Add accessibility scroll support to some widgets.

1. Added support for accessibility scroll action to
   some widgets that are scrollable.

2. Making the super call when handling an accessibility
   action in the views to call super first to allow
   an accessibility delegate to intercept the call.

bug:5932640

Change-Id: I5eb37d64bf9fba1d5c596981132e0df717e2a18a

6 files changed, 90 insertions, 3 deletions

diff --git a/core/java/android/widget/AbsListView.java b/core/java/android/widget/AbsListView.java
index ab9d370..04c8cdc 100644
--- a/core/java/android/widget/AbsListView.java
+++ b/core/java/android/widget/AbsListView.java
@@ -1480,6 +1480,9 @@ public abstract class AbsListView extends AdapterView<ListAdapter> implements Te
 
     @Override
     public boolean performAccessibilityAction(int action, Bundle arguments) {
+        if (super.performAccessibilityAction(action, arguments)) {
+            return true;
+        }
         switch (action) {
             case AccessibilityNodeInfo.ACTION_SCROLL_FORWARD: {
                 if (getLastVisiblePosition() < getCount() - 1) {
@@ -1496,7 +1499,7 @@ public abstract class AbsListView extends AdapterView<ListAdapter> implements Te
                 }
             } return false;
         }
-        return super.performAccessibilityAction(action, arguments);
+        return false;
     }
 
     /**
diff --git a/core/java/android/widget/Gallery.java b/core/java/android/widget/Gallery.java
index 03fdc39..b2c8164 100644
--- a/core/java/android/widget/Gallery.java
+++ b/core/java/android/widget/Gallery.java
@@ -20,6 +20,7 @@ import android.annotation.Widget;
 import android.content.Context;
 import android.content.res.TypedArray;
 import android.graphics.Rect;
+import android.os.Bundle;
 import android.util.AttributeSet;
 import android.util.Log;
 import android.view.ContextMenu.ContextMenuInfo;
@@ -1367,6 +1368,35 @@ public class Gallery extends AbsSpinner implements GestureDetector.OnGestureList
     public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {
         super.onInitializeAccessibilityNodeInfo(info);
         info.setClassName(Gallery.class.getName());
+        info.setScrollable(mItemCount > 1);
+        if (mItemCount > 0 && mSelectedPosition < mItemCount - 1) {
+            info.addAction(AccessibilityNodeInfo.ACTION_SCROLL_FORWARD);
+        }
+        if (mItemCount > 0 && mSelectedPosition > 0) {
+            info.addAction(AccessibilityNodeInfo.ACTION_SCROLL_BACKWARD);
+        }
+    }
+
+    @Override
+    public boolean performAccessibilityAction(int action, Bundle arguments) {
+        if (super.performAccessibilityAction(action, arguments)) {
+            return true;
+        }
+        switch (action) {
+            case AccessibilityNodeInfo.ACTION_SCROLL_FORWARD: {
+                if (mItemCount > 0 && mSelectedPosition < mItemCount - 1) {
+                    final int currentChildIndex = mSelectedPosition - mFirstPosition;
+                    return scrollToChild(currentChildIndex + 1);
+                }
+            } return false;
+            case AccessibilityNodeInfo.ACTION_SCROLL_BACKWARD: {
+                if (mItemCount > 0 && mSelectedPosition > 0) {
+                    final int currentChildIndex = mSelectedPosition - mFirstPosition;
+                    return scrollToChild(currentChildIndex - 1);
+                }
+            } return false;
+        }
+        return false;
     }
 
     /**
diff --git a/core/java/android/widget/HorizontalScrollView.java b/core/java/android/widget/HorizontalScrollView.java
index ffabd1d..f889cb7 100644
--- a/core/java/android/widget/HorizontalScrollView.java
+++ b/core/java/android/widget/HorizontalScrollView.java
@@ -739,6 +739,9 @@ public class HorizontalScrollView extends FrameLayout {
 
     @Override
     public boolean performAccessibilityAction(int action, Bundle arguments) {
+        if (super.performAccessibilityAction(action, arguments)) {
+            return true;
+        }
         switch (action) {
             case AccessibilityNodeInfo.ACTION_SCROLL_FORWARD: {
                 final int viewportWidth = getWidth() - mPaddingLeft - mPaddingRight;
@@ -757,7 +760,7 @@ public class HorizontalScrollView extends FrameLayout {
                 }
             } return false;
         }
-        return super.performAccessibilityAction(action, arguments);
+        return false;
     }
 
