Drag and drop between app list and launcher - First patch

ui/app_list/views/app_list_drag_and_drop_host.h

Index: ui/app_list/views/app_list_drag_and_drop_host.h
diff --git a/ui/app_list/views/app_list_drag_and_drop_host.h b/ui/app_list/views/app_list_drag_and_drop_host.h
new file mode 100644
index 0000000000000000000000000000000000000000..3da9cf77c605a5b7749dc89684fcb5607a81dcb1
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+++ b/ui/app_list/views/app_list_drag_and_drop_host.h
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+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef UI_APP_LIST_VIEWS_APP_LIST_DRAG_AND_DROP_HOST_H_
+#define UI_APP_LIST_VIEWS_APP_LIST_DRAG_AND_DROP_HOST_H_
+
+#include <string>
+
+namespace gfx {
+class Point;
+}  // namespace gfx
+
+namespace app_list {
+
+// This class will get used by the AppListView to drag and drop Application
+// shortcuts onto another host (the launcher).
+class ApplicationDragAndDropHost {
+ public:
+  // A drag operation could get started. The recipient has to return true if
+  // he wants to take it - e.g. |location_in_screen_poordinates| is over a
+  // target area. The passed |app_id| identifies the application which should
+  // get dropped.
+  virtual bool StartDrag(const std::string& app_id,
+                         const gfx::Point& location_in_screen_coordinates) = 0;
+
+  // This gets only called when the |StartDrag| function returned true and it
+  // dispatches the mouse coordinate change accordingly. When the function
+  // returns false it requests that the operation be aborted since the event
+  // location is out of bounds.
+  virtual bool Drag(const gfx::Point& location_in_screen_coordinates) = 0;
+
+  // Once |StartDrag| returned true, this function is guaranteed to be called
+  // when the mouse / touch events stop. If |cancel| is set, the drag operation
+  // was aborted, otherwise the change should be kept.
+  virtual void EndDrag(bool cancel) = 0;
+};
+
+}  // namespace app_list
+
+#endif  // UI_APP_LIST_VIEWS_APP_LIST_DRAG_AND_DROP_HOST_H_