[Android Text Input] Make the editing state listenable and allow batch edits

shell/platform/android/io/flutter/plugin/editing/InputConnectionAdaptor.java

@@ -43,8 +43,7 @@ class InputConnectionAdaptor extends BaseInputConnection {
   // Used to determine if Samsung-specific hacks should be applied.
   private final boolean isSamsung;
 
-  private boolean mRepeatCheckNeeded = false;
-  private TextEditingValue mLastSentTextEditngValue;
+  private TextEditingValue mLastKnownTextEditingValue;
   // Data class used to get and store the last-sent values via updateEditingState to
   // the  framework. These are then compared against to prevent redundant messages
   // with the same data before any valid operations were made to the contents.
@@ -144,7 +143,7 @@ private void updateEditingState() {
     // occurred to mark this as dirty. This prevents duplicate remote updates of
     // the same data, which can break formatters that change the length of the
     // contents.
-    if (mRepeatCheckNeeded && currentValue.equals(mLastSentTextEditngValue)) {
+    if (currentValue.equals(mLastKnownTextEditingValue)) {
       return;
     }
 
@@ -163,17 +162,13 @@ private void updateEditingState() {
         currentValue.composingStart,
         currentValue.composingEnd);
 
-    mRepeatCheckNeeded = true;
-    mLastSentTextEditngValue = currentValue;
+    mLastKnownTextEditingValue = currentValue;
   }
 
-  // This should be called whenever a change could have been made to
-  // the value of mEditable, which will make any call of updateEditingState()
-  // ineligible for repeat checking as we do not want to skip sending real changes
-  // to the framework.
-  public void markDirty() {
-    // Disable updateEditngState's repeat-update check
-    mRepeatCheckNeeded = false;
+  // Called when the current text editing state held by the text input plugin is overwritten by a
+  // newly received value from the framework.
+  public void didUpdateEditingValue() {
+    mLastKnownTextEditingValue = new TextEditingValue(mEditable);
   }
 
   @Override
@@ -198,7 +193,6 @@ public boolean endBatchEdit() {
   @Override
   public boolean commitText(CharSequence text, int newCursorPosition) {
     boolean result = super.commitText(text, newCursorPosition);
-    markDirty();
     return result;
   }
 
@@ -207,21 +201,18 @@ public boolean deleteSurroundingText(int beforeLength, int afterLength) {
     if (Selection.getSelectionStart(mEditable) == -1) return true;
 
     boolean result = super.deleteSurroundingText(beforeLength, afterLength);
-    markDirty();
     return result;
   }
 
   @Override
   public boolean deleteSurroundingTextInCodePoints(int beforeLength, int afterLength) {
     boolean result = super.deleteSurroundingTextInCodePoints(beforeLength, afterLength);
-    markDirty();
     return result;
   }
 
   @Override
   public boolean setComposingRegion(int start, int end) {
     boolean result = super.setComposingRegion(start, end);
-    markDirty();
     return result;
   }
 
@@ -233,7 +224,6 @@ public boolean setComposingText(CharSequence text, int newCursorPosition) {
     } else {
       result = super.setComposingText(text, newCursorPosition);
     }
-    markDirty();
     return result;
   }
 
@@ -255,7 +245,6 @@ public boolean finishComposingText() {
       }
     }
 
-    markDirty();
     return result;
   }
 
@@ -272,7 +261,6 @@ public ExtractedText getExtractedText(ExtractedTextRequest request, int flags) {
   @Override
   public boolean clearMetaKeyStates(int states) {
     boolean result = super.clearMetaKeyStates(states);
-    markDirty();
     return result;
   }
 
@@ -300,7 +288,6 @@ private boolean isSamsung() {
   @Override
   public boolean setSelection(int start, int end) {
     boolean result = super.setSelection(start, end);
-    markDirty();
     updateEditingState();
     return result;
   }
@@ -323,7 +310,6 @@ private static int clampIndexToEditable(int index, Editable editable) {
 
   @Override
   public boolean sendKeyEvent(KeyEvent event) {
-    markDirty();
     if (event.getAction() == KeyEvent.ACTION_DOWN) {
       if (event.getKeyCode() == KeyEvent.KEYCODE_DEL) {
         int selStart = clampIndexToEditable(Selection.getSelectionStart(mEditable), mEditable);
@@ -427,7 +413,6 @@ public boolean sendKeyEvent(KeyEvent event) {
 
   @Override
   public boolean performContextMenuAction(int id) {
-    markDirty();
     if (id == android.R.id.selectAll) {
       setSelection(0, mEditable.length());
       return true;
@@ -487,7 +472,6 @@ public boolean performPrivateCommand(String action, Bundle data) {
 
   @Override
   public boolean performEditorAction(int actionCode) {
-    markDirty();
     switch (actionCode) {
       case EditorInfo.IME_ACTION_NONE:
         textInputChannel.newline(mClient);

shell/platform/android/io/flutter/plugin/editing/TextInputPlugin.java

@@ -595,14 +595,13 @@ void setTextInputEditingState(View view, TextInputChannel.TextEditState state) {
     if (!state.text.equals(mEditable.toString())) {
       mEditable.replace(0, mEditable.length(), state.text);
     }
+
+    // Notify the autofill manager of the value change.
     notifyValueChanged(mEditable.toString());
     // Always apply state to selection which handles updating the selection if needed.
     applyStateToSelection(state);
-    InputConnection connection = getLastInputConnection();
-    if (connection != null && connection instanceof InputConnectionAdaptor) {
-      ((InputConnectionAdaptor) connection).markDirty();
-    }
-    // Use updateSelection to update imm on selection if it is not neccessary to restart.
+
+    // Use updateSelection to update imm on selection if it is not necessary to restart.
     if (!restartAlwaysRequired && !mRestartInputPending) {
       mImm.updateSelection(
           mView,
@@ -616,6 +615,12 @@ void setTextInputEditingState(View view, TextInputChannel.TextEditState state) {
       mImm.restartInput(view);
       mRestartInputPending = false;
     }
+
+    // Notify the connection adaptor that the last known remote editing state has been updated.
+    InputConnection connection = getLastInputConnection();
+    if (connection != null && connection instanceof InputConnectionAdaptor) {
+      ((InputConnectionAdaptor) connection).didUpdateEditingValue();
+    }
   }
 
   private interface MinMax {

shell/platform/android/test/io/flutter/plugin/editing/InputConnectionAdaptorTest.java

