QT 初试 MainWindow简易窗体

1.创建一个空的QT工程文件

2 建立程序文件

MainWindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include<QMainWindow>

class MainWindow : public QMainWindow{
    Q_OBJECT
public:
    MainWindow();
};

#endif // MAINWINDOW_H

MainWindow.cpp

#include<QtGui>
#include"MainWindow.h"

MainWindow::MainWindow(){
    QWidget *widget=new QWidget;
    setCentralWidget(widget);

    QWidget *topfiller=new QWidget;
    topfiller->setSizePolicy(QSizePolicy::Expanding,QSizePolicy::Expanding);

    QWidget *bottomFiller=new QWidget;
    bottomFiller->setSizePolicy(QSizePolicy::Expanding,QSizePolicy::Expanding);

    QVBoxLayout *layout=new QVBoxLayout;
    layout->addWidget(topfiller);
    layout->addWidget(bottomFiller);
    widget->setLayout(layout);

    setWindowTitle(tr("Main Window"));
    resize(512,480);

}

Main.cpp

#include<QApplication>
#include"MainWindow.h"

int main(int argc,char* argv[]){
    QApplication app(argc,argv);
    MainWindow wnd;
    wnd.show();
    app.exec();

}