如何使用已转换的参数值连接信号和插槽

Question

使用已转换的参数值连接信号和插槽的任何简单方法。例如，我有一个signal(bool state)，它连接到一个插槽slot(bool reversed_state)，这里状态是信号状态的反转状态（逻辑上不是）。

Answer 1

创建一个中间插槽来链接两者： -

class MyClass : public QObject
{
    Q_OBJECT
public:
    signals:
        void SomeSignal(bool state);
        void SomeSignalSwitched(bool state); // reverse the state

    public slots:            

        void ReversedStateSlot(bool reversed_state);
 };


void MyClass::SomeSignalSwitched(bool state)
{
    bool newState = !state
    emit SomeSignalSwitched(newState);
}

// NOTE Qt 5 connect functions

connect(myClassObject, &MyClass::SomeSignal, myClassObject, &MyClass::SomeSignalSwitched);
connect(myClassObject, &MyClass::SomeSignalSwitched, myClassObject, &MyClass::ReversedStateSlot);