Support for Adaptive Handle Orientation

ui/touch_selection/touch_handle.h

Index: ui/touch_selection/touch_handle.h
diff --git a/ui/touch_selection/touch_handle.h b/ui/touch_selection/touch_handle.h
index 12c66d09983626db3c3f9b4a356aa80a2a9d9178..6bcf4e8834fa896716049f5d0f937dae95c99fd8 100644
--- a/ui/touch_selection/touch_handle.h
+++ b/ui/touch_selection/touch_handle.h
@@ -24,9 +24,11 @@ class UI_TOUCH_SELECTION_EXPORT TouchHandleDrawable {
  public:
   virtual ~TouchHandleDrawable() {}
   virtual void SetEnabled(bool enabled) = 0;
-  virtual void SetOrientation(TouchHandleOrientation orientation) = 0;
+  virtual void SetLayout(const gfx::PointF& position,
+                         ui::TouchHandleOrientation orientation,
+                         bool mirror_vertical,
+                         bool mirror_horizontal) = 0;
   virtual void SetAlpha(float alpha) = 0;
-  virtual void SetFocus(const gfx::PointF& position) = 0;
   virtual gfx::RectF GetVisibleBounds() const = 0;
 };
 
@@ -66,10 +68,14 @@ class UI_TOUCH_SELECTION_EXPORT TouchHandle {
   // If an animation is in-progress, it will be overriden appropriately.
   void SetVisible(bool visible, AnimationStyle animation_style);
 
-  // Update the handle placement to |position|.
+  // Update the focus points for the handles. The Handle will be positioned
+  // either |top| or |bottom| based on the mirror parameters.
   // Note: If a fade out animation is active or the handle is invisible, the
   // handle position will not be updated until the handle regains visibility.
-  void SetPosition(const gfx::PointF& position);
+  void SetFocus(const gfx::PointF& top, const gfx::PointF& bottom);

[mfomitchev, 2015/05/13 22:19:14]

We always call both SetFocus and SetViewportRect, and we end up doing the layout
twice. Can we combine these methods into one like we did for
CompositedTouchHandleDrawable?

[jdduke (slow), 2015/05/14 15:20:10]

Hmm, but we would only do the layout twice if the viewport size changes
(hopefully infrequent?). Don't have a problem merging the two calls, not sure
what the best name would be.

[AviD, 2015/05/19 16:26:28]

SetSelectionParams() ?

[AviD, 2015/05/21 09:23:14]

I have changed this to update the viewport rect only if it changes and active
selection/insertion is present, instead of updating for every selectionChanged()
event.

+
+  // Update the Viewport rect, based on which the handle decide its inversion
+  void SetViewportRect(const gfx::RectF viewport_rect);
 
   // Update the handle visuals to |orientation|.
   // Note: If the handle is being dragged, the orientation change will be
@@ -85,10 +91,11 @@ class UI_TOUCH_SELECTION_EXPORT TouchHandle {
   bool Animate(base::TimeTicks frame_time);
 
   bool is_dragging() const { return is_dragging_; }
-  const gfx::PointF& position() const { return position_; }
+  const gfx::PointF& position() const { return focus_bottom_; }

[mfomitchev, 2015/05/13 22:19:14]

rename to focus_bottom()?

[AviD, 2015/05/19 16:26:28]

Done.

   TouchHandleOrientation orientation() const { return orientation_; }
 
  private:
+  void UpdateLayout();
   void BeginDrag();
   void EndDrag();
   void BeginFade();
@@ -99,7 +106,9 @@ class UI_TOUCH_SELECTION_EXPORT TouchHandle {
 
   TouchHandleClient* const client_;
 
-  gfx::PointF position_;
+  gfx::PointF focus_bottom_;
+  gfx::PointF focus_top_;
+  gfx::RectF viewport_rect_;
   TouchHandleOrientation orientation_;
   TouchHandleOrientation deferred_orientation_;
 
@@ -120,6 +129,10 @@ class UI_TOUCH_SELECTION_EXPORT TouchHandle {
   bool is_dragging_;
   bool is_drag_within_tap_region_;
 
+  // Mirror variables determine if the handles should be inverted or not.
+  bool mirror_vertical_;
+  bool mirror_horizontal_;
+
   DISALLOW_COPY_AND_ASSIGN(TouchHandle);
 };