织梦做的相亲网站,口碑营销的产品有哪些,网站在百度的图标显示不正常,wordpress jquery 插件Qt的信号与槽主要是为了对象之间的信号传递#xff0c;以达到某种交互操作的功能。我按照自己的理解逐步实现这样的效果。 步骤一#xff1a; 第一个类#xff08;接收者#xff09;的成员函数实现某种功能#xff0c;第二个类#xff08;发送者#xff09;定义一个对象…        Qt的信号与槽主要是为了对象之间的信号传递以达到某种交互操作的功能。我按照自己的理解逐步实现这样的效果。 步骤一 第一个类接收者的成员函数实现某种功能第二个类发送者定义一个对象指针初始化后达到间接访问类1接收者)的成员函数。运行后显示I am a receiver! #include iostream using namespace std;class Receiver { public:void show(){cout I am a receiver!endl;} };class Transimiter { public:Receiver * p_receiver; };int main() {Transimiter t1;Receiver r1;t1.p_receiverr1;t1.p_receiver-show();return 0; } 步骤二 不能把所有的事情都让类的成员函数去处理因为没有人知道未来会添加哪些功能所以把接收者中定义的show函数改成一个函数指针会更合理。这样可以在接收者初始化对象的时候赋予具体的函数地址完成具体的功能。运行结果 I am a slot_show function! I am a slot_print function! #include iostream using namespace std;class Receiver { public:void (*fun)();//函数指针Receiver(void (*pfun)()){this-funpfun;//函数指针初始化} };void slot_show() {coutI am a slot_show function!endl; } void slot_print() {coutI am a slot_print function!endl; }class Transimiter { public:Receiver * p_receiver; };int main() {Transimiter t1;Receiver r1(slot_show);//定义两个不同的接收者对象Receiver r2(slot_print);t1.p_receiverr1;t1.p_receiver-fun();t1.p_receiverr2;t1.p_receiver-fun();return 0; }步骤三 为了解决一个发送者对象和多个接收者对象产生关系的问题发送者对象应该用一个指针数组保存所有的接收者我的数组大小为2。程序的运行结果和上面一样。 #include iostream using namespace std;class Receiver { public:void (*fun)();//函数指针Receiver(void (*pfun)()){this-funpfun;//函数指针初始化} };void slot_show() {coutI am a slot_show function!endl; } void slot_print() {coutI am a slot_print function!endl; }class Transimiter { public:Receiver * p_receiver[2]; };int main() {Transimiter t1;Receiver r1(slot_show);//定义两个不同的接收者对象Receiver r2(slot_print);t1.p_receiver[0]r1;t1.p_receiver[1]r2;t1.p_receiver[0]-fun();t1.p_receiver[1]-fun();return 0; } 步骤四 有关发送者对象的信号发送应当有一个专门的成员函数集中处理 所以程序做一点修正运行结果不变如下 #include iostream using namespace std;class Receiver { public:void (*fun)();//函数指针Receiver(void (*pfun)()){this-funpfun;//函数指针初始化} };void slot_show() {coutI am a slot_show function!endl; } void slot_print() {coutI am a slot_print function!endl; }class Transimiter { public:Receiver * p_receiver[2]; public:void send_message(){this-p_receiver[0]-fun();this-p_receiver[1]-fun();} };int main() {Transimiter t1;Receiver r1(slot_show);//定义两个不同的接收者对象Receiver r2(slot_print);t1.p_receiver[0]r1;t1.p_receiver[1]r2;t1.send_message();return 0; }步骤五 上面的程序发送的消息是空的我用一个整型的数字代表一个合法的消息程序稍作修改运行结果如下 I am a slot_show function! num:100 I am a slot_print function!  num:100 #include iostream using namespace std;class Receiver { public:void (*fun)(int);//函数指针Receiver(void (*pfun)(int)){this-funpfun;//函数指针初始化} };void slot_show(int num) {coutI am a slot_show function!endl;coutnum:numendl; } void slot_print(int num) {coutI am a slot_print function!endl;coutnum:numendl; }class Transimiter { public:Receiver * p_receiver[2]; public:void send_message(int num){this-p_receiver[0]-fun(num);this-p_receiver[1]-fun(num);} };int main() {Transimiter t1;Receiver r1(slot_show);//定义两个不同的接收者对象Receiver r2(slot_print);t1.p_receiver[0]r1;t1.p_receiver[1]r2;t1.send_message(100);return 0; } 步骤六 上面的程序中发送者和接收者之间建立联系的过程不够形象我用一个函数命名为管道连接管理对象之间的通信管道。