1 #ifndef __DALI_TOOLKIT_KEYINPUT_FOCUS_MANAGER_H__
2 #define __DALI_TOOLKIT_KEYINPUT_FOCUS_MANAGER_H__
5 * Copyright (c) 2014 Samsung Electronics Co., Ltd.
7 * Licensed under the Apache License, Version 2.0 (the "License");
8 * you may not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
11 * http://www.apache.org/licenses/LICENSE-2.0
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
22 #include <dali-toolkit/public-api/controls/control.h>
30 namespace Internal DALI_INTERNAL
32 class KeyInputFocusManager;
36 * KeyInputFocusManager
37 * This class provides the functionality of registering for keyboard events for controls.
38 * The keyinput focus manager maintains a stack of controls, With the last added control receiving
39 * all the keyboard events first. And if the conrol doesn't consume the event it is passed to
40 * the next control in the stack. If none of the controls in the stack consume the key event then
41 * UnhandledKeyEventSignal() is emitted.
43 class DALI_IMPORT_API KeyInputFocusManager : public BaseHandle
47 static const char* const SIGNAL_KEY_INPUT_FOCUS_CHANGED;
48 static const char* const SIGNAL_UNHANDLED_KEY_EVENT;
50 // KeyInputFocusChanged
51 typedef Signal< void (Control, Control) > KeyInputFocusChangedSignalType;
53 // Unhandled Key Event
54 typedef Signal< void (const KeyEvent&) > UnhandledKeyEventSignalType;
59 * Create a KeyInputFocusManager handle; this can be initialised with KeyInputFocusManager::Get()
60 * Calling member functions with an uninitialised handle is not allowed.
62 KeyInputFocusManager();
67 * This is non-virtual since derived Handle types must not contain data or virtual methods.
69 ~KeyInputFocusManager();
72 * Get the singleton of KeyInputFocusManager object.
73 * @return A handle to the KeyInputFocusManager control.
75 static KeyInputFocusManager Get();
78 * Sets keyboard focus for a control.
79 * Note: A control can be set to be in focus and still not receive all the key events if another control has over ridden it.
80 * As the key input focus mechanism works like a stack, the top most control receives all the key events, and passes on the
81 * unhandled events to the controls below in the stack. A control in the stack will regain key input focus when there are no more
82 * controls above it in the focus stack.
84 * @pre The Control is not in the focus stack. If it is allready present in the top of the stack it results in a no-op, If it is
85 * present in the stack but not on the top of the stack, then the control is moved to the top of the focus stack.
86 * @param[in] control The Control to receive keyboard input
88 void SetFocus(Control control);
91 * Query for the control that is currently set to be on top of the fcous stack and receives all
92 * keyboard input events first.
93 * @return Pointer to the control set to receive keyboard inputs.
95 Control GetCurrentFocusControl() const;
98 * Removes focus for the given control, The control will no longer receive events from keyboard.
99 * @param [in] control which should be removed from focus.
101 void RemoveFocus(Control control);
104 * Queries whether a control is currently part of the focus stack.
105 * @param [in] control which should be queried.
106 * @return True if it is part of the foucus stack False otherwise.
108 bool IsKeyboardListener(Control control);
113 * This signal is emitted when the key input focus control changes.
114 * Two control parameters are sent as part of this signal, the first being the signal that now has the focus, the second
115 * being the one that has lost focus.
116 * A callback of the following type may be connected:
118 * void YourCallback(Control focusGainedControl, Control focusLostActor);
120 * @return The signal to connect to.
122 KeyInputFocusChangedSignalType& KeyInputFocusChangedSignal();
125 * This signal is emitted when a key event was received, and none of the focused controls on the stage have consumed it.
126 * A callback of the following type may be connected:
128 * void YourCallbackName(const KeyEvent& event);
130 * @return The signal to connect to.
132 UnhandledKeyEventSignalType& UnhandledKeyEventSignal();
136 explicit DALI_INTERNAL KeyInputFocusManager(Internal::KeyInputFocusManager *impl);
138 }; // class KeyInputFocusManager
140 } // namespace Toolkit
144 #endif // __DALI_TOOLKIT_KEYINPUT_FOCUS_MANAGER_H__