ui/message_center/views/message_list_view.h

// Copyright (c) 2015 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_MESSAGE_CENTER_VIEWS_MESSAGE_LIST_VIEW_H_
#define UI_MESSAGE_CENTER_VIEWS_MESSAGE_LIST_VIEW_H_

#include <list>
#include <set>
#include <vector>

#include "base/macros.h"
#include "ui/compositor/paint_context.h"
#include "ui/gfx/geometry/rect.h"
#include "ui/gfx/geometry/size.h"
#include "ui/message_center/message_center_export.h"
#include "ui/message_center/notification.h"
#include "ui/views/animation/bounds_animator.h"
#include "ui/views/animation/bounds_animator_observer.h"
#include "ui/views/controls/scroll_view.h"
#include "ui/views/view.h"

namespace ui {
class Layer;
}

namespace message_center {

class MessageView;

// Displays a list of messages for rich notifications. Functions as an array of
// MessageViews and animates them on transitions. It also supports
// repositioning.
class MESSAGE_CENTER_EXPORT MessageListView
    : public views::View,
      public views::BoundsAnimatorObserver {
 public:
  class Observer {
   public:
    virtual void OnAllNotificationsCleared() = 0;
  };

  MessageListView();
  ~MessageListView() override;

  void AddNotificationAt(MessageView* view, int i);
  void RemoveNotification(MessageView* view);
  void UpdateNotification(MessageView* view, const Notification& notification);
  void SetRepositionTarget(const gfx::Rect& target_rect);
  void ResetRepositionSession();
  void ClearAllClosableNotifications(const gfx::Rect& visible_scroll_rect);

  void AddObserver(Observer* observer);
  void RemoveObserver(Observer* observer);

  void SetRepositionTargetForTest(
      const gfx::Rect& target_rect);

  void set_scroller(views::ScrollView* scroller) { scroller_ = scroller; }

 protected:
  // Overridden from views::View.
  void Layout() override;
  gfx::Size GetPreferredSize() const override;
  int GetHeightForWidth(int width) const override;
  void PaintChildren(const ui::PaintContext& context) override;
  void ReorderChildLayers(ui::Layer* parent_layer) override;

  // Overridden from views::BoundsAnimatorObserver.
  void OnBoundsAnimatorProgressed(views::BoundsAnimator* animator) override;
  void OnBoundsAnimatorDone(views::BoundsAnimator* animator) override;

 private:
  friend class MessageCenterViewTest;
  friend class MessageListViewTest;

  bool IsValidChild(const views::View* child) const;
  void DoUpdateIfPossible();

  // Animates all notifications below target upwards to align with the top of
  // the last closed notification.
  void AnimateNotificationsBelowTarget();
  // Animates all notifications to align with the top of the last closed
  // notification.
  void AnimateNotifications();
  // Computes reposition offsets for |AnimateNotificationsAboveTarget|.
  std::vector<int> ComputeRepositionOffsets(const std::vector<int>& heights,
                                            const std::vector<bool>& deleting,
                                            int target_index,
                                            int padding);

  // Schedules animation for a child to the specified position. Returns false
  // if |child| will disappear after the animation.
  bool AnimateChild(views::View* child,
                    int top,
                    int height,
                    bool animate_even_on_move);

  // Calculate the new fixed height and update with it. |requested_height|
  // is the minimum height, and actual fixed height should be more than it.
  void UpdateFixedHeight(int requested_height, bool prevent_scroll);

  // Animate clearing one notification.
  void AnimateClearingOneNotification();

  // List of MessageListView::Observer
  base::ObserverList<Observer> observers_;

  // The top position of the reposition target rectangle.
  int reposition_top_;
  int fixed_height_;
  bool has_deferred_task_;
  bool clear_all_started_;
  std::set<views::View*> adding_views_;
  std::set<views::View*> deleting_views_;
  std::set<views::View*> deleted_when_done_;
  std::list<views::View*> clearing_all_views_;
  views::BoundsAnimator animator_;

  views::ScrollView* scroller_ = nullptr;

  // If true, the message loop will be quitted after the animation finishes.
  // This is just for tests and has no setter.
  bool quit_message_loop_after_animation_for_test_;

  base::WeakPtrFactory<MessageListView> weak_ptr_factory_;
  DISALLOW_COPY_AND_ASSIGN(MessageListView);
};

}  // namespace message_center

#endif  // UI_MESSAGE_CENTER_VIEWS_MESSAGE_LIST_VIEW_H_