Improve time picker accessibility

Overrides click action description for TimePicker hour/minute selectors
and manually specifies traversal order for radial time picker nodes.

BUG: 17468036
Change-Id: I4472b42a95d762085d7a4d382feb2b9216c0d41c

2 files changed, 48 insertions, 0 deletions

diff --git a/core/java/android/widget/RadialTimePickerView.java b/core/java/android/widget/RadialTimePickerView.java
index 75c6184b0e46..7b64cf51835f 100644
--- a/core/java/android/widget/RadialTimePickerView.java
+++ b/core/java/android/widget/RadialTimePickerView.java
@@ -1456,6 +1456,32 @@ public class RadialTimePickerView extends View implements View.OnTouchListener {
 
             final boolean selected = isVirtualViewSelected(type, value);
             node.setSelected(selected);
+
+            final int nextId = getVirtualViewIdAfter(type, value);
+            if (nextId != INVALID_ID) {
+                node.setTraversalBefore(RadialTimePickerView.this, nextId);
+            }
+        }
+
+        private int getVirtualViewIdAfter(int type, int value) {
+            if (type == TYPE_HOUR) {
+                final int nextValue = value + 1;
+                final int max = mIs24HourMode ? 23 : 12;
+                if (nextValue <= max) {
+                    return makeId(type, nextValue);
+                }
+            } else if (type == TYPE_MINUTE) {
+                final int current = getCurrentMinute();
+                final int snapValue = value - (value % MINUTE_INCREMENT);
+                final int nextValue = snapValue + MINUTE_INCREMENT;
+                if (value < current && nextValue > current) {
+                    // The current value is between two snap values.
+                    return makeId(type, current);
+                } else if (nextValue < 60) {
+                    return makeId(type, nextValue);
+                }
+            }
+            return INVALID_ID;
         }
 
         @Override
diff --git a/core/java/android/widget/TimePickerClockDelegate.java b/core/java/android/widget/TimePickerClockDelegate.java
index d61b6fcb3680..8d475a7bde06 100644
--- a/core/java/android/widget/TimePickerClockDelegate.java
+++ b/core/java/android/widget/TimePickerClockDelegate.java
@@ -33,9 +33,11 @@ import android.view.KeyCharacterMap;
 import android.view.KeyEvent;
 import android.view.LayoutInflater;
 import android.view.View;
+import android.view.View.AccessibilityDelegate;
 import android.view.ViewGroup;
 import android.view.accessibility.AccessibilityEvent;
 import android.view.accessibility.AccessibilityNodeInfo;
+import android.view.accessibility.AccessibilityNodeInfo.AccessibilityAction;
 
 import com.android.internal.R;
 
@@ -136,9 +138,13 @@ class TimePickerClockDelegate extends TimePicker.AbstractTimePickerDelegate impl
         // Set up hour/minute labels.
         mHourView = (TextView) mHeaderView.findViewById(R.id.hours);
         mHourView.setOnClickListener(mClickListener);
+        mHourView.setAccessibilityDelegate(
+                new ClickActionDelegate(context, R.string.select_hours));
         mSeparatorView = (TextView) mHeaderView.findViewById(R.id.separator);
         mMinuteView = (TextView) mHeaderView.findViewById(R.id.minutes);
         mMinuteView.setOnClickListener(mClickListener);
+        mMinuteView.setAccessibilityDelegate(
+                new ClickActionDelegate(context, R.string.select_minutes));
 
         final int headerTimeTextAppearance = a.getResourceId(
                 R.styleable.TimePicker_headerTimeTextAppearance, 0);
@@ -206,6 +212,22 @@ class TimePickerClockDelegate extends TimePicker.AbstractTimePickerDelegate impl
         initialize(currentHour, currentMinute, false /* 12h */, HOUR_INDEX);
     }
 
+    private static class ClickActionDelegate extends AccessibilityDelegate {
+        private final AccessibilityAction mClickAction;
+
+        public ClickActionDelegate(Context context, int resId) {
+            mClickAction = new AccessibilityAction(
+                    AccessibilityNodeInfo.ACTION_CLICK, context.getString(resId));
+        }
+
+        @Override
+        public void onInitializeAccessibilityNodeInfo(View host, AccessibilityNodeInfo info) {
+            super.onInitializeAccessibilityNodeInfo(host, info);
+
+            info.addAction(mClickAction);
+        }
+    }
+
     private int computeStableWidth(TextView v, int maxNumber) {
         int maxWidth = 0;