Qt之消息对话框

widget.h:

#ifndef WIDGET_H
#define WIDGET_H

#include <QWidget>
#include<QLineEdit>
class Widget : public QWidget
{
    Q_OBJECT

public:
    Widget(QWidget *parent = 0);
    ~Widget();
public slots:
    void Jiemian_buju_Init();
    void showdanger();
    void showinform();
    void showquestion();
private:
    QLineEdit * qLedit1;
    QLineEdit* qLedit2;
};

#endif // WIDGET_H

widget.cpp:

#include "widget.h"
#include<QMessageBox>
#include<QPushButton>
#include<QVBoxLayout>
#include<QLineEdit>
#include<QGridLayout>
#include<QLabel>
#include<QDebug>
Widget::Widget(QWidget *parent):QWidget(parent)
{
    Jiemian_buju_Init();
}
Widget::~Widget()
{

}
void  Widget::Jiemian_buju_Init()
{
    QGridLayout *qg=new QGridLayout(this);

    QLabel *qL1=new QLabel("用户名:");
    QLabel *qL2=new QLabel("密码:");

qLedit1=new QLineEdit;
qLedit2=new QLineEdit;

qLedit2->setEchoMode(QLineEdit::Password);

    QPushButton *qb1=new QPushButton("确认:");
    QPushButton *qb2=new QPushButton("取消:");
    qg->addWidget(qL1,0,0,1,1);
    qg->addWidget(qL2,1,0,1,1);
    qg->addWidget(qLedit1,0,1,1,1);
    qg->addWidget(qLedit2,1,1,1,1);

    qg->addWidget(qb1,2,0,1,1);
    qg->addWidget(qb2,2,1,1,1);

    this->setLayout(qg);

   connect(qb1,SIGNAL(clicked()),this,SLOT(showdanger()));
   connect(qb2,SIGNAL(clicked()),this,SLOT(showquestion()));

}
void Widget::showdanger()
{
   if((qLedit1->text()=="admin")&&(qLedit2->text()=="123456"))
   {
            showinform();
   }
   else {
       QMessageBox::warning(this,"warning","密码错误,登录失败!");
   }

}
void Widget::showinform()
{
QMessageBox::information(this,"information","登录成功!");
}
void Widget::showquestion()
{
      int s=QMessageBox::question(this,"question","确认退出吗?",QMessageBox::Open|QMessageBox::Save);
      qDebug()<<s<<endl;
   if(s==2048)
   {
       close();
   }

}

main.cpp:

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

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

    return a.exec();
}

效果图: