setEndHyphenEdit(getEndHyphenEdit(line)); tl.set(paint, mText, start, end, dir, directions, hasTabs, tabStops, getEllipsisStart(line), getEllipsisStart(line) + getEllipsisCount(line), isFallbackLineSpacingEnabled()); if (isJustificationRequired(line)) { tl.justify(getJustifyWidth(line)); } final float width = tl.metrics(null); TextLine.recycle(tl); return width; } /** * Returns the signed horizontal extent of the specified line, excluding * leading margin. If full is false, excludes trailing whitespace. * @param line the index of the line * @param tabStops the tab stops, can be null if we know they're not used. * @param full whether to include trailing whitespace * @return the extent of the text on this line */ private float getLineExtent(int line, TabStops tabStops, boolean full) { final int start = getLineStart(line); final int end = full ? getLineEnd(line) : getLineVisibleEnd(line); final boolean hasTabs = getLineContainsTab(line); final Directions directions = getLineDirections(line); final int dir = getParagraphDirection(line); final TextLine tl = TextLine.obtain(); final TextPaint paint = mWorkPaint; paint.set(mPaint); paint.setStartHyphenEdit(getStartHyphenEdit(line)); paint.setEndHyphenEdit(getEndHyphenEdit(line)); tl.set(paint, mText, start, end, dir, directions, hasTabs, tabStops, getEllipsisStart(line), getEllipsisStart(line) + getEllipsisCount(line), isFallbackLineSpacingEnabled()); if (isJustificationRequired(line)) { tl.justify(getJustifyWidth(line)); } final float width = tl.metrics(null); TextLine.recycle(tl); return width; } /** * Get the line number corresponding to the specified vertical position. * If you ask for a position above 0, you get 0; if you ask for a position * below the bottom of the text, you get the last line. */ // FIXME: It may be faster to do a linear search for layouts without many lines. public int getLineForVertical(int vertical) { int high = getLineCount(), low = -1, guess; while (high - low > 1) { guess = (high + low) / 2; if (getLineTop(guess) > vertical) high = guess; else low = guess; } if (low < 0) return 0; else return low; } /** * Get the line number on which the specified text offset appears. * If you ask for a position before 0, you get 0; if you ask for a position * beyond the end of the text, you get the last line. */ public int getLineForOffset(int offset) { int high = getLineCount(), low = -1, guess; while (high - low > 1) { guess = (high + low) / 2; if (getLineStart(guess) > offset) high = guess; else low = guess; } if (low < 0) { return 0; } else { return low; } } /** * Get the character offset on the specified line whose position is * closest to the specified horizontal position. */ public int getOffsetForHorizontal(int line, float horiz) { return getOffsetForHorizontal(line, horiz, true); } /** * Get the character offset on the specified line whose position is * closest to the specified horizontal position. * * @param line the line used to find the closest offset * @param horiz the horizontal position used to find the closest offset * @param primary whether to use the primary position or secondary position to find the offset * * @hide */ public int getOffsetForHorizontal(int line, float horiz, boolean primary) { // TODO: use Paint.getOffsetForAdvance to avoid binary search final int lineEndOffset = getLineEnd(line); final int lineStartOffset = getLineStart(line); Directions dirs = getLineDirections(line); TextLine tl = TextLine.obtain(); // XXX: we don't care about tabs as we just use TextLine#getOffsetToLeftRightOf here. tl.set(mPaint, mText, lineStartOffset, lineEndOffset, getParagraphDirection(line), dirs, false, null, getEllipsisStart(line), getEllipsisStart(line) + getEllipsisCount(line), isFallbackLineSpacingEnabled()); final HorizontalMeasurementProvider horizontal = new HorizontalMeasurementProvider(line, primary); final int max; if (line == getLineCount() - 1) { max = lineEndOffset; } else { max = tl.getOffsetToLeftRightOf(lineEndOffset - lineStartOffset, !isRtlCharAt(lineEndOffset - 1)) + lineStartOffset; } int best = lineStartOffset; float bestdist = Math.abs(horizontal.get(lineStartOffset) - horiz); for (int i = 0; i < dirs.mDirections.length; i += 2) { int here = lineStartOffset + dirs.mDirections[i]; int there = here + (dirs.mDirections[i+1] & RUN_LENGTH_MASK); boolean isRtl = (dirs.mDirections[i+1] & RUN_RTL_FLAG) != 0; int swap = isRtl ? -1 : 1; if (there > max) there = max; int high = there - 1 + 1, low = here + 1 - 1, guess; while (high - low > 1) { guess = (high + low) / 2; int adguess = getOffsetAtStartOf(guess); if (horizontal.get(adguess) * swap >= horiz * swap) { high = guess; } else { low = guess; } } if (low < here + 1) low = here + 1; if (low < there) { int aft = tl.getOffsetToLeftRightOf(low - lineStartOffset, isRtl) + lineStartOffset; low = tl.getOffsetToLeftRightOf(aft - lineStartOffset, !isRtl) + lineStartOffset; if (low >= here && low < there) { float dist = Math.abs(horizontal.get(low) - horiz); if (aft < there) { float other = Math.abs(horizontal.get(aft) - horiz); if (other < dist) { dist = other; low = aft; } } if (dist < bestdist) { bestdist = dist; best = low; } } } float dist = Math.abs(horizontal.get(here) - horiz); if (dist < bestdist) { bestdist = dist; best = here; } } float dist = Math.abs(horizontal.get(max) - horiz); if (dist <= bestdist) { best = max; } TextLine.recycle(tl); return best; } /** * Responds to #getHorizontal queries, by selecting the better strategy between: * - calling #getHorizontal explicitly for each query * - precomputing all #getHorizontal