ui/views/widget/root_view_targeter.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef UI_VIEWS_WIDGET_ROOT_VIEW_TARGETER_H_
   6 #define UI_VIEWS_WIDGET_ROOT_VIEW_TARGETER_H_
   7
   8 #include "ui/views/view_targeter.h"
   9 #include "ui/views/views_export.h"
  10
  11 namespace views {
  12
  13 namespace internal {
  14 class RootView;
  15 }  // namespace internal
  16
  17 class View;
  18 class ViewTargeterDelegate;
  19
  20 // A derived class of ViewTargeter that defines targeting logic for cases
  21 // needing to access the members of RootView. For example, when determining the
  22 // target of a gesture event, we need to know if a previous gesture has already
  23 // established the View to which all subsequent gestures should be targeted.
  24 class VIEWS_EXPORT RootViewTargeter : public ViewTargeter {
  25  public:
  26   RootViewTargeter(ViewTargeterDelegate* delegate,
  27                    internal::RootView* root_view);
  28   ~RootViewTargeter() override;
  29
  30  private:
  31   // ViewTargeter:
  32   View* FindTargetForGestureEvent(View* root,
  33                                   const ui::GestureEvent& gesture) override;
  34   ui::EventTarget* FindNextBestTargetForGestureEvent(
  35       ui::EventTarget* previous_target,
  36       const ui::GestureEvent& gesture) override;
  37
  38   // A pointer to the RootView on which |this| is installed.
  39   internal::RootView* root_view_;
  40
  41   DISALLOW_COPY_AND_ASSIGN(RootViewTargeter);
  42 };
  43
  44 }  // namespace views
  45
  46 #endif  // UI_VIEWS_WIDGET_ROOT_VIEW_TARGETER_H_