1 #ifndef DALI_SIGNAL_DELEGATE_H
2 #define DALI_SIGNAL_DELEGATE_H
5 * Copyright (c) 2019 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/actors/actor.h>
23 #include <dali/public-api/signals/connection-tracker-interface.h>
29 * @brief The SignalDelegate object allows direct connection to a signal that has been pre-configured internally.
31 * EG: The SignalDelegate can be created internally and exposed to the application-developer.
32 * They can then call the connect function to transparently bind to their callback.
34 class DALI_CORE_API SignalDelegate
39 * @brief Create and set up a signal delegate.
41 * @param[in] connectActor The actor whose signal should be connected to.
42 * @param[in] signalName The name of the signal within the actor to connect to.
44 SignalDelegate( Dali::Actor connectActor, const std::string& signalName );
56 * @brief Connect to a FunctorDelegate as received from a type-registry signal connection call.
58 * This is required to allow connection to an actor's signal. Typically this is done in a generic
59 * way (IE. via a string of the signal name) using the ConnectSignal function.
60 * This function requires a functor.
62 * @param[in] connectionTracker Passed in to the ConnectSignal function of the actor.
63 * @param[in] functorDelegate A functor delegate object that must be executed when the signal is emitted.
64 * @return True of the connection was made, false otherwise.
66 bool Connect( ConnectionTrackerInterface* connectionTracker, FunctorDelegate* functorDelegate )
70 // Note: We have to new the CallbackBaseFunctor rather than have it as a concrete object, as it
71 // is converted to a FunctorDelegate again within ConnectSignal. FunctorDelegates gain ownership
72 // of any functor they are created from and therefore always attempt to delete them.
73 CallbackBaseFunctor* callbackFunctor = new CallbackBaseFunctor( new CallbackFunctorDelegate0( functorDelegate ) );
74 mConnectActor.ConnectSignal( connectionTracker, mSignalName, *callbackFunctor );
84 * @brief Connect to a non-static member function.
86 * The object that owns the member function must also inherit from ConnectionTracker.
88 * @param[in] object Object instance that houses the supplied member-function.
89 * @param[in] memberFunction The member-function to call when the signal is emitted.
90 * @return True of the connection was made, false otherwise.
93 bool Connect( T* object, void ( T::*memberFunction )( void ) )
97 CallbackBaseFunctor* callbackFunctor = new CallbackBaseFunctor( MakeCallback( object, memberFunction ) );
98 mConnectActor.ConnectSignal( object, mSignalName, *callbackFunctor );
108 * @brief Checks if this delegate has been connected yet, so it can be determined if it
109 * can be used or a new delegate must be created to set up a new connection (to the same signal).
111 * @return True if this SignalDelegate has been connected to it's signal.
119 * This functor is used by SignalDelegate in order to callback to a non-static member function
120 * (after it has been converted to a CallbackBase).
121 * The functor can be passed in to a ConnectSignal function of a BaseHandle and call into an
122 * object's member function on despatch.
124 struct CallbackBaseFunctor
127 * @brief Create and initialise the functor with the callback to be called.
129 * @param[in] callback A CallbackBase which can be created from a member function, or a FunctorDelegate.
131 CallbackBaseFunctor( CallbackBase* callback );
134 * @brief Executes the functor.
140 * Note that as this is passed in to a ConnectSignal method, it is converted to a FunctorDelegate.
141 * This means that this functor will automatically have it's destructor called, but we still own
142 * the CallbackBase, which must be destroyed manually here.
144 ~CallbackBaseFunctor();
148 CallbackBase* mCallback; ///< Stores (and owns) the callback to be called on execution.
154 * @brief Not defined.
156 SignalDelegate( const SignalDelegate& rhs );
159 * @brief Not defined.
161 const SignalDelegate& operator=( const SignalDelegate& rhs );
164 bool mIsConnected; ///< Boolean to know if it is connected already.
165 Dali::Actor mConnectActor; ///< The actor owning the signal to connect to.
166 std::string mSignalName; ///< The name of the signal to connect to.
171 #endif // DALI_SIGNAL_DELEGATE_H