measurements, and responding to any query in constant time * The first strategy is used for LTR-only text, while the second is used for all other cases. * The class is currently only used in #getOffsetForHorizontal, so reuse with care in other * contexts. */ private class HorizontalMeasurementProvider { private final int mLine; private final boolean mPrimary; private float[] mHorizontals; private int mLineStartOffset; HorizontalMeasurementProvider(final int line, final boolean primary) { mLine = line; mPrimary = primary; init(); } private void init() { final Directions dirs = getLineDirections(mLine); if (dirs == DIRS_ALL_LEFT_TO_RIGHT) { return; } mHorizontals = getLineHorizontals(mLine, false, mPrimary); mLineStartOffset = getLineStart(mLine); } float get(final int offset) { final int index = offset - mLineStartOffset; if (mHorizontals == null || index < 0 || index >= mHorizontals.length) { return getHorizontal(offset, mPrimary); } else { return mHorizontals[index]; } } } /** * Finds the range of text which is inside the specified rectangle area. The start of the range * is the start of the first text segment inside the area, and the end of the range is the end * of the last text segment inside the area. * *
A text segment is considered to be inside the area according to the provided {@link * TextInclusionStrategy}. If a text segment spans multiple lines or multiple directional runs * (e.g. a hyphenated word), the text segment is divided into pieces at the line and run breaks, * then the text segment is considered to be inside the area if any of its pieces are inside the * area. * *
The returned range may also include text segments which are not inside the specified area,
* if those text segments are in between text segments which are inside the area. For example,
* the returned range may be "segment1 segment2 segment3" if "segment1" and "segment3" are
* inside the area and "segment2" is not.
*
* @param area area for which the text range will be found
* @param segmentFinder SegmentFinder for determining the ranges of text to be considered as a
* text segment
* @param inclusionStrategy strategy for determining whether a text segment is inside the
* specified area
* @return int array of size 2 containing the start (inclusive) and end (exclusive) character
* offsets of the text range, or null if there are no text segments inside the area
*/
@Nullable
public int[] getRangeForRect(@NonNull RectF area, @NonNull SegmentFinder segmentFinder,
@NonNull TextInclusionStrategy inclusionStrategy) {
// Find the first line whose bottom (without line spacing) is below the top of the area.
int startLine = getLineForVertical((int) area.top);
if (area.top > getLineBottom(startLine, /* includeLineSpacing= */ false)) {
startLine++;
if (startLine >= getLineCount()) {
// The entire area is below the last line, so it does not contain any text.
return null;
}
}
// Find the last line whose top is above the bottom of the area.
int endLine = getLineForVertical((int) area.bottom);
if (endLine == 0 && area.bottom < getLineTop(0)) {
// The entire area is above the first line, so it does not contain any text.
return null;
}
if (endLine < startLine) {
// The entire area is between two lines, so it does not contain any text.
return null;
}
int start = getStartOrEndOffsetForAreaWithinLine(
startLine, area, segmentFinder, inclusionStrategy, /* getStart= */ true);
// If the area does not contain any text on this line, keep trying subsequent lines until
// the end line is reached.
while (start == -1 && startLine < endLine) {
startLine++;
start = getStartOrEndOffsetForAreaWithinLine(
startLine, area, segmentFinder, inclusionStrategy, /* getStart= */ true);
}
if (start == -1) {
// All lines were checked, the area does not contain any text.
return null;
}
int end = getStartOrEndOffsetForAreaWithinLine(
endLine, area, segmentFinder, inclusionStrategy, /* getStart= */ false);
// If the area does not contain any text on this line, keep trying previous lines until
// the start line is reached.
while (end == -1 && startLine < endLine) {
endLine--;
end = getStartOrEndOffsetForAreaWithinLine(
endLine, area, segmentFinder, inclusionStrategy, /* getStart= */ false);
}
if (end == -1) {
// All lines were checked, the area does not contain any text.
return null;
}
// If a text segment spans multiple lines or multiple directional runs (e.g. a hyphenated
// word), then getStartOrEndOffsetForAreaWithinLine() can return an offset in the middle of
// a text segment. Adjust the range to include the rest of any partial text segments. If
// start is already the start boundary of a text segment, then this is a no-op.
start = segmentFinder.previousStartBoundary(start + 1);
end = segmentFinder.nextEndBoundary(end - 1);
return new int[] {start, end};
}
/**
* Finds the start character offset of the first text segment within a line inside the specified
* rectangle area, or the end character offset of the last text segment inside the area.
*
* @param line index of the line to search
* @param area area inside which text segments will be found
* @param segmentFinder SegmentFinder for determining the ranges of text to be considered as a
* text segment
* @param inclusionStrategy strategy for determining whether a text segment is inside the
* specified area
* @param getStart true to find the start of the first text segment inside the area, false to
* find the end of the last text segment
* @return the start character offset of the first text segment inside the area, or the end
* character offset of the last text segment inside the area.
