1// Copyright (c) 2012 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 CHROME_BROWSER_UI_APP_MODAL_DIALOGS_APP_MODAL_DIALOG_QUEUE_H_
6#define CHROME_BROWSER_UI_APP_MODAL_DIALOGS_APP_MODAL_DIALOG_QUEUE_H_
7
8#include <deque>
9
10#include "base/basictypes.h"
11
12class AppModalDialog;
13
14template <typename T> struct DefaultSingletonTraits;
15
16// Keeps a queue of AppModalDialogs, making sure only one app modal
17// dialog is shown at a time.
18// This class is a singleton.
19class AppModalDialogQueue {
20 public:
21  typedef std::deque<AppModalDialog*>::iterator iterator;
22
23  // Returns the singleton instance.
24  static AppModalDialogQueue* GetInstance();
25
26  // Adds a modal dialog to the queue. If there are no other dialogs in the
27  // queue, the dialog will be shown immediately. Once it is shown, the
28  // most recently active browser window (or whichever is currently active)
29  // will be app modal, meaning it will be activated if the user tries to
30  // activate any other browser windows.
31  // Note: The AppModalDialog |dialog| must be window modal before it
32  // can be added as app modal.
33  void AddDialog(AppModalDialog* dialog);
34
35  // Removes the current dialog in the queue (the one that is being shown).
36  // Shows the next dialog in the queue, if any is present. This does not
37  // ensure that the currently showing dialog is closed, it just makes it no
38  // longer app modal.
39  void ShowNextDialog();
40
41  // Activates and shows the current dialog, if the user clicks on one of the
42  // windows disabled by the presence of an app modal dialog. This forces
43  // the window to be visible on the display even if desktop manager software
44  // opened the dialog on another virtual desktop. Assumes there is currently a
45  // dialog being shown. (Call BrowserList::IsShowingAppModalDialog to test
46  // this condition).
47  void ActivateModalDialog();
48
49  // Returns true if there is currently an active app modal dialog box.
50  bool HasActiveDialog() const;
51
52  AppModalDialog* active_dialog() { return active_dialog_; }
53
54  // Iterators to walk the queue. The queue does not include the currently
55  // active app modal dialog box.
56  iterator begin() { return app_modal_dialog_queue_.begin(); }
57  iterator end() { return app_modal_dialog_queue_.end(); }
58
59 private:
60  friend struct DefaultSingletonTraits<AppModalDialogQueue>;
61
62  AppModalDialogQueue();
63  ~AppModalDialogQueue();
64
65  // Shows |dialog| and notifies the BrowserList that a modal dialog is showing.
66  void ShowModalDialog(AppModalDialog* dialog);
67
68  // Returns the next dialog to show. This removes entries from
69  // app_modal_dialog_queue_ until one is valid or the queue is empty. This
70  // returns NULL if there are no more dialogs, or all the dialogs in the queue
71  // are not valid.
72  AppModalDialog* GetNextDialog();
73
74  // Contains all app modal dialogs which are waiting to be shown. The currently
75  // active modal dialog is not included.
76  std::deque<AppModalDialog*> app_modal_dialog_queue_;
77
78  // The currently active app-modal dialog box's delegate. NULL if there is no
79  // active app-modal dialog box.
80  AppModalDialog* active_dialog_;
81
82  // Stores if |ShowModalDialog()| is currently being called on an app-modal
83  // dialog.
84  bool showing_modal_dialog_;
85
86  DISALLOW_COPY_AND_ASSIGN(AppModalDialogQueue);
87};
88
89#endif  // CHROME_BROWSER_UI_APP_MODAL_DIALOGS_APP_MODAL_DIALOG_QUEUE_H_
90