Qt 模仿 Android滑动窗口效果

#include "widget.h" #include "ui_widget.h" Widget::Widget(QWidget *parent) : QWidget(parent), ui(new Ui::Widget) { ui->setupUi(this); m_scrollBarV = ui->tableWidget->verticalScrollBar(); QObjectList objectList = ui->tableWidget->children(); for(int i = 0; i < objectList.count(); i++) { if(objectList.at(i)->objectName() == "qt_scrollarea_viewport") { objectList.at(i)->installEventFilter(this); } } } Widget::~Widget() { delete ui; } bool Widget::eventFilter(QObject *obj, QEvent *event) { static int press_y = 0; static int move_y = -1; static int release_y = 0; static QDateTime pressDateTime; static QPropertyAnimation *animation = new QPropertyAnimation(); if("qt_scrollarea_viewport" != obj->objectName()) { return false; } int scrollV_max = m_scrollBarV->maximum (); int scrollV_min = m_scrollBarV->minimum (); //根据鼠标的动作——按下、放开、拖动，执行相应的操作 if(event->type() == QEvent::MouseButtonPress) { //记录按下的时间、坐标 pressDateTime = QDateTime::currentDateTime(); move_y = QCursor::pos().y(); press_y = move_y; animation->stop(); } else if(event->type() == QEvent::MouseButtonRelease) { //鼠标放开，根据鼠标拖动的垂直距离和持续时间，设置窗口滚动快慢程度和距离 if(animation->targetObject() != m_scrollBarV) { animation->setTargetObject(m_scrollBarV); animation->setPropertyName("value"); } move_y = -1; release_y = QCursor::pos().y(); // qDebug()<<"MouseButtonRelease QCursor::pos().y()="<<QCursor::pos().y(); QObject *parent_obj = obj->parent(); if(parent_obj != 0 || parent_obj->inherits("QAbstractItemView")) { QTimer::singleShot(150, (QAbstractItemView *)parent_obj , SLOT(clearSelection())); } int endValue; int pageStep; if(release_y - press_y != 0 && qAbs(release_y - press_y) > 45) { //qDebug()<<"obj->objectName()="<<obj->objectName(); int mseconds = pressDateTime.msecsTo(QDateTime::currentDateTime()); // qDebug()<<"mseconds="<<mseconds; int limit = 440; pageStep = 240;//scrollBarV->pageStep(); // qDebug()<<"pageStep="<<pageStep; if(mseconds > limit)//滑动的时间大于某个值的时候，不再滚动(通过增加分母) { mseconds = mseconds + (mseconds - limit) * 20; } if(release_y - press_y > 0) { endValue = m_scrollBarV->value() - pageStep * (200.0 / mseconds);//.0避免避免强制转换为整形 if(scrollV_min > endValue) { endValue = scrollV_min; } } else if(release_y - press_y < 0) { endValue = m_scrollBarV->value() + pageStep * (200.0 / mseconds); if(endValue > scrollV_max) { endValue = scrollV_max; } } if(mseconds > limit) { mseconds = 0;//滑动的时间大于某个值的时候，滚动距离变小，减小滑动的时间 } animation->setDuration(mseconds+550); animation->setEndValue(endValue); animation->setEasingCurve(QEasingCurve::OutQuad); animation->start(); return true; } } else if(event->type() == QEvent::MouseMove && move_y >= 0) { //窗口跟着鼠标移动 int move_distance = QCursor::pos().y() - move_y; int endValue = m_scrollBarV->value() - move_distance; if(scrollV_min > endValue) { endValue = scrollV_min; } if(endValue > scrollV_max) { endValue = scrollV_max; } m_scrollBarV->setValue(endValue); //qDebug()<<"endValue="<<endValue; //qDebug()<<"move_distance="<<move_distance; move_y = QCursor::pos().y(); } return false; }