*/
private int getStartOrEndOffsetForAreaWithinLine(
@IntRange(from = 0) int line,
@NonNull RectF area,
@NonNull SegmentFinder segmentFinder,
@NonNull TextInclusionStrategy inclusionStrategy,
boolean getStart) {
int lineTop = getLineTop(line);
int lineBottom = getLineBottom(line, /* includeLineSpacing= */ false);
int lineStartOffset = getLineStart(line);
int lineEndOffset = getLineEnd(line);
if (lineStartOffset == lineEndOffset) {
return -1;
}
float[] horizontalBounds = new float[2 * (lineEndOffset - lineStartOffset)];
fillHorizontalBoundsForLine(line, horizontalBounds);
int lineStartPos = getLineStartPos(line, getParagraphLeft(line), getParagraphRight(line));
// Loop through the runs forwards or backwards depending on getStart value.
Layout.Directions directions = getLineDirections(line);
int runIndex = getStart ? 0 : directions.getRunCount() - 1;
while ((getStart && runIndex < directions.getRunCount()) || (!getStart && runIndex >= 0)) {
// runStartOffset and runEndOffset are offset indices within the line.
int runStartOffset = directions.getRunStart(runIndex);
int runEndOffset = Math.min(
runStartOffset + directions.getRunLength(runIndex),
lineEndOffset - lineStartOffset);
boolean isRtl = directions.isRunRtl(runIndex);
float runLeft = lineStartPos
+ (isRtl
? horizontalBounds[2 * (runEndOffset - 1)]
: horizontalBounds[2 * runStartOffset]);
float runRight = lineStartPos
+ (isRtl
? horizontalBounds[2 * runStartOffset + 1]
: horizontalBounds[2 * (runEndOffset - 1) + 1]);
int result =
getStart
? getStartOffsetForAreaWithinRun(
area, lineTop, lineBottom,
lineStartOffset, lineStartPos, horizontalBounds,
runStartOffset, runEndOffset, runLeft, runRight, isRtl,
segmentFinder, inclusionStrategy)
: getEndOffsetForAreaWithinRun(
area, lineTop, lineBottom,
lineStartOffset, lineStartPos, horizontalBounds,
runStartOffset, runEndOffset, runLeft, runRight, isRtl,
segmentFinder, inclusionStrategy);
if (result >= 0) {
return result;
}
runIndex += getStart ? 1 : -1;
}
return -1;
}
/**
* Finds the start character offset of the first text segment within a directional run inside
* the specified rectangle area.
*
* @param area area inside which text segments will be found
* @param lineTop top of the line containing this run
* @param lineBottom bottom (not including line spacing) of the line containing this run
* @param lineStartOffset start character offset of the line containing this run
* @param lineStartPos start position of the line containing this run
* @param horizontalBounds array containing the signed horizontal bounds of the characters in
* the line. The left and right bounds of the character at offset i are stored at index (2 *
* i) and index (2 * i + 1). Bounds are relative to {@code lineStartPos}.
* @param runStartOffset start offset of the run relative to {@code lineStartOffset}
* @param runEndOffset end offset of the run relative to {@code lineStartOffset}
* @param runLeft left bound of the run
* @param runRight right bound of the run
* @param isRtl whether the run is right-to-left
* @param segmentFinder SegmentFinder for determining the ranges of text to be considered as a
* text segment
* @param inclusionStrategy strategy for determining whether a text segment is inside the
* specified area
* @return the start character offset of the first text segment inside the area
*/
private static int getStartOffsetForAreaWithinRun(
@NonNull RectF area,
int lineTop, int lineBottom,
@IntRange(from = 0) int lineStartOffset,
@IntRange(from = 0) int lineStartPos,
@NonNull float[] horizontalBounds,
@IntRange(from = 0) int runStartOffset, @IntRange(from = 0) int runEndOffset,
float runLeft, float runRight,
boolean isRtl,
@NonNull SegmentFinder segmentFinder,
@NonNull TextInclusionStrategy inclusionStrategy) {
if (runRight < area.left || runLeft > area.right) {
// The run does not overlap the area.
return -1;
}
// Find the first character in the run whose bounds overlap with the area.
// firstCharOffset is an offset index within the line.
int firstCharOffset;
if ((!isRtl && area.left <= runLeft) || (isRtl && area.right >= runRight)) {
firstCharOffset = runStartOffset;
} else {
int low = runStartOffset;
int high = runEndOffset;
int guess;
while (high - low > 1) {
guess = (high + low) / 2;
// Left edge of the character at guess
float pos = lineStartPos + horizontalBounds[2 * guess];
if ((!isRtl && pos > area.left) || (isRtl && pos < area.right)) {
high = guess;
} else {
low = guess;
}
}
// The area edge is between the left edge of the character at low and the left edge of
// the character at high. For LTR text, this is within the character at low. For RTL
// text, this is within the character at high.
firstCharOffset = isRtl ? high : low;
}
// Find the first text segment containing this character (or, if no text segment contains
// this character, the first text segment after this character). All previous text segments
// in this run are to the left (for LTR) of the area.
int segmentEndOffset =
segmentFinder.nextEndBoundary(lineStartOffset + firstCharOffset);
if (segmentEndOffset == SegmentFinder.DONE) {
// There are no text segments containing or after firstCharOffset, so no text segments
// in this run overlap the area.
return -1;
}
int segmentStartOffset = segmentFinder.previousStartBoundary(segmentEndOffset);
if (segmentStartOffset >= lineStartOffset + runEndOffset) {
// The text segment is after the end of this run, so no text segments in this run
// overlap the area.
return -1;
}
// If the segment extends outside of this run, only consider the piece of the segment within
// this run.
