Text traversal at various granularities.

1. Implementing text content navigation at various granularities.
   For views that have content description but no text the
   content description is the traversed at character and word
   granularities. For views that inherit from TextView the
   supported granularities are character, word, line, and page.

bug:5932640

Conflicts:

	core/java/android/view/View.java

Conflicts:

	core/java/android/view/View.java

Change-Id: I66d1e16ce9ac5d6b49f036b17c087b2a7075e4c0

1 files changed, 89 insertions, 4 deletions

diff --git a/core/java/android/widget/TextView.java b/core/java/android/widget/TextView.java
index 8c81343..f2334ae 100644
--- a/core/java/android/widget/TextView.java
+++ b/core/java/android/widget/TextView.java
@@ -26,7 +26,6 @@ import android.content.res.Resources;
 import android.content.res.TypedArray;
 import android.content.res.XmlResourceParser;
 import android.graphics.Canvas;
-import android.graphics.Color;
 import android.graphics.Paint;
 import android.graphics.Path;
 import android.graphics.Rect;
@@ -91,6 +90,7 @@ import android.util.AttributeSet;
 import android.util.FloatMath;
 import android.util.Log;
 import android.util.TypedValue;
+import android.view.AccessibilityIterators.TextSegmentIterator;
 import android.view.ActionMode;
 import android.view.DragEvent;
 import android.view.Gravity;
@@ -7712,6 +7712,17 @@ public class TextView extends View implements ViewTreeObserver.OnPreDrawListener
         if (!isPassword) {
             info.setText(getTextForAccessibility());
         }
+
+        if (TextUtils.isEmpty(getContentDescription())
+                && !TextUtils.isEmpty(mText)) {
+            info.addAction(AccessibilityNodeInfo.ACTION_NEXT_AT_MOVEMENT_GRANULARITY);
+            info.addAction(AccessibilityNodeInfo.ACTION_PREVIOUS_AT_MOVEMENT_GRANULARITY);
+            info.setMovementGranularities(AccessibilityNodeInfo.MOVEMENT_GRANULARITY_CHARACTER
+                    | AccessibilityNodeInfo.MOVEMENT_GRANULARITY_WORD
+                    | AccessibilityNodeInfo.MOVEMENT_GRANULARITY_LINE
+                    | AccessibilityNodeInfo.MOVEMENT_GRANULARITY_PARAGRAPH
+                    | AccessibilityNodeInfo.MOVEMENT_GRANULARITY_PAGE);
+        }
     }
 
     @Override
@@ -7726,12 +7737,13 @@ public class TextView extends View implements ViewTreeObserver.OnPreDrawListener
     }
 
     /**
-     * Gets the text reported for accessibility purposes. It is the
-     * text if not empty or the hint.
+     * Gets the text reported for accessibility purposes.
      *
      * @return The accessibility text.
+     *
+     * @hide
      */
-    private CharSequence getTextForAccessibility() {
+    public CharSequence getTextForAccessibility() {
         CharSequence text = getText();
         if (TextUtils.isEmpty(text)) {
             text = getHint();
@@ -8287,6 +8299,79 @@ public class TextView extends View implements ViewTreeObserver.OnPreDrawListener
     }
 
     /**
+     * @hide
+     */
+    @Override
+    public CharSequence getIterableTextForAccessibility() {
+        if (getContentDescription() == null) {
+            if (!(mText instanceof Spannable)) {
+                setText(mText, BufferType.SPANNABLE);
+            }
+            return mText;
+        }
+        return super.getIterableTextForAccessibility();
+    }
+
+    /**
+     * @hide
+     */
+    @Override
+    public TextSegmentIterator getIteratorForGranularity(int granularity) {
+        switch (granularity) {
+            case AccessibilityNodeInfo.MOVEMENT_GRANULARITY_LINE: {
+                Spannable text = (Spannable) getIterableTextForAccessibility();
+                if (!TextUtils.isEmpty(text) && getLayout() != null) {
+                    AccessibilityIterators.LineTextSegmentIterator iterator =
+                        AccessibilityIterators.LineTextSegmentIterator.getInstance();
+                    iterator.initialize(text, getLayout());
+                    return iterator;
+                }
+            } break;
+            case AccessibilityNodeInfo.MOVEMENT_GRANULARITY_PAGE: {
+                Spannable text = (Spannable) getIterableTextForAccessibility();
+                if (!TextUtils.isEmpty(text) && getLayout() != null) {
+                    AccessibilityIterators.PageTextSegmentIterator iterator =
+                        AccessibilityIterators.PageTextSegmentIterator.getInstance();
+                    iterator.initialize(this);
+                    return iterator;
+                }
+            } break;
+        }
+        return super.getIteratorForGranularity(granularity);
+    }
+
+    /**
+     * @hide
+     */
+    @Override
+    public int getAccessibilityCursorPosition() {
+        if (TextUtils.isEmpty(getContentDescription())) {
+            return getSelectionEnd();
+        } else {
+            return super.getAccessibilityCursorPosition();
+        }
+    }
+
+    /**
+     * @hide
+     */
+    @Override
+    public void setAccessibilityCursorPosition(int index) {
+        if (getAccessibilityCursorPosition() == index) {
+            return;
+        }
+        if (TextUtils.isEmpty(getContentDescription())) {
+            if (index >= 0) {
+                Selection.setSelection((Spannable) mText, index);
+            } else {
+                Selection.removeSelection((Spannable) mText);
+            }
+        } else {
+            super.setAccessibilityCursorPosition(index);
+        }
+    }
+
+    /**
      * User interface state that is stored by TextView for implementing
      * {@link View#onSaveInstanceState}.
      */