blob: deaaab447ce1346e87885bacb7cdb93b09b795e2 [file] [log] [blame]
// 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_WIDGET_FOCUS_MANAGER_H_
#define UI_VIEWS_FOCUS_WIDGET_FOCUS_MANAGER_H_
#include "base/macros.h"
#include "base/observer_list.h"
#include "ui/gfx/native_widget_types.h"
#include "ui/views/views_export.h"
namespace base {
template <typename T> struct DefaultSingletonTraits;
}
namespace views {
// This interface should be implemented by classes that want to be notified when
// the native focus is about to change. Listeners implementing this interface
// will be invoked for all native focus changes across the entire Chrome
// application. FocusChangeListeners are only called for changes within the
// children of a single top-level native-view.
class WidgetFocusChangeListener {
public:
virtual void OnNativeFocusChanged(gfx::NativeView focused_now) = 0;
protected:
virtual ~WidgetFocusChangeListener() {}
};
class VIEWS_EXPORT WidgetFocusManager {
public:
// Returns the singleton instance.
static WidgetFocusManager* GetInstance();
// Adds/removes a WidgetFocusChangeListener |listener| to the set of
// active listeners.
void AddFocusChangeListener(WidgetFocusChangeListener* listener);
void RemoveFocusChangeListener(WidgetFocusChangeListener* listener);
// Called when native-focus shifts within, or off, a widget. |focused_now| is
// null when focus is lost.
void OnNativeFocusChanged(gfx::NativeView focused_now);
// Enable/Disable notification of registered listeners during calls
// to OnNativeFocusChanged. Used to prevent unwanted focus changes from
// propagating notifications.
void EnableNotifications() { enabled_ = true; }
void DisableNotifications() { enabled_ = false; }
private:
friend struct base::DefaultSingletonTraits<WidgetFocusManager>;
WidgetFocusManager();
~WidgetFocusManager();
base::ObserverList<WidgetFocusChangeListener> focus_change_listeners_;
bool enabled_;
DISALLOW_COPY_AND_ASSIGN(WidgetFocusManager);
};
// A basic helper class that is used to disable native focus change
// notifications within a scope.
class VIEWS_EXPORT AutoNativeNotificationDisabler {
public:
AutoNativeNotificationDisabler();
~AutoNativeNotificationDisabler();
private:
DISALLOW_COPY_AND_ASSIGN(AutoNativeNotificationDisabler);
};
} // namespace views
#endif // UI_VIEWS_FOCUS_WIDGET_FOCUS_MANAGER_H_