1 /*
2  * Copyright (C) 2021 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package android.view.translation;
18 
19 import android.annotation.NonNull;
20 import android.annotation.UiThread;
21 import android.view.View;
22 import android.view.contentcapture.ContentCaptureSession;
23 
24 /**
25  * <p> Callback for handling the translated information show or hide in the {@link View}.
26  *
27  * <p> When the platform intelligence starts translation of an app's ui, the system will call
28  * {@link View#dispatchCreateViewTranslationRequest} to collect the {@link ViewTranslationRequest}s
29  * for translation purpose by traversing the hierarchy then send to translation service. After
30  * receiving the {@link ViewTranslationResponse}, the system will call
31  * {@link ViewTranslationCallback#onShowTranslation(View)} to show the translated information for
32  * the {@link View}.
33  */
34 @UiThread
35 public interface ViewTranslationCallback {
36     /**
37      * Called when the translated text is ready to show or if the user has requested to reshow the
38      * translated content after hiding it.
39      * <p>
40      * The translated content can be obtained from {@link View#getViewTranslationResponse}. This
41      * method will not be called before {@link View#onViewTranslationResponse} or
42      * {@link View#onVirtualViewTranslationResponses}.
43      *
44      * <p> NOTE: It is possible the user changes text that causes a new
45      * {@link ViewTranslationResponse} returns to show the new translation. If you cache the
46      * {@link ViewTranslationResponse} here, you should remember to keep the cached value up
47      * to date.
48      *
49      * <p> NOTE: For TextView implementation, {@link ContentCaptureSession#notifyViewTextChanged}
50      * shouldn't be called with the translated text, simply calling setText() here will trigger the
51      * method. You should either override {@code View#onProvideContentCaptureStructure()} to report
52      * the original text instead of the translated text or use a different approach to display the
53      * translated text.
54      *
55      * <p> NOTE: In Android version {@link android.os.Build.VERSION_CODES#TIRAMISU} and later,
56      * the implementation must be able to handle a selectable {@link android.widget.TextView}
57      * (i.e., {@link android.widget.TextView#isTextSelectable()} returns {@code true}. The default
58      * callback implementation for TextView uses a {@link android.text.method.TransformationMethod}
59      * to show the translated text, which will cause a crash when the translated text is selected.
60      * Therefore, the default callback temporarily makes the TextView non-selectable while the
61      * translation text is shown. This is one approach for handling selectable TextViews a
62      * TransformationMethod is used.
63      *
64      * See {@link View#onViewTranslationResponse} for how to get the translated information.
65      *
66      * @return {@code true} if the View handles showing the translation.
67      */
onShowTranslation(@onNull View view)68     boolean onShowTranslation(@NonNull View view);
69     /**
70      * Called when user wants to view the original content instead of the translated content. This
71      * method will not be called before {@link View#onViewTranslationResponse} or
72      * {@link View#onVirtualViewTranslationResponses}.
73      *
74      * @return {@code true} if the View handles hiding the translation.
75      */
onHideTranslation(@onNull View view)76     boolean onHideTranslation(@NonNull View view);
77     /**
78      * Called when the translation state is no longer needed. It should restore the original content
79      * and clear all saved states.
80      *
81      * @return {@code true} if the View handles clearing the translation.
82      */
onClearTranslation(@onNull View view)83     boolean onClearTranslation(@NonNull View view);
84 
85     /**
86      * Enables padding on the view's original content.
87      * <p>
88      * This is useful when we do not modify the content directly, rather use a mechanism like
89      * {@link android.text.method.TransformationMethod}. If the app misbehaves when the displayed
90      * translation and the underlying content have different sizes, the platform intelligence can
91      * request that the original content be padded to make the sizes match.
92      *
93      * @hide
94      */
enableContentPadding()95     default void enableContentPadding() {}
96 
97     /**
98      * Sets the duration for animations while transitioning the view between the original and
99      * translated contents.
100      *
101      * @hide
102      */
setAnimationDurationMillis(int durationMillis)103     default void setAnimationDurationMillis(int durationMillis) {}
104 }
105