1 #ifndef DALI_SIGNAL_SLOT_CONNECTIONS_H
2 #define DALI_SIGNAL_SLOT_CONNECTIONS_H
5 * Copyright (c) 2020 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/public-api/signals/callback.h>
23 #include <dali/public-api/signals/signal-slot-observers.h>
28 * @addtogroup dali_core_signals
34 * @brief Slot connection is the connection information held by a connection tracker.
36 * A slot can have zero to many connection objects, depending
37 * on how many signals it is connected to.
39 * A connection contains:
41 * - SlotObserver -interface provided by the signal
43 * It holds a pointer to the callback, but does not own it.
46 class DALI_CORE_API SlotConnection
53 * @param[in] slotObserver The slot observer
54 * @param[in] callback A callback object (not owned)
56 SlotConnection(SlotObserver* slotObserver, CallbackBase* callback);
59 * @brief Retrieves the callback.
62 * @return A pointer to the callback
64 CallbackBase* GetCallback() const
70 * @brief Retrieves the slot observer.
73 * @return A pointer to the slot observer
75 SlotObserver* GetSlotObserver() const
81 SlotObserver* mSlotObserver{nullptr}; ///< a pointer to the slot observer (not owned)
82 CallbackBase* mCallback{nullptr}; ///< The callback. This is not owned, the corresponding SignalConnection has ownership.
86 * @brief SignalConnection is the connection information held by the signal.
88 * A signal can have zero to many connections, depending on how
89 * many slots are connected to this signal.
91 * A connection contains:
93 * - SignalObserver - interface provided by a slot owning object.
95 * It takes ownership of the callback, and will delete it when
96 * the connection is destroyed.
99 class DALI_CORE_API SignalConnection
103 * @brief Constructor.
106 * @param[in] callback The callback which should be a C function
108 SignalConnection(CallbackBase* callback) noexcept
109 : mCallback(callback)
114 * @brief Constructor.
117 * @param[in] signalObserver The signal observer
118 * @param[in] callback Ownership of this callback object is taken
120 SignalConnection(SignalObserver* signalObserver, CallbackBase* callback) noexcept
121 : mSignalObserver(signalObserver),
127 * @brief Non-virtual destructor, not intended as a base class.
130 ~SignalConnection() noexcept
132 // signal connections have ownership of the callback.
137 * @brief Disconnects the signal from the slot.
140 * @param[in] slotObserver The signal disconnecting from the slot
142 void Disconnect(SlotObserver* slotObserver) noexcept;
145 * @brief Retrieves the callback.
148 * @return A pointer to the callback
150 CallbackBase* GetCallback() const noexcept
155 SignalConnection(const SignalConnection&) = delete; ///< Deleted copy constructor. @SINCE_1_0.0
156 SignalConnection& operator=(const SignalConnection&) = delete; ///< Deleted copy assignment operator. @SINCE_1_0.0
159 * @brief Move constructor.
161 * A move constructor enables the resources owned by an rvalue object to be moved into an lvalue without copying.
163 * @param[in] connection The property value to move from
165 SignalConnection(SignalConnection&& connection) noexcept
166 : mSignalObserver(connection.mSignalObserver),
167 mCallback(connection.mCallback)
169 connection.mSignalObserver = nullptr;
170 connection.mCallback = nullptr;
174 * @brief Move assignment operator.
177 * @param[in] connection The connection to move from
178 * @return a reference to this
180 SignalConnection& operator=(SignalConnection&& connection) noexcept
182 if(this != &connection)
184 // release the callback
187 mSignalObserver = connection.mSignalObserver;
188 mCallback = connection.mCallback;
190 connection.mSignalObserver = nullptr;
191 connection.mCallback = nullptr;
196 explicit operator bool() const noexcept
198 return mCallback ? true : false;
202 SignalObserver* mSignalObserver{nullptr}; ///< a pointer to the signal observer (not owned)
203 CallbackBase* mCallback{nullptr}; ///< The callback, has ownership.
211 #endif // DALI_SIGNAL_SLOT_CONNECTIONS_H