《Qt学习笔记》第一章--登录界面设计

本次的程序目的是编写一个登陆界面程序，包含了账号密码确认的功能，输入框设置提示字符，密码框采用password模式，设置登录按钮为默认焦点。基本逻辑为：当输入账户密码时，按回车键或者点击登录按钮，程序判断账号密码是否正确，若正确则弹出主窗口，否则弹出警告框。程序效果如图：

头文件：

#ifndef LOGINDIALOG_H#define LOGINDIALOG_H#include <QDialog>#include<QMessageBox>namespace Ui {class LoginDialog;}class LoginDialog : public QDialog{    Q_OBJECTpublic:    explicit LoginDialog(QWidget *parent = 0);    ~LoginDialog();private slots:    void on_enter_pushButton_clicked();private:    Ui::LoginDialog *ui;};#endif // LOGINDIALOG_H

cpp文件

#include "LoginDialog.h"#include "ui_LoginDialog.h"LoginDialog::LoginDialog(QWidget *parent) :    QDialog(parent),    ui(new Ui::LoginDialog){    ui->setupUi(this);    ui->enter_pushButton->setDefault(true);    connect(ui->enter_pushButton,&QPushButton::clicked,this,&LoginDialog::on_enter_pushButton_clicked);    connect(ui->quit_pushButton,&QPushButton::clicked,this,&LoginDialog::close);}LoginDialog::~LoginDialog(){    delete ui;}void LoginDialog::on_enter_pushButton_clicked(){    if(ui->user_lineEdit->text() == tr("wangcong") && ui->password_lineEdit->text() == tr("lovefzj"))    {        accept();    }    else    {        QMessageBox::warning(this,tr("警告"),tr("用户名或密码错误"));        ui->user_lineEdit->clear();        ui->password_lineEdit->clear();        ui->user_lineEdit->setFocus();    }}

main函数：

#include "mainwindow.h"#include"LoginDialog.h"#include <QApplication>#include<QDebug>#include<QString>int main(int argc, char *argv[]){    QApplication a(argc, argv);    MainWindow w;    LoginDialog enterWindow;    if(enterWindow.exec() == QDialog::Accepted)    {        w.show();        return a.exec();    }    else        return 0;}