ash: Add an accelerator to clear the HUD.

BUG=none

Review URL: https://codereview.chromium.org/12093094

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@180005 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 19 insertions, 0 deletions

diff --git a/ash/touch/touch_observer_hud.cc b/ash/touch/touch_observer_hud.cc
index d6408c0..51809b0 100644
--- a/ash/touch/touch_observer_hud.cc
+++ b/ash/touch/touch_observer_hud.cc
@@ -87,6 +87,16 @@ class TouchHudCanvas : public views::View {
     SchedulePaint();
   }
 
+  void Clear() {
+    path_index_ = 0;
+    color_index_ = 0;
+    for (size_t i = 0; i < arraysize(paths_); ++i) {
+      paths_[i].reset();
+    }
+
+    SchedulePaint();
+  }
+
  private:
   // Overridden from views::View.
   virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE {
@@ -186,6 +196,11 @@ void TouchObserverHUD::ChangeToNextMode() {
   }
 }
 
+void TouchObserverHUD::Clear() {
+  if (widget_->IsVisible())
+    canvas_->Clear();
+}
+
 void TouchObserverHUD::UpdateTouchPointLabel(int index) {
   const char* status = NULL;
   switch (touch_status_[index]) {
diff --git a/ash/touch/touch_observer_hud.h b/ash/touch/touch_observer_hud.h
index 12dbe2b..3ae4e3d 100644
--- a/ash/touch/touch_observer_hud.h
+++ b/ash/touch/touch_observer_hud.h
@@ -36,6 +36,10 @@ class TouchObserverHUD : public ui::EventHandler,
   // cycles between a fixed number of display modes.
   void ChangeToNextMode();
 
+  // Removes all existing touch points from the screen (only if the HUD is
+  // visible).
+  void Clear();
+
  private:
   void UpdateTouchPointLabel(int index);