segmentStartOffset = Math.max(segmentStartOffset, lineStartOffset + runStartOffset);
segmentEndOffset = Math.min(segmentEndOffset, lineStartOffset + runEndOffset);
RectF segmentBounds = new RectF(0, lineTop, 0, lineBottom);
while (true) {
// Start (left for LTR, right for RTL) edge of the character at segmentStartOffset.
float segmentStart = lineStartPos + horizontalBounds[
2 * (segmentStartOffset - lineStartOffset) + (isRtl ? 1 : 0)];
if ((!isRtl && segmentStart > area.right) || (isRtl && segmentStart < area.left)) {
// The entire area is to the left (for LTR) of the text segment. So the area does
// not contain any text segments within this run.
return -1;
}
// End (right for LTR, left for RTL) edge of the character at (segmentStartOffset - 1).
float segmentEnd = lineStartPos + horizontalBounds[
2 * (segmentEndOffset - lineStartOffset - 1) + (isRtl ? 0 : 1)];
segmentBounds.left = isRtl ? segmentEnd : segmentStart;
segmentBounds.right = isRtl ? segmentStart : segmentEnd;
if (inclusionStrategy.isSegmentInside(segmentBounds, area)) {
return segmentStartOffset;
}
// Try the next text segment.
segmentStartOffset = segmentFinder.nextStartBoundary(segmentStartOffset);
if (segmentStartOffset == SegmentFinder.DONE
|| segmentStartOffset >= lineStartOffset + runEndOffset) {
// No more text segments within this run.
return -1;
}
segmentEndOffset = segmentFinder.nextEndBoundary(segmentStartOffset);
// If the segment extends past the end of this run, only consider the piece of the
// segment within this run.
segmentEndOffset = Math.min(segmentEndOffset, lineStartOffset + runEndOffset);
}
}
/**
* Finds the end character offset of the last text segment within a directional run inside the
* specified rectangle area.
*
* @param area area inside which text segments will be found
* @param lineTop top of the line containing this run
* @param lineBottom bottom (not including line spacing) of the line containing this run
* @param lineStartOffset start character offset of the line containing this run
* @param lineStartPos start position of the line containing this run
* @param horizontalBounds array containing the signed horizontal bounds of the characters in
* the line. The left and right bounds of the character at offset i are stored at index (2 *
* i) and index (2 * i + 1). Bounds are relative to {@code lineStartPos}.
* @param runStartOffset start offset of the run relative to {@code lineStartOffset}
* @param runEndOffset end offset of the run relative to {@code lineStartOffset}
* @param runLeft left bound of the run
* @param runRight right bound of the run
* @param isRtl whether the run is right-to-left
* @param segmentFinder SegmentFinder for determining the ranges of text to be considered as a
* text segment
* @param inclusionStrategy strategy for determining whether a text segment is inside the
* specified area
* @return the end character offset of the last text segment inside the area
*/
private static int getEndOffsetForAreaWithinRun(
@NonNull RectF area,
int lineTop, int lineBottom,
@IntRange(from = 0) int lineStartOffset,
@IntRange(from = 0) int lineStartPos,
@NonNull float[] horizontalBounds,
@IntRange(from = 0) int runStartOffset, @IntRange(from = 0) int runEndOffset,
float runLeft, float runRight,
boolean isRtl,
@NonNull SegmentFinder segmentFinder,
@NonNull TextInclusionStrategy inclusionStrategy) {
if (runRight < area.left || runLeft > area.right) {
// The run does not overlap the area.
return -1;
}
// Find the last character in the run whose bounds overlap with the area.
// firstCharOffset is an offset index within the line.
int lastCharOffset;
if ((!isRtl && area.right >= runRight) || (isRtl && area.left <= runLeft)) {
lastCharOffset = runEndOffset - 1;
} else {
int low = runStartOffset;
int high = runEndOffset;
int guess;
while (high - low > 1) {
guess = (high + low) / 2;
// Left edge of the character at guess
float pos = lineStartPos + horizontalBounds[2 * guess];
if ((!isRtl && pos > area.right) || (isRtl && pos < area.left)) {
high = guess;
} else {
low = guess;
}
}
// The area edge is between the left edge of the character at low and the left edge of
// the character at high. For LTR text, this is within the character at low. For RTL
// text, this is within the character at high.
lastCharOffset = isRtl ? high : low;
}
// Find the last text segment containing this character (or, if no text segment contains
// this character, the first text segment before this character). All following text
// segments in this run are to the right (for LTR) of the area.
// + 1 to allow segmentStartOffset = lineStartOffset + lastCharOffset
int segmentStartOffset =
segmentFinder.previousStartBoundary(lineStartOffset + lastCharOffset + 1);
if (segmentStartOffset == SegmentFinder.DONE) {
// There are no text segments containing or before lastCharOffset, so no text segments
// in this run overlap the area.
return -1;
}
int segmentEndOffset = segmentFinder.nextEndBoundary(segmentStartOffset);
if (segmentEndOffset <= lineStartOffset + runStartOffset) {
// The text segment is before the start of this run, so no text segments in this run
// overlap the area.
return -1;
}
// If the segment extends outside of this run, only consider the piece of the segment within
// this run.
segmentStartOffset = Math.max(segmentStartOffset, lineStartOffset + runStartOffset);
segmentEndOffset = Math.min(segmentEndOffset, lineStartOffset + runEndOffset);
RectF segmentBounds = new RectF(0, lineTop, 0, lineBottom);
while (true) {
// End (right for LTR, left for RTL) edge of the character at (segmentStartOffset - 1).
