Refactor intra-strip panel drags by introducing PanelDragController.

chrome/browser/ui/panels/detached_panel_strip.h

Index: chrome/browser/ui/panels/detached_panel_strip.h
diff --git a/chrome/browser/ui/panels/detached_panel_strip.h b/chrome/browser/ui/panels/detached_panel_strip.h
index 868093bd59a237e6e9b9179bcf6b384d90b86932..c50d24b79340ca0af6b8c414d7cd7b448bdc920c 100644
--- a/chrome/browser/ui/panels/detached_panel_strip.h
+++ b/chrome/browser/ui/panels/detached_panel_strip.h
@@ -10,6 +10,7 @@
 #include "base/basictypes.h"
 #include "chrome/browser/ui/panels/panel.h"
 #include "chrome/browser/ui/panels/panel_strip.h"
+#include "ui/gfx/point.h"
 #include "ui/gfx/rect.h"
 
 class Browser;
@@ -36,6 +37,10 @@ class DetachedPanelStrip : public PanelStrip {
   virtual void ActivatePanel(Panel* panel) OVERRIDE;
   virtual void MinimizePanel(Panel* panel) OVERRIDE;
   virtual void RestorePanel(Panel* panel) OVERRIDE;
+  virtual bool CanDragPanel(Panel* panel) const OVERRIDE;
+  virtual void StartDraggingPanel(Panel* panel) OVERRIDE;
+  virtual void DragPanel(int delta_x, int delta_y) OVERRIDE;
+  virtual void EndDraggingPanel(bool cancelled) OVERRIDE;
 
   int num_panels() const { return panels_.size(); }
   const Panels& panels() const { return panels_; }
@@ -49,6 +54,10 @@ class DetachedPanelStrip : public PanelStrip {
   // Collection of all panels.
   Panels panels_;
 
+  // Original position of the panel being dragged. This is used to get back to
+  // the original position when we cancel the dragging.
+  gfx::Point dragging_panel_original_position_;

[jennb, 2012/02/17 21:28:45]

This feels like it belongs in drag controller. 

Also, which coordinate system?

[jianli, 2012/02/17 23:52:56]

Done.

+
   DISALLOW_COPY_AND_ASSIGN(DetachedPanelStrip);
 };