<Qt C++>显示坐标 显示对话框内容

#ifndef MAINWINDOW_H#define MAINWINDOW_H#include namespace Ui{class MainWindow;}class MainWindow : public QMainWindow{    Q_OBJECTpublic:    explicit MainWindow(QWidget *parent = 0);    ~MainWindow();private slots:    void ButtonSlot();protected:    void paintEvent(QPaintEvent *event);        void mousePressEvent(QMouseEvent *event);private:    Ui::MainWindow *ui;    QString str;};#endif // MAINWINDOW_H#include "mainwindow.h"#include "ui_mainwindow.h"#include#include #include #include MainWindow::MainWindow(QWidget *parent) :    QMainWindow(parent),    ui(new Ui::MainWindow){    ui->setupUi(this);        QObject::connect(ui->pushButton,SIGNAL(clicked()),this,SLOT(ButtonSlot()));//连接信号和槽}MainWindow::~MainWindow()//析构函数{    delete ui;}void MainWindow::ButtonSlot(){ str=ui->lineEdit->text(); ui->textBrowser->setText(str);}//把lineEdit内容放到Browservoid MainWindow::paintEvent(QPaintEvent *event){ Q_UNUSED(event);    QPainter painter(this);     painter.drawText(170,75,"坐标-》" );}//用painter随便写点啥void MainWindow::mousePressEvent(QMouseEvent *event){ ui->label->setText(QString("
(%1, %2)
") .arg(QString::number(event->x()), QString::number(event->y())));}//坐标显示到label#include "mainwindow.h"#include int main(int argc, char *argv[]){    QApplication a(argc, argv);    MainWindow w;    w.show();    return a.exec();}

上传个图真麻烦