float segmentEnd = lineStartPos + horizontalBounds[
2 * (segmentEndOffset - lineStartOffset - 1) + (isRtl ? 0 : 1)];
if ((!isRtl && segmentEnd < area.left) || (isRtl && segmentEnd > area.right)) {
// The entire area is to the right (for LTR) of the text segment. So the
// area does not contain any text segments within this run.
return -1;
}
// Start (left for LTR, right for RTL) edge of the character at segmentStartOffset.
float segmentStart = lineStartPos + horizontalBounds[
2 * (segmentStartOffset - lineStartOffset) + (isRtl ? 1 : 0)];
segmentBounds.left = isRtl ? segmentEnd : segmentStart;
segmentBounds.right = isRtl ? segmentStart : segmentEnd;
if (inclusionStrategy.isSegmentInside(segmentBounds, area)) {
return segmentEndOffset;
}
// Try the previous text segment.
segmentEndOffset = segmentFinder.previousEndBoundary(segmentEndOffset);
if (segmentEndOffset == SegmentFinder.DONE
|| segmentEndOffset <= lineStartOffset + runStartOffset) {
// No more text segments within this run.
return -1;
}
segmentStartOffset = segmentFinder.previousStartBoundary(segmentEndOffset);
// If the segment extends past the start of this run, only consider the piece of the
// segment within this run.
segmentStartOffset = Math.max(segmentStartOffset, lineStartOffset + runStartOffset);
}
}
/**
* Return the text offset after the last character on the specified line.
*/
public final int getLineEnd(int line) {
return getLineStart(line + 1);
}
/**
* Return the text offset after the last visible character (so whitespace
* is not counted) on the specified line.
*/
public int getLineVisibleEnd(int line) {
return getLineVisibleEnd(line, getLineStart(line), getLineStart(line+1));
}
private int getLineVisibleEnd(int line, int start, int end) {
CharSequence text = mText;
char ch;
if (line == getLineCount() - 1) {
return end;
}
for (; end > start; end--) {
ch = text.charAt(end - 1);
if (ch == '\n') {
return end - 1;
}
if (!TextLine.isLineEndSpace(ch)) {
break;
}
}
return end;
}
/**
* Return the vertical position of the bottom of the specified line.
*/
public final int getLineBottom(int line) {
return getLineBottom(line, /* includeLineSpacing= */ true);
}
/**
* Return the vertical position of the bottom of the specified line.
*
* @param line index of the line
* @param includeLineSpacing whether to include the line spacing
*/
public int getLineBottom(int line, boolean includeLineSpacing) {
if (includeLineSpacing) {
return getLineTop(line + 1);
} else {
return getLineTop(line + 1) - getLineExtra(line);
}
}
/**
* Return the vertical position of the baseline of the specified line.
*/
public final int getLineBaseline(int line) {
// getLineTop(line+1) == getLineBottom(line)
return getLineTop(line+1) - getLineDescent(line);
}
/**
* Get the ascent of the text on the specified line.
* The return value is negative to match the Paint.ascent() convention.
*/
public final int getLineAscent(int line) {
// getLineTop(line+1) - getLineDescent(line) == getLineBaseLine(line)
return getLineTop(line) - (getLineTop(line+1) - getLineDescent(line));
}
/**
* Return the extra space added as a result of line spacing attributes
* {@link #getSpacingAdd()} and {@link #getSpacingMultiplier()}. Default value is {@code zero}.
*
* @param line the index of the line, the value should be equal or greater than {@code zero}
* @hide
*/
public int getLineExtra(@IntRange(from = 0) int line) {
return 0;
}
public int getOffsetToLeftOf(int offset) {
return getOffsetToLeftRightOf(offset, true);
}
public int getOffsetToRightOf(int offset) {
return getOffsetToLeftRightOf(offset, false);
}
private int getOffsetToLeftRightOf(int caret, boolean toLeft) {
int line = getLineForOffset(caret);
int lineStart = getLineStart(line);
int lineEnd = getLineEnd(line);
int lineDir = getParagraphDirection(line);
boolean lineChanged = false;
boolean advance = toLeft == (lineDir == DIR_RIGHT_TO_LEFT);
// if walking off line, look at the line we're headed to
if (advance) {
if (caret == lineEnd) {
if (line < getLineCount() - 1) {
lineChanged = true;
++line;
} else {
return caret; // at very end, don't move
}
}
} else {
if (caret == lineStart) {
if (line > 0) {
lineChanged = true;
--line;
} else {
return caret; // at very start, don't move
}
}
}
if (lineChanged) {
lineStart = getLineStart(line);
lineEnd = getLineEnd(line);
int newDir = getParagraphDirection(line);
if (newDir != lineDir) {
// unusual case. we want to walk onto the line, but it runs
// in a different direction than this one, so we fake movement
// in the opposite direction.
