在 Qt 中的 show() 上更改窗口位置

Question

我知道当我从当前 window( ) 创建窗口对象时重新定位窗口的过程，currWindow如下所示：

QDesktopWidget widget;
QRect screenGeometry = widget.screenGeometry();
int height = screenGeometry.height();
int width = screenGeometry.width();
//set to middle of screen
targetwindow->move((width - targetwindow->width()) / 2.0,
                (height - targetwindow->height()) / 2.0);
targetwindow->show();

currWindow我也有类似的代码。不过，我有一个后退按钮，其中targetwindow隐藏了targetwindow和。我使用信号槽机制实现了这一点，如下所示：show()currWindow

connect(targetwindow,&TargetWindow::pressTargetWindowGoBackButton,
                                           this,&CurrentWindow::show);

问题是在按下节目上的后退按钮后targetwindow，currWindow但没有保持我之前设置的位置（即屏幕中间）。我尝试通过添加代码来使用此运算符将其定位在绘制事件中来纠正它，但它不起作用：

void currWindow::paintEvent(QPaintEvent *pe)
{

        QDesktopWidget widget;
        QRect screenGeometry = widget.screenGeometry();
        int height = screenGeometry.height();
        int width = screenGeometry.width();
        this->move((width - this->width()) / 2.0,
                        (height - this->height()) / 2.0);
}

我该怎么做呢？我是否需要重写预定义的 show() 函数以及如何重写？

编辑：添加我的项目的代码。这里 currentwindow -> MainWindow 和 targetwindow->Dialog。

对话框.h

#ifndef DIALOG_H
#define DIALOG_H

#include <QDialog>

namespace Ui {
class Dialog;
}

class Dialog : public QDialog
{
    Q_OBJECT

signals:
    void goBack();
public:
    explicit Dialog(QWidget *parent = 0);
    ~Dialog();

private slots:
    void on_pushButton_clicked();

private:
    Ui::Dialog *ui;
};

#endif // DIALOG_H

主窗口.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include "dialog.h"
namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();

private slots:
    void on_pushButton_clicked();

private:
    Ui::MainWindow *ui;
    Dialog *dia;
};

#endif // MAINWINDOW_H

主程序

#include "mainwindow.h"
#include <QApplication>
#include <QDesktopWidget>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;

    QDesktopWidget widget;
    QRect screenGeometry = widget.screenGeometry();//.availableGeometry(widget.primaryScreen());

    int height = screenGeometry.height();
    int width = screenGeometry.width();
    w.move(-50000,-50000);

    w.move((width - w.width()) / 2.0,
                    (height - w.height()) / 2.0);
    w.show();
    return a.exec();
}

主窗口.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QDesktopWidget>


MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    dia=new Dialog;
    connect(dia,&Dialog::goBack,this,&MainWindow::show);
}

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

void MainWindow::on_pushButton_clicked()
{

    QDesktopWidget widget;
    QRect screenGeometry = widget.screenGeometry();//.availableGeometry(widget.primaryScreen());

    int height = screenGeometry.height();
    int width = screenGeometry.width();
    dia->move(-50000,-50000);
//    dia->show();
    dia->move((width - dia->width()) / 2.0,
                    (height - dia->height()) / 2.0);
    dia->show();
    hide();
}

对话框.cpp

#include "dialog.h"
#include "ui_dialog.h"

Dialog::Dialog(QWidget *parent) :
    QDialog(parent),
    ui(new Ui::Dialog)
{
    ui->setupUi(this);
}

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

void Dialog::on_pushButton_clicked()
{
    emit goBack();
    hide();
}

主窗口.ui

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>MainWindow</class>
 <widget class="QMainWindow" name="MainWindow">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>900</width>
    <height>600</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>MainWindow</string>
  </property>
  <widget class="QWidget" name="centralWidget">
   <widget class="QPushButton" name="pushButton">
    <property name="geometry">
     <rect>
      <x>150</x>
      <y>90</y>
      <width>201</width>
      <height>141</height>
     </rect>
    </property>
    <property name="text">
     <string>OK</string>
    </property>
   </widget>
  </widget>
  <widget class="QMenuBar" name="menuBar">
   <property name="geometry">
    <rect>
     <x>0</x>
     <y>0</y>
     <width>900</width>
     <height>19</height>
    </rect>
   </property>
  </widget>
  <widget class="QToolBar" name="mainToolBar">
   <attribute name="toolBarArea">
    <enum>TopToolBarArea</enum>
   </attribute>
   <attribute name="toolBarBreak">
    <bool>false</bool>
   </attribute>
  </widget>
  <widget class="QStatusBar" name="statusBar"/>
 </widget>
 <layoutdefault spacing="6" margin="11"/>
 <resources/>
 <connections/>
</ui>

对话框.ui

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>Dialog</class>
 <widget class="QDialog" name="Dialog">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>900</width>
    <height>600</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>Dialog</string>
  </property>
  <widget class="QPushButton" name="pushButton">
   <property name="geometry">
    <rect>
     <x>370</x>
     <y>120</y>
     <width>231</width>
     <height>151</height>
    </rect>
   </property>
   <property name="text">
    <string>BACK</string>
   </property>
  </widget>
 </widget>
 <resources/>
 <connections/>
</ui>

如果您继续执行“确定”->“返回”->“确定”循环，您会发现主窗口不断向上移动。

Answer 1

您是否尝试过 targetwindow 的 setGeometry() 函数：

int height = screenGeometry.height();
int width = screenGeometry.width();
int x=(width - w.width()) / 2.0;
int y=(height - w.height()) / 2.0;
w.setGeometry(x,y,w.width(),w.height());
w.show();