Qt 延迟刷新View的技巧

#include <QTreeView>

class RoomTreeWidget : public QTreeView

{

Q_OBJECT

public:

RoomTreeWidget(QWidget *parent = 0);

~RoomTreeWidget();

void setVScrollDelayUpdateTime(quint32 mesc);

protected:

void timerEvent(QTimerEvent *event);

private:

quint32 vScrollDelayUpdateMesc;

int vScrollDelayUpdateTimerId;

};

#endif // ROOMLISTWIDGET_H

#include "roomtreewidget.h"

#include <QScrollBar>

#include <QTimerEvent>

RoomTreeWidget::RoomTreeWidget(QWidget *parent)

    : QTreeView(parent), vScrollDelayUpdateMesc(0), vScrollDelayUpdateTimerId(0)

{

    setUniformRowHeights(true);

}

RoomTreeWidget::~RoomTreeWidget()

{

}

void RoomTreeWidget::setVScrollDelayUpdateTime(quint32 mesc)

{

    if (vScrollDelayUpdateMesc == mesc)

    {

        return;

    }

    vScrollDelayUpdateMesc = mesc;

    QScrollBar *vScrollBar = verticalScrollBar();

    if (vScrollBar)

    {

        if (vScrollDelayUpdateMesc > 0)

        {

            vScrollBar->setTracking(false);

            if (vScrollDelayUpdateTimerId != 0)

            {

                killTimer(vScrollDelayUpdateTimerId);

            }

            vScrollDelayUpdateTimerId = startTimer(vScrollDelayUpdateMesc);

        }

else

        {

            vScrollBar->setTracking(true);

            if (vScrollDelayUpdateTimerId != 0)

            {

                killTimer(vScrollDelayUpdateTimerId);

                vScrollDelayUpdateTimerId = 0;

            }

        }

    }

}

void RoomTreeWidget::timerEvent(QTimerEvent *event)

{

    QTreeView::timerEvent(event);

    if (event->timerId() == vScrollDelayUpdateTimerId)

    {

        QScrollBar *vScrollBar = verticalScrollBar();

        if (vScrollBar)

        {

            vScrollBar->triggerAction(QSlider::SliderMove);

        }

    }

}