3.QT逻辑交互（信号槽）

信号槽

1.一个信号可以连接一个槽

connect(sender, SIGNAL(signal()), receiver, SLOT(slot()));

2.一个信号可以连接多个槽

connect(sender, SIGNAL(signal()), receiver, SLOT(slot1());
connect(sender, SIGNAL(signal()), receiver, SLOT(slot2());

3.多个信号可以连接同一个槽

connect(sender1,SIGNAL(clicked()),receiver,SLOT(slot()));
connect(sender2,SIGNAL(clicked()),receiver,SLOT(slot()));
connect(sender3,SIGNAL(clicked()),receiver,SLOT(slot()));

4.一个信号可以连接另外一个信号（sender被点击时，receiver也会被点击）

connect(sender, SIGNAL(clicked(int)), receiver, SIGNAL(clicked(int));