Set selection to end of text input on accessibility click

Summary:
When we render a text input that already has a text value (<TextInput value="123" />), its selection (cursor) is automatically set to the end of the text. However, when you swipe to focus the text input with TalkBack, Android decides it needs to clear the selection, which moves the cursor back to the beginning of the text input. This is probably not what you want if you're editing some text that's already there. Ideally we would just keep the selection at the end, but I don't know how to prevent this from happening - it seems to be part of how TextView handles the accessibility focus event? So instead I'm just explicitly setting the selection to the end of the text in our handler for accessibility click.

Changelog: [Android][Fixed] Move selection to the end of the text input on accessibility click

Reviewed By: mdvacca

Differential Revision: D23441077

fbshipit-source-id: 16964f5b106637e55a98c6b0ef0f0041e8e6215d

Author: Emily Janzer

ReactAndroid/src/androidTest/java/com/facebook/react/tests/TextInputTestCase.java

@@ -199,6 +199,37 @@ public void run() {
     assertFalse(reactEditText.isFocused());
   }
 
+  public void testAccessibilityFocus_notEmpty_selectionSetAtEnd() throws Throwable {
+    String testId = "textInput1";
+    String text = "Testing";
+
+    final ReactEditText reactEditText = getViewByTestId(testId);
+    reactEditText.setText(text);
+    runTestOnUiThread(
+        new Runnable() {
+          @Override
+          public void run() {
+            reactEditText.clearFocus();
+          }
+        });
+    waitForBridgeAndUIIdle();
+    assertFalse(reactEditText.isFocused());
+    assertEquals(0, reactEditText.getSelectionStart());
+
+    runTestOnUiThread(
+        new Runnable() {
+          @Override
+          public void run() {
+            reactEditText.performAccessibilityAction(
+                AccessibilityNodeInfo.ACTION_ACCESSIBILITY_FOCUS, null);
+            reactEditText.performAccessibilityAction(AccessibilityNodeInfo.ACTION_CLICK, null);
+          }
+        });
+    waitForBridgeAndUIIdle();
+    assertTrue(reactEditText.isFocused());
+    assertEquals(text.length(), reactEditText.getSelectionStart());
+  }
+
   private void fireEditorActionAndCheckRecording(
       final ReactEditText reactEditText, final int actionId) throws Throwable {
     fireEditorActionAndCheckRecording(reactEditText, actionId, true);

ReactAndroid/src/main/java/com/facebook/react/views/textinput/ReactEditText.java

@@ -145,6 +145,14 @@ public ReactEditText(Context context) {
           @Override
           public boolean performAccessibilityAction(View host, int action, Bundle args) {
             if (action == AccessibilityNodeInfo.ACTION_CLICK) {
+              int length = getText().length();
+              if (length > 0) {
+                // For some reason, when you swipe to focus on a text input that already has text in
+                // it, it clears the selection and resets the cursor to the beginning of the input.
+                // Since this is not typically (ever?) what you want, let's just explicitly set the
+                // selection on accessibility click to undo that.
+                setSelection(length);
+              }
               return requestFocusInternal();
             }
             return super.performAccessibilityAction(host, action, args);