Qt 实现鼠标拖动控件
作者:互联网
在QT项目中,窗口设置 setWindowFlags(Qt::FramelessWindowHint) 之后,就无法拖动;所以会自定义一个menubar控件,并实现窗口拖动;
效果如上图,上代码:
#include <QMainWindow>
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
MainWindow(QWidget *parent = 0);
~MainWindow();
protected:
bool eventFilter(QObject *, QEvent *);
private:
QWidget *m_menu;
};
cpp:
#include "mainwindow.h"
#include <QMouseEvent>
MainWindow::MainWindow(QWidget *parent)
: QMainWindow(parent)
{
setWindowFlags(Qt::FramelessWindowHint);
this->setFixedSize(500,300);
m_menu = new QWidget(this);
m_menu->setFixedSize(this->width(), 50);
m_menu->setStyleSheet("background-color:lightblue;");
m_menu->installEventFilter(this);
}
MainWindow::~MainWindow()
{
}
bool MainWindow::eventFilter(QObject *watched, QEvent *eve)
{
static QPoint mousePoint;
static bool mousePressed = false;
QMouseEvent *event = static_cast<QMouseEvent *>(eve);
if(watched == m_menu)
{
if(event->type() == QEvent::MouseButtonPress)
{
if(event->button() == Qt::LeftButton)
{
mousePressed = true;
mousePoint = event->globalPos() - this->pos();
return true;
}
}
else if(event->type() == QEvent::MouseButtonRelease)
{
mousePressed = false;
return true;
}
else if(event->type() == QEvent::MouseMove)
{
this->move(event->globalPos() - mousePoint);
return true;
}
}
return QWidget::eventFilter(watched, eve);
}
两点注意:
1.m_menu->installEventFilter(this);
本代码中,需要拖动的控件是自定义的m_menu,注册监测对象;
2.eventFilter;
在这个事件中,处理目标对象的事件;所以代码中先判断 (watched == m_menu);
原创,转载请注明出处;
标签:控件,QEvent,return,Qt,拖动,menu,MainWindow,QWidget,event 来源: https://blog.csdn.net/gz9456/article/details/110228988