     @Override
diff --git a/core/java/android/widget/NumberPicker.java b/core/java/android/widget/NumberPicker.java
index 78d570e..b825e1b 100644
--- a/core/java/android/widget/NumberPicker.java
+++ b/core/java/android/widget/NumberPicker.java
@@ -2172,6 +2172,18 @@ public class NumberPicker extends LinearLayout {
                             }
                             return false;
                         }
+                        case AccessibilityNodeInfo.ACTION_SCROLL_FORWARD: {
+                            if (getWrapSelectorWheel() || getValue() < getMaxValue()) {
+                                changeValueByOne(true);
+                                return true;
+                            }
+                        } return false;
+                        case AccessibilityNodeInfo.ACTION_SCROLL_BACKWARD: {
+                            if (getWrapSelectorWheel() || getValue() > getMinValue()) {
+                                changeValueByOne(false);
+                                return true;
+                            }
+                        } return false;
                     }
                 } break;
                 case VIRTUAL_VIEW_ID_INPUT: {
@@ -2497,6 +2509,12 @@ public class NumberPicker extends LinearLayout {
             if (mAccessibilityFocusedView == View.NO_ID) {
                 info.addAction(AccessibilityNodeInfo.ACTION_CLEAR_ACCESSIBILITY_FOCUS);
             }
+            if (getWrapSelectorWheel() || getValue() < getMaxValue()) {
+                info.addAction(AccessibilityNodeInfo.ACTION_SCROLL_FORWARD);
+            }
+            if (getWrapSelectorWheel() || getValue() > getMinValue()) {
+                info.addAction(AccessibilityNodeInfo.ACTION_SCROLL_BACKWARD);
+            }
 
             return info;
         }
diff --git a/core/java/android/widget/ScrollView.java b/core/java/android/widget/ScrollView.java
index b398ce4..a499743 100644
--- a/core/java/android/widget/ScrollView.java
+++ b/core/java/android/widget/ScrollView.java
@@ -742,6 +742,9 @@ public class ScrollView extends FrameLayout {
 
     @Override
     public boolean performAccessibilityAction(int action, Bundle arguments) {
+        if (super.performAccessibilityAction(action, arguments)) {
+            return true;
+        }
         switch (action) {
             case AccessibilityNodeInfo.ACTION_SCROLL_FORWARD: {
                 final int viewportHeight = getHeight() - mPaddingBottom - mPaddingTop;
@@ -760,7 +763,7 @@ public class ScrollView extends FrameLayout {
                 }
             } return false;
         }
-        return super.performAccessibilityAction(action, arguments);
+        return false;
     }
 
     @Override
diff --git a/core/java/android/widget/StackView.java b/core/java/android/widget/StackView.java
index 22df3bc..dd0915b 100644
--- a/core/java/android/widget/StackView.java
+++ b/core/java/android/widget/StackView.java
@@ -32,6 +32,7 @@ import android.graphics.Rect;
 import android.graphics.RectF;
 import android.graphics.Region;
 import android.graphics.TableMaskFilter;
+import android.os.Bundle;
 import android.util.AttributeSet;
 import android.util.Log;
 import android.view.InputDevice;
@@ -1228,6 +1229,35 @@ public class StackView extends AdapterViewAnimator {
     public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {
         super.onInitializeAccessibilityNodeInfo(info);
         info.setClassName(StackView.class.getName());
+        info.setScrollable(getChildCount() > 1);
+        if (getDisplayedChild() < getChildCount() - 1) {
+            info.addAction(AccessibilityNodeInfo.ACTION_SCROLL_FORWARD);
+        }
+        if (getDisplayedChild() > 0) {
+            info.addAction(AccessibilityNodeInfo.ACTION_SCROLL_BACKWARD);
+        }
+    }
+
+    @Override
+    public boolean performAccessibilityAction(int action, Bundle arguments) {
+        if (super.performAccessibilityAction(action, arguments)) {
+            return true;
+        }
+        switch (action) {
+            case AccessibilityNodeInfo.ACTION_SCROLL_FORWARD: {
+                if (getDisplayedChild() < getChildCount() - 1) {
+                    showNext();
+                    return true;
+                }
+            } return false;
+            case AccessibilityNodeInfo.ACTION_SCROLL_BACKWARD: {
+                if (getDisplayedChild() > 0) {
+                    showPrevious();
+                    return true;
+                }
+            } return false;
+        }
+        return false;
     }
 
     class LayoutParams extends ViewGroup.LayoutParams {