一.登录对话框需求分析

二.代码实现

 main.c：

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

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

Widget.h：

#ifndef _WIDGET_H_
#define _WIDGET_H_

#include <QtGui/QWidget>
#include <QPushButton>

class Widget : public QWidget
{
    Q_OBJECT
private:
    QPushButton TestBtn;
private slots:
    void TestBtn_Clicked();
public:
    Widget(QWidget *parent = 0);
    ~Widget();
};

#endif

Widget.cpp：

#include "Widget.h"
#include "QLoginDialog.h"

#include <QDebug>

Widget::Widget(QWidget *parent) : QWidget(parent), TestBtn(this)
{
    TestBtn.setText("Test Login Dialog");

    setFixedSize(200, 50);

    connect(&TestBtn, SIGNAL(clicked()), this, SLOT(TestBtn_Clicked()));
}

void Widget::TestBtn_Clicked()
{
    QLoginDialog dlg;

    if( dlg.exec() == QDialog::Accepted )
    {
        qDebug() << "User: " + dlg.getUser();
        qDebug() << "Pwd: " + dlg.getPwd();
    }
}

Widget::~Widget()
{
    
}

QLoginDialog.h :

#ifndef _QLOGINDIALOG_H_
#define _QLOGINDIALOG_H_

#include <QtGui/QDialog>
#include <QLabel>
#include <QLineEdit>
#include <QPushButton>

class QLoginDialog : public QDialog
{
    Q_OBJECT
private:
    QLabel UserLabel;
    QLabel PwdLabel;
    QLineEdit UserEdit;
    QLineEdit PwdEdit;
    QPushButton LoginBtn;
    QPushButton CancelBtn;
    QString m_user;
    QString m_pwd;
private slots:
    void LoginBtn_Clicked();
    void CancelBtn_Clicked();
public:
    QLoginDialog(QWidget *parent = 0);
    QString getUser();
    QString getPwd();
    ~QLoginDialog();
};


#endif

QLoginDialog.c:

#include "QLoginDialog.h"

#include <QDebug>

QLoginDialog::QLoginDialog(QWidget* parent) : QDialog(parent, Qt::WindowCloseButtonHint),
    UserLabel(this), PwdLabel(this), UserEdit(this), PwdEdit(this), LoginBtn(this), CancelBtn(this)
{
    UserLabel.setText("User ID:");
    UserLabel.move(20, 30);
    UserLabel.resize(60, 25);

    UserEdit.move(85, 30);
    UserEdit.resize(180, 25);

    PwdLabel.setText("Password:");
    PwdLabel.move(20, 65);
    PwdLabel.resize(60,25);

    PwdEdit.move(85, 65);
    PwdEdit.resize(180, 25);
    PwdEdit.setEchoMode(QLineEdit::Password);

    CancelBtn.setText("Cancel");
    CancelBtn.move(85, 110);
    CancelBtn.resize(85, 30);

    LoginBtn.setText("Login");
    LoginBtn.move(180, 110);
    LoginBtn.resize(85, 30);

    setWindowTitle("Login");
    setFixedSize(285, 170);

    connect(&LoginBtn, SIGNAL(clicked()), this, SLOT(LoginBtn_Clicked()));
    connect(&CancelBtn, SIGNAL(clicked()), this, SLOT(CancelBtn_Clicked()));
}

void QLoginDialog::LoginBtn_Clicked()
{
    qDebug() << "LoginBtn_Clicked() Begin";

    m_user = UserEdit.text().trimmed();
    m_pwd = PwdEdit.text();

    done(Accepted);

    qDebug() << "LoginBtn_Clicked() End";
}

void QLoginDialog::CancelBtn_Clicked()
{
    qDebug() << "CancelBtn_Clicked() Begin";

    done(Rejected);

    qDebug() << "CancelBtn_Clicked() End";
}

QString QLoginDialog::getUser()
{
    return m_user;
}

QString QLoginDialog::getPwd()
{
    return m_pwd;
}

QLoginDialog::~QLoginDialog()
{

}

运行结果：