@@ -943,6 +943,46 @@ public void inputConnectionAdaptor_RepeatFilter() throws NullPointerException {
     assertEquals(textInputChannel.selectionEnd, 4);
   }
 
+  @Test
+  public void inputConnectionAdaptor_skipCallsAfterEditingValueUpdateFromFramework() {
+    View testView = new View(RuntimeEnvironment.application);
+    FlutterJNI mockFlutterJni = mock(FlutterJNI.class);
+    DartExecutor dartExecutor = spy(new DartExecutor(mockFlutterJni, mock(AssetManager.class)));
+    int inputTargetId = 0;
+    TestTextInputChannel textInputChannel = new TestTextInputChannel(dartExecutor);
+    AndroidKeyProcessor mockKeyProcessor = mock(AndroidKeyProcessor.class);
+    Editable mEditable = Editable.Factory.getInstance().newEditable("");
+    EditorInfo outAttrs = new EditorInfo();
+    outAttrs.inputType = InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_FLAG_MULTI_LINE;
+
+    InputConnectionAdaptor inputConnectionAdaptor =
+        new InputConnectionAdaptor(
+            testView, inputTargetId, textInputChannel, mockKeyProcessor, mEditable, outAttrs);
+
+    inputConnectionAdaptor.setComposingText("initial text", 1);
+    assertEquals(textInputChannel.text, "initial text");
+    // Calls updateEditingState.
+    inputConnectionAdaptor.beginBatchEdit();
+    inputConnectionAdaptor.endBatchEdit();
+    assertEquals(textInputChannel.text, "initial text");
+    // Do send update to the framework.
+    assertEquals(textInputChannel.updateEditingStateInvocations, 1);
+
+    // Change the internal state and pretend this is from the framework.
+    mEditable.replace(0, mEditable.length(), "updated text from the framework");
+    inputConnectionAdaptor.didUpdateEditingValue();
+    // Does not send update because it is the same as the state we just received.
+    assertEquals(textInputChannel.updateEditingStateInvocations, 1);
+
+    mEditable.replace(0, mEditable.length(), "yet another updated text from the framework");
+    // Calls updateEditingState.
+    inputConnectionAdaptor.beginBatchEdit();
+    inputConnectionAdaptor.endBatchEdit();
+    // Does send update because it is the same as the state we just received.
+    assertEquals(textInputChannel.text, "yet another updated text from the framework");
+    assertEquals(textInputChannel.updateEditingStateInvocations, 2);
+  }
+
   @Test
   public void testSendKeyEvent_delKeyDeletesBackward() {
     int selStart = 29;

shell/platform/android/test/io/flutter/plugin/editing/TextInputPluginTest.java

@@ -120,6 +120,46 @@ public void textInputPlugin_RequestsReattachOnCreation() throws JSONException {
     verifyMethodCall(bufferCaptor.getValue(), "TextInputClient.requestExistingInputState", null);
   }
 
+  @Test
+  public void setTextInputEditingState_doesNotInvokeUpdateEditingState() {
+    // Initialize a general TextInputPlugin.
+    InputMethodSubtype inputMethodSubtype = mock(InputMethodSubtype.class);
+    TestImm testImm =
+        Shadow.extract(
+            RuntimeEnvironment.application.getSystemService(Context.INPUT_METHOD_SERVICE));
+    testImm.setCurrentInputMethodSubtype(inputMethodSubtype);
+    View testView = new View(RuntimeEnvironment.application);
+    TextInputChannel textInputChannel = spy(new TextInputChannel(mock(DartExecutor.class)));
+    TextInputPlugin textInputPlugin =
+        new TextInputPlugin(testView, textInputChannel, mock(PlatformViewsController.class));
+    textInputPlugin.setTextInputClient(
+        0,
+        new TextInputChannel.Configuration(
+            false,
+            false,
+            true,
+            TextInputChannel.TextCapitalization.NONE,
+            null,
+            null,
+            null,
+            null,
+            null));
+
+    textInputPlugin.setTextInputEditingState(
+        testView, new TextInputChannel.TextEditState("initial input from framework", 0, 0));
+    assertTrue(textInputPlugin.getEditable().toString().equals("initial input from framework"));
+
+    verify(textInputChannel, times(0))
+        .updateEditingState(anyInt(), any(), anyInt(), anyInt(), anyInt(), anyInt());
+
+    textInputPlugin.setTextInputEditingState(
+        testView, new TextInputChannel.TextEditState("more update from the framwork", 1, 1));
+
+    assertTrue(textInputPlugin.getEditable().toString().equals("more update from the framwork"));
+    verify(textInputChannel, times(0))
+        .updateEditingState(anyInt(), any(), anyInt(), anyInt(), anyInt(), anyInt());
+  }
+
   @Test
   public void setTextInputEditingState_doesNotRestartWhenTextIsIdentical() {
     // Initialize a general TextInputPlugin.