toLeft = !toLeft;
lineDir = newDir;
}
}
Directions directions = getLineDirections(line);
TextLine tl = TextLine.obtain();
// XXX: we don't care about tabs
tl.set(mPaint, mText, lineStart, lineEnd, lineDir, directions, false, null,
getEllipsisStart(line), getEllipsisStart(line) + getEllipsisCount(line),
isFallbackLineSpacingEnabled());
caret = lineStart + tl.getOffsetToLeftRightOf(caret - lineStart, toLeft);
TextLine.recycle(tl);
return caret;
}
private int getOffsetAtStartOf(int offset) {
// XXX this probably should skip local reorderings and
// zero-width characters, look at callers
if (offset == 0)
return 0;
CharSequence text = mText;
char c = text.charAt(offset);
if (c >= '\uDC00' && c <= '\uDFFF') {
char c1 = text.charAt(offset - 1);
if (c1 >= '\uD800' && c1 <= '\uDBFF')
offset -= 1;
}
if (mSpannedText) {
ReplacementSpan[] spans = ((Spanned) text).getSpans(offset, offset,
ReplacementSpan.class);
for (int i = 0; i < spans.length; i++) {
int start = ((Spanned) text).getSpanStart(spans[i]);
int end = ((Spanned) text).getSpanEnd(spans[i]);
if (start < offset && end > offset)
offset = start;
}
}
return offset;
}
/**
* Determine whether we should clamp cursor position. Currently it's
* only robust for left-aligned displays.
* @hide
*/
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
public boolean shouldClampCursor(int line) {
// Only clamp cursor position in left-aligned displays.
switch (getParagraphAlignment(line)) {
case ALIGN_LEFT:
return true;
case ALIGN_NORMAL:
return getParagraphDirection(line) > 0;
default:
return false;
}
}
/**
* Fills in the specified Path with a representation of a cursor
* at the specified offset. This will often be a vertical line
* but can be multiple discontinuous lines in text with multiple
* directionalities.
*/
public void getCursorPath(final int point, final Path dest, final CharSequence editingBuffer) {
dest.reset();
int line = getLineForOffset(point);
int top = getLineTop(line);
int bottom = getLineBottom(line, /* includeLineSpacing= */ false);
boolean clamped = shouldClampCursor(line);
float h1 = getPrimaryHorizontal(point, clamped) - 0.5f;
int caps = TextKeyListener.getMetaState(editingBuffer, TextKeyListener.META_SHIFT_ON) |
TextKeyListener.getMetaState(editingBuffer, TextKeyListener.META_SELECTING);
int fn = TextKeyListener.getMetaState(editingBuffer, TextKeyListener.META_ALT_ON);
int dist = 0;
if (caps != 0 || fn != 0) {
dist = (bottom - top) >> 2;
if (fn != 0)
top += dist;
if (caps != 0)
bottom -= dist;
}
if (h1 < 0.5f)
h1 = 0.5f;
dest.moveTo(h1, top);
dest.lineTo(h1, bottom);
if (caps == 2) {
dest.moveTo(h1, bottom);
dest.lineTo(h1 - dist, bottom + dist);
dest.lineTo(h1, bottom);
dest.lineTo(h1 + dist, bottom + dist);
} else if (caps == 1) {
dest.moveTo(h1, bottom);
dest.lineTo(h1 - dist, bottom + dist);
dest.moveTo(h1 - dist, bottom + dist - 0.5f);
dest.lineTo(h1 + dist, bottom + dist - 0.5f);
dest.moveTo(h1 + dist, bottom + dist);
dest.lineTo(h1, bottom);
}
if (fn == 2) {
dest.moveTo(h1, top);
dest.lineTo(h1 - dist, top - dist);
dest.lineTo(h1, top);
dest.lineTo(h1 + dist, top - dist);
} else if (fn == 1) {
dest.moveTo(h1, top);
dest.lineTo(h1 - dist, top - dist);
dest.moveTo(h1 - dist, top - dist + 0.5f);
dest.lineTo(h1 + dist, top - dist + 0.5f);
dest.moveTo(h1 + dist, top - dist);
dest.lineTo(h1, top);
}
}
private void addSelection(int line, int start, int end,
int top, int bottom, SelectionRectangleConsumer consumer) {
int linestart = getLineStart(line);
int lineend = getLineEnd(line);
Directions dirs = getLineDirections(line);
if (lineend > linestart && mText.charAt(lineend - 1) == '\n') {
lineend--;
}
for (int i = 0; i < dirs.mDirections.length; i += 2) {
int here = linestart + dirs.mDirections[i];
int there = here + (dirs.mDirections[i + 1] & RUN_LENGTH_MASK);
if (there > lineend) {
there = lineend;
}
if (start <= there && end >= here) {
int st = Math.max(start, here);
int en = Math.min(end, there);
if (st != en) {
float h1 = getHorizontal(st, false, line, false /* not clamped */);
float h2 = getHorizontal(en, true, line, false /* not clamped */);
float left = Math.min(h1, h2);
float right = Math.max(h1, h2);
final @TextSelectionLayout int layout =
((dirs.mDirections[i + 1] & RUN_RTL_FLAG) != 0)
? TEXT_SELECTION_LAYOUT_RIGHT_TO_LEFT
: TEXT_SELECTION_LAYOUT_LEFT_TO_RIGHT;
consumer.accept(left, top, right, bottom, layout);
}
}
}
}
/**
* Fills in the specified Path with a representation of a highlight
* between the specified offsets. This will often be a rectangle
* or a potentially discontinuous set of rectangles. If the start
* and end are the same, the returned path is empty.
*/
public void getSelectionPath(int start, int end, Path dest) {
dest.reset();
getSelection(start, end, (left, top, right, bottom, textSelectionLayout) ->
dest.addRect(left, top, right, bottom, Path.Direction.CW));
}
/**
* Calculates the rectangles which should be highlighted to indicate a selection between start
* and end and feeds them into the given {@link SelectionRectangleConsumer}.
