Qt中的长按事件

Question

我想知道是否有长按新闻事件可用Qt
我正在处理的模块需要长时间按下。我看到在C7中长时间按下卸载程序

按钮单击事件和按钮按下事件给出了相同的结果吧？

alfah

Answer 1

你可以看看Qt的gesture framework，
你是后手势将是QTapAndHoldGesture然后我想。

Answer 2

您可以使用

keyPressEvent (QKeyEvent * event) 

和

keyReleaseEvent (QKeyEvent * event) 

的手柄long_press_event

Answer 3

的快速，容易和老式方式，如果你不想使用该手势的东西去有点像这样：

在头声明毫秒时间戳保持上次按下的时间。

private: 
    // Remembers the point in time when mouse button went down 
    quint64 mLastPressTime=0; 
    // Pressing and holding for one full second constitutes a "longpress", set whatever value in milliseconds you want here. 
    static const quint64 MY_LONG_PRESS_THRESHOLD=1000; 
protected: 
    // Declare that we are overriding QWidget's events for mouse press and release 
    void mousePressEvent(QMouseEvent *) Q_DECL_OVERRIDE; 
    void mouseReleaseEvent(QMouseEvent *) Q_DECL_OVERRIDE; 
signals: 
    // Our custom signal to emit once a longpress is detected. 
    void longPressEvent(QMouseEvent *); 

在源定义鼠标按下并释放处理器，像这样：

void MyClass::mousePressEvent(QMouseEvent *event) 
{ 
    // Remeber last time mousr was pressed 
    mLastPressTime=QDateTime::currentMSecsSinceEpoch(); 
} 

void MyClass::mouseReleaseEvent(QMouseEvent *event) 
{ 
    // Calculate for how long the button has been pressed upon release 
    const quint64 pressTime = QDateTime::currentMSecsSinceEpoch() - mLastPressTime; 
    // The press time exceeds our "threshold" and this constitutes a longpress 
    if(pressTime > MY_LONG_PRESS_THRESHOLD){ 
     // We pass the original mouse event in case it is useful (it contains all sorts of goodies like mouse posittion, which button was pressed etc). 
     emit longPressEvent(event); 
    } 
} 

注：我没有编译这段代码，除了内置的编译器在我的脑海里面有很多非传统扩展。