Qt widget 鼠标拖拽,分离新窗口

环境

Qt 5.4.2

功能

鼠标拖拽widget,分离出新的窗口,鼠标关闭窗口后,widget恢复之前的位置

源码

1.mainWindow.h

class MainWindow : public QMainWindow
{
private:
    QWidget *ObjWidget;

    QWidget *Widget1;
    QWidget *Widget2;
    QWidget *Widget3;
    QWidget *Widget4;
    QWidget *Widget5;
    QWidget *Widget6;

    QLayout *Layout1;
    QLayout *Layout2;
    QLayout *Layout3;
    QLayout *Layout4;
    QLayout *Layout5;
    QLayout *Layout6;

private slots:
    bool eventFilter(QObject *object, QEvent *event);
public:
    void MovePosWidget(QWidget *widget, QEvent *event);
    void RecoverWidget(QWidget *widget);
    void DeleteLayout(QWidget *widget);
    void DisplayWidget(QWidget *widget, QEvent *event);
};

2.mainWindow.cpp

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);

    ui->widget1->installEventFilter(this);
    ui->widget2->installEventFilter(this);
    ui->widget3->installEventFilter(this);
    ui->widget4->installEventFilter(this);
    ui->widget5->installEventFilter(this);
    ui->widget6->installEventFilter(this);

}

MainWindow::~MainWindow()
{
    delete ui;
}


static QPoint lastPoint;
static bool isHover = false;
static bool isHiden = false;

bool MainWindow::eventFilter(QObject *object, QEvent *event)
{
    ObjWidget = NULL;
    ObjWidget = qobject_cast<QWidget*>(object);

    //筛选出Widget
    if(ObjWidget == NULL) { return QMainWindow::eventFilter(object,event); }


    switch(event->type())
    {
       //鼠标按下事件
       case QEvent::MouseButtonPress:{

          QMouseEvent* mouseEvent  = static_cast<QMouseEvent*>(event);

          if(ObjWidget->rect().contains(mouseEvent->pos()) && (mouseEvent->button() == Qt::LeftButton))
          {
               lastPoint = mouseEvent->pos();
               isHover = true;
          }

       }break;
       //鼠标移动
       case QEvent::MouseMove:{

            if(!isHover)  {  break;  }

            if(NULL == ObjWidget->parent())
            {
                MovePosWidget(ObjWidget,event);   //Widget窗口随鼠标移动
                return QMainWindow::eventFilter(ObjWidget,event);
            }


            DeleteLayout(ObjWidget);             //删除布局
            DisplayWidget(ObjWidget,event);      //显示窗口


       }break;
       //鼠标释放
       case QEvent::MouseButtonRelease:{

           if(!isHover)  {  break;  }

           if(NULL == ObjWidget->parent()) { return QMainWindow::eventFilter(ObjWidget,event); }

           isHover = false;

       }break;
       case QEvent::Close:{

           RecoverWidget(ObjWidget);            //恢复显示
           isHiden = true;

       }break;
       case QEvent::Hide:{

           if(isHiden)
           {
              isHiden = false;
           }else{

              return QMainWindow::eventFilter(ObjWidget,event);
           }
       }break;
       default:break;
    }

    return false;

}



void MainWindow::DisplayWidget(QWidget *widget,QEvent *event)
{
    QMouseEvent* mouseEvent = static_cast<QMouseEvent*>(event);

    if("widget1" == widget->objectName())
    {
        Widget1 = widget;

        Widget1->setParent(NULL);
        Widget1->setWindowFlags(Qt::Dialog| Qt::WindowMinMaxButtonsHint | Qt::WindowCloseButtonHint);

        Widget1->setGeometry(mouseEvent->globalX(),mouseEvent->globalY(),300,300);
        Widget1->show();

        Widget1->move(mouseEvent->globalX(),mouseEvent->globalY());

        Widget1->setWindowTitle("Widget1");
        //......
    }

}

void MainWindow::DeleteLayout(QWidget *widget)
{

    if(("widget1" == widget->objectName()) && (NULL != ui->widget1_back->layout()))
    {
        Layout1 =  ui->widget1_back->layout();

        while(ui->widget1_back->layout()->count() > 0)
        {
            QLayoutItem *item = ui->widget1_back->layout()->takeAt(0);
            delete item;
        }
        ui->widget1_back->setMaximumWidth(0);
    }
    //......
}

void MainWindow::RecoverWidget(QWidget *widget)
{
    if("widget1" == widget->objectName())
    {
        Widget1->setParent(ui->widget1_back);
        Layout1->removeWidget(Widget1);
        Layout1->addWidget(Widget1);
        Layout1->setMargin(0);

        ui->widget1_back->setLayout(Layout1);
        ui->widget1_back->setMaximumWidth(16777215);

    }
    //......
}

void MainWindow::MovePosWidget(QWidget *widget, QEvent *event)
{
    QMouseEvent* mouseEvent = static_cast<QMouseEvent*>(event);

    if("widget1" == widget->objectName())
    {
        widget->move(mouseEvent->globalX(),mouseEvent->globalY());
    }
    //......
}

运行