*
* @param start the starting index of the selection
* @param end the ending index of the selection
* @param consumer the {@link SelectionRectangleConsumer} which will receive the generated
* rectangles. It will be called every time a rectangle is generated.
* @hide
* @see #getSelectionPath(int, int, Path)
*/
public final void getSelection(int start, int end, final SelectionRectangleConsumer consumer) {
if (start == end) {
return;
}
if (end < start) {
int temp = end;
end = start;
start = temp;
}
final int startline = getLineForOffset(start);
final int endline = getLineForOffset(end);
int top = getLineTop(startline);
int bottom = getLineBottom(endline, /* includeLineSpacing= */ false);
if (startline == endline) {
addSelection(startline, start, end, top, bottom, consumer);
} else {
final float width = mWidth;
addSelection(startline, start, getLineEnd(startline),
top, getLineBottom(startline), consumer);
if (getParagraphDirection(startline) == DIR_RIGHT_TO_LEFT) {
consumer.accept(getLineLeft(startline), top, 0, getLineBottom(startline),
TEXT_SELECTION_LAYOUT_RIGHT_TO_LEFT);
} else {
consumer.accept(getLineRight(startline), top, width, getLineBottom(startline),
TEXT_SELECTION_LAYOUT_LEFT_TO_RIGHT);
}
for (int i = startline + 1; i < endline; i++) {
top = getLineTop(i);
bottom = getLineBottom(i);
if (getParagraphDirection(i) == DIR_RIGHT_TO_LEFT) {
consumer.accept(0, top, width, bottom, TEXT_SELECTION_LAYOUT_RIGHT_TO_LEFT);
} else {
consumer.accept(0, top, width, bottom, TEXT_SELECTION_LAYOUT_LEFT_TO_RIGHT);
}
}
top = getLineTop(endline);
bottom = getLineBottom(endline, /* includeLineSpacing= */ false);
addSelection(endline, getLineStart(endline), end, top, bottom, consumer);
if (getParagraphDirection(endline) == DIR_RIGHT_TO_LEFT) {
consumer.accept(width, top, getLineRight(endline), bottom,
TEXT_SELECTION_LAYOUT_RIGHT_TO_LEFT);
} else {
consumer.accept(0, top, getLineLeft(endline), bottom,
TEXT_SELECTION_LAYOUT_LEFT_TO_RIGHT);
}
}
}
/**
* Get the alignment of the specified paragraph, taking into account
* markup attached to it.
*/
public final Alignment getParagraphAlignment(int line) {
Alignment align = mAlignment;
if (mSpannedText) {
Spanned sp = (Spanned) mText;
AlignmentSpan[] spans = getParagraphSpans(sp, getLineStart(line),
getLineEnd(line),
AlignmentSpan.class);
int spanLength = spans.length;
if (spanLength > 0) {
align = spans[spanLength-1].getAlignment();
}
}
return align;
}
/**
* Get the left edge of the specified paragraph, inset by left margins.
*/
public final int getParagraphLeft(int line) {
int left = 0;
int dir = getParagraphDirection(line);
if (dir == DIR_RIGHT_TO_LEFT || !mSpannedText) {
return left; // leading margin has no impact, or no styles
}
return getParagraphLeadingMargin(line);
}
/**
* Get the right edge of the specified paragraph, inset by right margins.
*/
public final int getParagraphRight(int line) {
int right = mWidth;
int dir = getParagraphDirection(line);
if (dir == DIR_LEFT_TO_RIGHT || !mSpannedText) {
return right; // leading margin has no impact, or no styles
}
return right - getParagraphLeadingMargin(line);
}
/**
* Returns the effective leading margin (unsigned) for this line,
* taking into account LeadingMarginSpan and LeadingMarginSpan2.
* @param line the line index
* @return the leading margin of this line
*/
private int getParagraphLeadingMargin(int line) {
if (!mSpannedText) {
return 0;
}
Spanned spanned = (Spanned) mText;
int lineStart = getLineStart(line);
int lineEnd = getLineEnd(line);
int spanEnd = spanned.nextSpanTransition(lineStart, lineEnd,
LeadingMarginSpan.class);
LeadingMarginSpan[] spans = getParagraphSpans(spanned, lineStart, spanEnd,
LeadingMarginSpan.class);
if (spans.length == 0) {
return 0; // no leading margin span;
}
int margin = 0;
boolean useFirstLineMargin = lineStart == 0 || spanned.charAt(lineStart - 1) == '\n';
for (int i = 0; i < spans.length; i++) {
if (spans[i] instanceof LeadingMarginSpan2) {
int spStart = spanned.getSpanStart(spans[i]);
int spanLine = getLineForOffset(spStart);
int count = ((LeadingMarginSpan2) spans[i]).getLeadingMarginLineCount();
// if there is more than one LeadingMarginSpan2, use the count that is greatest
useFirstLineMargin |= line < spanLine + count;
}
}
for (int i = 0; i < spans.length; i++) {
LeadingMarginSpan span = spans[i];
margin += span.getLeadingMargin(useFirstLineMargin);
}
return margin;
}
private static float measurePara(TextPaint paint, CharSequence text, int start, int end,
TextDirectionHeuristic textDir) {
MeasuredParagraph mt = null;
TextLine tl = TextLine.obtain();
try {
mt = MeasuredParagraph.buildForBidi(text, start, end, textDir, mt);
final char[] chars = mt.getChars();
final int len = chars.length;
final Directions directions = mt.getDirections(0, len);
final int dir = mt.getParagraphDir();
boolean hasTabs = false;
TabStops tabStops = null;
