启动QPropertyAnimation延迟

Question

当鼠标悬停父部件时，我有一个显示/隐藏框架的小动画(在“MyWidget”下面的代码片段中)。

动画简单地改变了框架的maximumWidth属性，使框架成为可见的某种“幻灯片效果”。(框架本身位于网格布局中。)

我的问题是如何启动动画延迟？示例:在鼠标leaveEvent之后启动500 is，因此滑出效果被延迟，并且没有立即启动.。

void MyWidget::enterEvent( QEvent * event )
{
    //slide-in effect
    QPropertyAnimation *animation = new QPropertyAnimation(ui.frame_buttons, "maximumWidth");
    animation->setDuration(1000);
    animation->setStartValue(ui.frame_buttons->maximumWidth());
    animation->setEndValue(100);
    animation->setEasingCurve(QEasingCurve::InOutQuad);

    animation->start();
}

void MyWidget::leaveEvent( QEvent * event )
{
    //slide-out effect
    QPropertyAnimation *animation = new QPropertyAnimation(ui.frame_buttons, "maximumWidth");
    animation->setDuration(1000);
    animation->setStartValue( ui.frame_buttons->maximumWidth() );
    animation->setEndValue(0);
    animation->setEasingCurve(QEasingCurve::InOutQuad);

    //delay start() for a small amount of time
    animation->start();
}

Answer 1

来自Mezzo的暗示--再次感谢！--但是我插入了一个跳棋，以避免“闪烁效应”。(当slideOut效果仍在运行时，总是等待静态毫秒会导致异步slideIn效果。)

可能对谁感兴趣的答案。(我还修复了一个内存漏洞，以避免在每个动画触发器中分配)：

void MyWidget::enterEvent( QEvent * event )
{
    //start from where the slideOut animation currently is
    m_slideInAnimation->setStartValue(ui.frame_buttons->maximumWidth());
    m_slideInAnimation->start();
}

void MyWidget::leaveEvent( QEvent * event )
{
    //start from where the slideIn animation currently is
    m_slideOutAnimation->setStartValue( ui.frame_buttons->maximumWidth() );

    //start slide_out animation only if slide_in animation finish to avoid flicker effect
    if(ui.frame_buttons->maximumWidth() != m_slideInAnimation->endValue()) 
    {
        m_slideOutAnimation->start();
    }
    else
    {
        QTimer::singleShot(700, m_slideOutAnimation, SLOT(start()));
    }   
}

void MyWidget::createAnimations()
{
    m_slideInAnimation= new QPropertyAnimation(ui.frame_buttons, "maximumWidth");
    m_slideInAnimation->setDuration(1000);
    m_slideInAnimation->setEndValue(100);
    m_slideInAnimation->setEasingCurve(QEasingCurve::InOutQuad);

    m_slideOutAnimation = new QPropertyAnimation(ui.frame_buttons, "maximumWidth");
    m_slideOutAnimation->setDuration(1000);
    m_slideOutAnimation->setEndValue(0);
    m_slideOutAnimation->setEasingCurve(QEasingCurve::InOutQuad);
}

void MyWidget::MyWidget()
{
    this->createAnimations();
}

void MyWidget::~MyWidget()
{
    delete m_slideInAnimation;
    delete m_slideOutAnimation;
}