安全起见同时把发送者对象里面的指针数组从公用属性改为私有属性。 #include iostream using namespace std;class Receiver { public:void (*fun)(int);//函数指针Receiver(void (*pfun)(int)){this-funpfun;//函数指针初始化} };void slot_show(int num) {coutI am a slot_show function!endl;coutnum:numendl; } void slot_print(int num) {coutI am a slot_print function!endl;coutnum:numendl; }class Transimiter { private://成员变量改为私有属性Receiver * p_receiver[2]; public:void send_message(int num){this-p_receiver[0]-fun(num);this-p_receiver[1]-fun(num);}void connect_pipe(Receiver *pR,int num)//建立管道连接{this-p_receiver[num]pR;} };int main() {Transimiter t1;Receiver r1(slot_show);//定义两个不同的接收者对象Receiver r2(slot_print);t1.connect_pipe(r1,0);t1.connect_pipe(r2,1);t1.send_message(100);return 0; } 步骤七 由于接受者的个数也是不确定的因此不能把数组写死于是我采用一个向量vector记录接收者对象的指针相关的函数或变量做一点点修改运行结果如下 I am a slot_show function! num:100 I am a slot_print function! num:100 I am a slot_print function! num:100 #include iostream #include vector using namespace std;class Receiver { public:void (*fun)(int);//函数指针Receiver(void (*pfun)(int)){this-funpfun;//函数指针初始化} };void slot_show(int num) {coutI am a slot_show function!endl;coutnum:numendl; } void slot_print(int num) {coutI am a slot_print function!endl;coutnum:numendl; }class Transimiter { private://成员变量改为私有属性vector Receiver* receiver_v; public:void send_message(int num){for(vector Receiver*::iterator itreceiver_v.begin();it!receiver_v.end();it)//遍历器{(*it)-fun(num);//(*it)为实际的元素值}}void connect_pipe(Receiver *pR)//建立管道连接{this-receiver_v.push_back(pR);} };int main() {Transimiter t1;Receiver r1(slot_show);//定义两个不同的接收者对象Receiver r2(slot_print);Receiver r3(slot_print);t1.connect_pipe(r1);t1.connect_pipe(r2);t1.connect_pipe(r3);t1.send_message(100);return 0; }步骤八 添加一个断开连接的函数修改代码如下 #include iostream #include vector using namespace std;class Receiver { public:void (*fun)(int);//函数指针Receiver(void (*pfun)(int)){this-funpfun;//函数指针初始化} };void slot_show(int num) {coutI am a slot_show function!endl;coutnum:numendl; } void slot_print(int num) {coutI am a slot_print function!endl;coutnum:numendl; }class Transimiter { private://成员变量改为私有属性vector Receiver* receiver_v; public:void send_message(int num){for(vector Receiver*::iterator itreceiver_v.begin();it!receiver_v.end();it)//遍历器{(*it)-fun(num);//(*it)为实际的元素值}}void connect_pipe(Receiver *pR)//建立管道连接{this-receiver_v.push_back(pR);}void disconnect_pipe(Receiver *pR){for(vector Receiver*::iterator itreceiver_v.begin();it!receiver_v.end();it)//遍历器{if((*it)pR){this-receiver_v.erase(it);}}} };int main() {Transimiter t1;Receiver r1(slot_show);//定义两个不同的接收者对象Receiver r2(slot_print);Receiver r3(slot_print);t1.connect_pipe(r1);t1.connect_pipe(r2);t1.connect_pipe(r3);t1.send_message(100);t1.disconnect_pipe(r1);t1.disconnect_pipe(r2);t1.send_message(100);return 0; }