| // Copyright (c) 2011 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_VIEWS_FOCUS_EXTERNAL_FOCUS_TRACKER_H_ |
| #define UI_VIEWS_FOCUS_EXTERNAL_FOCUS_TRACKER_H_ |
| |
| #include "base/compiler_specific.h" |
| #include "base/macros.h" |
| #include "ui/views/focus/focus_manager.h" |
| |
| namespace views { |
| |
| class View; |
| class ViewTracker; |
| |
| // ExternalFocusTracker tracks the last focused view which belongs to the |
| // provided focus manager and is not either the provided parent view or one of |
| // its descendants. This is generally used if the parent view want to return |
| // focus to some other view once it is dismissed. The parent view and the focus |
| // manager must exist for the duration of the tracking. If the focus manager |
| // must be deleted before this object is deleted, make sure to call |
| // SetFocusManager(NULL) first. |
| // |
| // Typical use: When a view is added to the view hierarchy, it instantiates an |
| // ExternalFocusTracker and passes in itself and its focus manager. Then, |
| // when that view wants to return focus to the last focused view which is not |
| // itself and not a descandant of itself, (usually when it is being closed) |
| // it calls FocusLastFocusedExternalView. |
| class VIEWS_EXPORT ExternalFocusTracker : public FocusChangeListener { |
| public: |
| ExternalFocusTracker(View* parent_view, FocusManager* focus_manager); |
| ~ExternalFocusTracker() override; |
| |
| // FocusChangeListener: |
| void OnWillChangeFocus(View* focused_before, View* focused_now) override; |
| void OnDidChangeFocus(View* focused_before, View* focused_now) override; |
| |
| // Focuses last focused view which is not a child of parent view and is not |
| // parent view itself. Returns true if focus for a view was requested, false |
| // otherwise. |
| void FocusLastFocusedExternalView(); |
| |
| // Sets the focus manager whose focus we are tracking. |focus_manager| can |
| // be NULL, but no focus changes will be tracked. This is useful if the focus |
| // manager went away, but you might later want to start tracking with a new |
| // manager later, or call FocusLastFocusedExternalView to focus the previous |
| // view. |
| void SetFocusManager(FocusManager* focus_manager); |
| |
| private: |
| // Store the provided view. This view will be focused when |
| // FocusLastFocusedExternalView is called. |
| void StoreLastFocusedView(View* view); |
| |
| // Store the currently focused view for our view manager and register as a |
| // listener for future focus changes. |
| void StartTracking(); |
| |
| // Focus manager which we are a listener for. |
| FocusManager* focus_manager_; |
| |
| // The parent view of views which we should not track focus changes to. We |
| // also do not track changes to parent_view_ itself. |
| View* parent_view_; |
| |
| // Holds the last focused view. |
| std::unique_ptr<ViewTracker> last_focused_view_tracker_; |
| |
| DISALLOW_COPY_AND_ASSIGN(ExternalFocusTracker); |
| }; |
| |
| } // namespace views |
| |
| #endif // UI_VIEWS_FOCUS_EXTERNAL_FOCUS_TRACKER_H_ |