1// Copyright (c) 2011 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_ACCESSIBLE_PANE_VIEW_H_
6#define UI_VIEWS_ACCESSIBLE_PANE_VIEW_H_
7
8#include "base/containers/hash_tables.h"
9#include "base/memory/scoped_ptr.h"
10#include "base/memory/weak_ptr.h"
11#include "ui/base/accelerators/accelerator.h"
12#include "ui/views/focus/focus_manager.h"
13#include "ui/views/view.h"
14
15namespace views {
16class FocusSearch;
17
18// This class provides keyboard access to any view that extends it, typically
19// a toolbar.  The user sets focus to a control in this view by pressing
20// F6 to traverse all panes, or by pressing a shortcut that jumps directly
21// to this pane.
22class VIEWS_EXPORT AccessiblePaneView : public View,
23                                        public FocusChangeListener,
24                                        public FocusTraversable {
25 public:
26  AccessiblePaneView();
27  virtual ~AccessiblePaneView();
28
29  // Set focus to the pane with complete keyboard access.
30  // Focus will be restored to the last focused view if the user escapes.
31  // If |initial_focus| is not NULL, that control will get
32  // the initial focus, if it's enabled and focusable. Returns true if
33  // the pane was able to receive focus.
34  virtual bool SetPaneFocus(View* initial_focus);
35
36  // Set focus to the pane with complete keyboard access, with the
37  // focus initially set to the default child. Focus will be restored
38  // to the last focused view if the user escapes.
39  // Returns true if the pane was able to receive focus.
40  virtual bool SetPaneFocusAndFocusDefault();
41
42  // Overridden from View:
43  virtual FocusTraversable* GetPaneFocusTraversable() OVERRIDE;
44  virtual bool AcceleratorPressed(const ui::Accelerator& accelerator)
45      OVERRIDE;
46  virtual void SetVisible(bool flag) OVERRIDE;
47  virtual void GetAccessibleState(ui::AXViewState* state) OVERRIDE;
48  virtual void RequestFocus() OVERRIDE;
49
50  // Overridden from FocusChangeListener:
51  virtual void OnWillChangeFocus(View* focused_before,
52                                 View* focused_now) OVERRIDE;
53  virtual void OnDidChangeFocus(View* focused_before,
54                                View* focused_now) OVERRIDE;
55
56  // Overridden from FocusTraversable:
57  virtual FocusSearch* GetFocusSearch() OVERRIDE;
58  virtual FocusTraversable* GetFocusTraversableParent() OVERRIDE;
59  virtual View* GetFocusTraversableParentView() OVERRIDE;
60
61  // For testing only.
62  const ui::Accelerator& home_key() const { return home_key_; }
63  const ui::Accelerator& end_key() const { return end_key_; }
64  const ui::Accelerator& escape_key() const { return escape_key_; }
65  const ui::Accelerator& left_key() const { return left_key_; }
66  const ui::Accelerator& right_key() const { return right_key_; }
67
68 protected:
69  // A subclass can override this to provide a default focusable child
70  // other than the first focusable child.
71  virtual View* GetDefaultFocusableChild();
72
73  // Returns the parent of |v|. Subclasses can override this if
74  // they need custom focus search behavior.
75  virtual View* GetParentForFocusSearch(View* v);
76
77  // Returns true if |v| is contained within the hierarchy rooted at |root|
78  // for the purpose of focus searching. Subclasses can override this if
79  // they need custom focus search behavior.
80  virtual bool ContainsForFocusSearch(View* root, const View* v);
81
82  // Remove pane focus.
83  virtual void RemovePaneFocus();
84
85  View* GetFirstFocusableChild();
86  View* GetLastFocusableChild();
87
88  FocusManager* focus_manager() const { return focus_manager_; }
89
90  // When finishing navigation by pressing ESC, it is allowed to surrender the
91  // focus to another window if if |allow| is set and no previous view can be
92  // found.
93  void set_allow_deactivate_on_esc(bool allow) {
94    allow_deactivate_on_esc_ = allow;
95  }
96
97 private:
98  bool pane_has_focus_;
99
100  // If true, the panel should be de-activated upon escape when no active view
101  // is known where to return to.
102  bool allow_deactivate_on_esc_;
103
104  // Save the focus manager rather than calling GetFocusManager(),
105  // so that we can remove focus listeners in the destructor.
106  FocusManager* focus_manager_;
107
108  // Our custom focus search implementation that traps focus in this
109  // pane and traverses all views that are focusable for accessibility,
110  // not just those that are normally focusable.
111  scoped_ptr<FocusSearch> focus_search_;
112
113  // Registered accelerators
114  ui::Accelerator home_key_;
115  ui::Accelerator end_key_;
116  ui::Accelerator escape_key_;
117  ui::Accelerator left_key_;
118  ui::Accelerator right_key_;
119
120  // View storage id for the last focused view that's not within this pane.
121  int last_focused_view_storage_id_;
122
123  friend class AccessiblePaneViewFocusSearch;
124
125  base::WeakPtrFactory<AccessiblePaneView> method_factory_;
126
127  DISALLOW_COPY_AND_ASSIGN(AccessiblePaneView);
128};
129
130}  // namespace views
131
132#endif  // UI_VIEWS_ACCESSIBLE_PANE_VIEW_H_
133