// leading margins should be taken into account when measuring a paragraph
int margin = 0;
if (text instanceof Spanned) {
Spanned spanned = (Spanned) text;
LeadingMarginSpan[] spans = getParagraphSpans(spanned, start, end,
LeadingMarginSpan.class);
for (LeadingMarginSpan lms : spans) {
margin += lms.getLeadingMargin(true);
}
}
for (int i = 0; i < len; ++i) {
if (chars[i] == '\t') {
hasTabs = true;
if (text instanceof Spanned) {
Spanned spanned = (Spanned) text;
int spanEnd = spanned.nextSpanTransition(start, end,
TabStopSpan.class);
TabStopSpan[] spans = getParagraphSpans(spanned, start, spanEnd,
TabStopSpan.class);
if (spans.length > 0) {
tabStops = new TabStops(TAB_INCREMENT, spans);
}
}
break;
}
}
tl.set(paint, text, start, end, dir, directions, hasTabs, tabStops,
0 /* ellipsisStart */, 0 /* ellipsisEnd */,
false /* use fallback line spacing. unused */);
return margin + Math.abs(tl.metrics(null));
} finally {
TextLine.recycle(tl);
if (mt != null) {
mt.recycle();
}
}
}
/**
* @hide
*/
@VisibleForTesting(visibility = VisibleForTesting.Visibility.PACKAGE)
public static class TabStops {
private float[] mStops;
private int mNumStops;
private float mIncrement;
public TabStops(float increment, Object[] spans) {
reset(increment, spans);
}
void reset(float increment, Object[] spans) {
this.mIncrement = increment;
int ns = 0;
if (spans != null) {
float[] stops = this.mStops;
for (Object o : spans) {
if (o instanceof TabStopSpan) {
if (stops == null) {
stops = new float[10];
} else if (ns == stops.length) {
float[] nstops = new float[ns * 2];
for (int i = 0; i < ns; ++i) {
nstops[i] = stops[i];
}
stops = nstops;
}
stops[ns++] = ((TabStopSpan) o).getTabStop();
}
}
if (ns > 1) {
Arrays.sort(stops, 0, ns);
}
if (stops != this.mStops) {
this.mStops = stops;
}
}
this.mNumStops = ns;
}
float nextTab(float h) {
int ns = this.mNumStops;
if (ns > 0) {
float[] stops = this.mStops;
for (int i = 0; i < ns; ++i) {
float stop = stops[i];
if (stop > h) {
return stop;
}
}
}
return nextDefaultStop(h, mIncrement);
}
/**
* Returns the position of next tab stop.
*/
public static float nextDefaultStop(float h, float inc) {
return ((int) ((h + inc) / inc)) * inc;
}
}
/**
* Returns the position of the next tab stop after h on the line.
*
* @param text the text
* @param start start of the line
* @param end limit of the line
* @param h the current horizontal offset
* @param tabs the tabs, can be null. If it is null, any tabs in effect
* on the line will be used. If there are no tabs, a default offset
* will be used to compute the tab stop.
* @return the offset of the next tab stop.
*/
/* package */ static float nextTab(CharSequence text, int start, int end,
float h, Object[] tabs) {
float nh = Float.MAX_VALUE;
boolean alltabs = false;
if (text instanceof Spanned) {
if (tabs == null) {
tabs = getParagraphSpans((Spanned) text, start, end, TabStopSpan.class);
alltabs = true;
}
for (int i = 0; i < tabs.length; i++) {
if (!alltabs) {
if (!(tabs[i] instanceof TabStopSpan))
continue;
}
int where = ((TabStopSpan) tabs[i]).getTabStop();
if (where < nh && where > h)
nh = where;
}
if (nh != Float.MAX_VALUE)
return nh;
}
return ((int) ((h + TAB_INCREMENT) / TAB_INCREMENT)) * TAB_INCREMENT;
}
protected final boolean isSpanned() {
return mSpannedText;
}
/**
* Returns the same as text.getSpans(), except where
* start and end are the same and are not
* at the very beginning of the text, in which case an empty array
* is returned instead.
*
* This is needed because of the special case that getSpans()
* on an empty range returns the spans adjacent to that range, which is
* primarily for the sake of TextWatchers so they will get
* notifications when text goes from empty to non-empty. But it also
* has the unfortunate side effect that if the text ends with an empty
* paragraph, that paragraph accidentally picks up the styles of the
* preceding paragraph (even though those styles will not be picked up
* by new text that is inserted into the empty paragraph).
*
* The reason it just checks whether The segment is a range of text which does not cross line boundaries or directional run
* boundaries. The horizontal bounds of the segment are the start bound of the first
* character to the end bound of the last character. The vertical bounds match the line
* bounds ({@code getLineTop(line)} and {@code getLineBottom(line, false)}).
*/
boolean isSegmentInside(@NonNull RectF segmentBounds, @NonNull RectF area);
}
}
start and end
* is the same is that the only time a line can contain 0 characters
* is if it is the final paragraph of the Layout; otherwise any line will
* contain at least one printing or newline character. The reason for the
* additional check if start is greater than 0 is that
* if the empty paragraph is the entire content of the buffer, paragraph
* styles that are already applied to the buffer will apply to text that
* is inserted into it.
*/
/* package */static