Support for Adaptive Handle Orientation

content/public/android/java/src/org/chromium/content/browser/input/PopupTouchHandleDrawable.java

Index: content/public/android/java/src/org/chromium/content/browser/input/PopupTouchHandleDrawable.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/input/PopupTouchHandleDrawable.java b/content/public/android/java/src/org/chromium/content/browser/input/PopupTouchHandleDrawable.java
index 720534c628e6c35b71cb89f5870c755ce41a07f1..fbe3b0f85190ca96a54c3946bff5734b1c66b86e 100644
--- a/content/public/android/java/src/org/chromium/content/browser/input/PopupTouchHandleDrawable.java
+++ b/content/public/android/java/src/org/chromium/content/browser/input/PopupTouchHandleDrawable.java
@@ -50,6 +50,10 @@ public class PopupTouchHandleDrawable extends View {
     private int mParentPositionX;
     private int mParentPositionY;
 
+    // The mirror values based on which the handles are inverted
+    private boolean mMirrorHorizontal;
+    private boolean mMirrorVertical;
+
     // The offset from this handles position to the "tip" of the handle.
     private float mHotspotX;
     private float mHotspotY;
@@ -142,32 +146,37 @@ public class PopupTouchHandleDrawable extends View {
     }
 
     @CalledByNative
-    private void setOrientation(int orientation) {
+    private void setOrientation(int orientation, boolean mirrorVertical, boolean mirrorHorizontal) {
         assert (orientation >= TouchHandleOrientation.LEFT
                 && orientation <= TouchHandleOrientation.UNDEFINED);
-        if (mOrientation == orientation) return;
 
         final boolean hadValidOrientation = mOrientation != TouchHandleOrientation.UNDEFINED;
+        final boolean orientationChanged = mOrientation != orientation;
         mOrientation = orientation;
+        mMirrorHorizontal = mirrorHorizontal;
+        mMirrorVertical = mirrorVertical;
 
         final int oldAdjustedPositionX = getAdjustedPositionX();
         final int oldAdjustedPositionY = getAdjustedPositionY();
 
+        // Create new InvertedDrawable only if orientation has changed.
+        // Otherwise, change the mirror values to scale canvas on draw() calls.
+        if (orientationChanged) mDrawable = getHandleDrawable();
+
         switch (orientation) {
             case TouchHandleOrientation.LEFT: {
-                mDrawable = HandleViewResources.getLeftHandleDrawable(mContext);
-                mHotspotX = (mDrawable.getIntrinsicWidth() * 3) / 4f;
+                int drawableWidth = mDrawable.getIntrinsicWidth();
+                mHotspotX = mirrorHorizontal ? drawableWidth / 4f : (drawableWidth * 3) / 4f;

[jdduke (slow), 2015/06/19 14:33:58]

Hmm, it's a bit odd to have the handle padding come from HandleViewResources,
but to not use that value here?

[AviD, 2015/06/19 15:25:29]

mfomitchev suggested moving this logic of setting origin to TouchHandle.
I can update the logic in TouchHandle to use the values from
HandleViewResources.
Shall I do it in this patch or as a follow-up patch?

                 break;
             }
 
             case TouchHandleOrientation.RIGHT: {
-                mDrawable = HandleViewResources.getRightHandleDrawable(mContext);
-                mHotspotX = mDrawable.getIntrinsicWidth() / 4f;
+                int drawableWidth = mDrawable.getIntrinsicWidth();
+                mHotspotX = mirrorHorizontal ? (drawableWidth * 3) / 4f : drawableWidth / 4f;
                 break;
             }
 
             case TouchHandleOrientation.CENTER: {
-                mDrawable = HandleViewResources.getCenterHandleDrawable(mContext);
                 mHotspotX = mDrawable.getIntrinsicWidth() / 2f;
                 break;
             }
@@ -176,7 +185,8 @@ public class PopupTouchHandleDrawable extends View {
             default:
                 break;
         }
-        mHotspotY = 0;
+
+        mHotspotY = mirrorVertical ? mDrawable.getIntrinsicHeight() : 0;
 
         // Force handle repositioning to accommodate the new orientation's hotspot.
         if (hadValidOrientation) setFocus(oldAdjustedPositionX, oldAdjustedPositionY);
@@ -184,6 +194,27 @@ public class PopupTouchHandleDrawable extends View {
         scheduleInvalidate();
     }
 
+    private Drawable getHandleDrawable() {
+        switch (mOrientation) {
+            case TouchHandleOrientation.LEFT: {
+                return HandleViewResources.getLeftHandleDrawable(mContext);
+            }
+
+            case TouchHandleOrientation.RIGHT: {
+                return HandleViewResources.getRightHandleDrawable(mContext);
+            }
+
+            case TouchHandleOrientation.CENTER: {
+                return HandleViewResources.getCenterHandleDrawable(mContext);
+            }
+
+            case TouchHandleOrientation.UNDEFINED:
+            default:
+                assert false;
+                return HandleViewResources.getCenterHandleDrawable(mContext);
+        }
+    }
+
     private void updateParentPosition(int parentPositionX, int parentPositionY) {
         if (mParentPositionX == parentPositionX && mParentPositionY == parentPositionY) return;
         mParentPositionX = parentPositionX;
@@ -284,9 +315,17 @@ public class PopupTouchHandleDrawable extends View {
     @Override
     protected void onDraw(Canvas c) {
         if (mDrawable == null) return;
+        final boolean needsMirror = mMirrorHorizontal || mMirrorVertical;
+        if (needsMirror) {
+            c.save();
+            float scaleX = mMirrorHorizontal ? -1.f : 1.f;
+            float scaleY = mMirrorVertical ? -1.f : 1.f;
+            c.scale(scaleX, scaleY, getWidth() / 2.0f, getHeight() / 2.0f);
+        }
         updateAlpha();
         mDrawable.setBounds(0, 0, getRight() - getLeft(), getBottom() - getTop());
         mDrawable.draw(c);
+        if (needsMirror) c.restore();
     }
 
     // Returns the x coordinate of the position that the handle appears to be pointing to relative
@@ -373,6 +412,16 @@ public class PopupTouchHandleDrawable extends View {
     }
 
     @CalledByNative
+    private float getHandleVerticalPadding() {
+        return HandleViewResources.getHandleVerticalPadding();
+    }
+
+    @CalledByNative
+    private float getHandleHorizontalPadding() {
+        return HandleViewResources.getHandleHorizontalPadding();
+    }
+
+    @CalledByNative
     private int getPositionY() {
         return mPositionY;
     }