创建登录框

比眉伴天荒 2022-05-27 13:23 237阅读 0赞

1.创建窗口

首先，创建一个主窗口

![70][]

然后，创建登录框，需要用户输入用户名和密码

![70 1][]

两个窗口的关联就在主函数完成即可，如下：

Widget w;
        loginDlg login;
        if(login.exec() == QDialog::Accepted)
        {
            w.show();
            return a.exec();
        }

整个工程如图所示：

![70 2][]

logTest.pro代码：

#-------------------------------------------------
    #
    # Project created by QtCreator 2016-12-23T16:36:04
    #
    #-------------------------------------------------
    
    QT       += core gui
    
    greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
    
    TARGET = logTest
    TEMPLATE = app
    
    # The following define makes your compiler emit warnings if you use
    # any feature of Qt which as been marked as deprecated (the exact warnings
    # depend on your compiler). Please consult the documentation of the
    # deprecated API in order to know how to port your code away from it.
    DEFINES += QT_DEPRECATED_WARNINGS
    
    # You can also make your code fail to compile if you use deprecated APIs.
    # In order to do so, uncomment the following line.
    # You can also select to disable deprecated APIs only up to a certain version of Qt.
    #DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0
    
    
    SOURCES += main.cpp\
            widget.cpp \
        logindlg.cpp
    
    HEADERS  += widget.h \
        logindlg.h
    
    FORMS    += widget.ui \
        logindlg.ui

logindlg.h代码：

#ifndef LOGINDLG_H
    #define LOGINDLG_H
    
    #include <QDialog>
    
    namespace Ui {
    class loginDlg;
    }
    
    class loginDlg : public QDialog
    {
        Q_OBJECT
    
    public:
        explicit loginDlg(QWidget *parent = 0);
        ~loginDlg();
    
    private slots:
        void on_loginBtn_clicked();
    
    private:
        Ui::loginDlg *ui;
    };
    
    #endif // LOGINDLG_H

widget.h代码：

#ifndef WIDGET_H
    #define WIDGET_H
    
    #include <QWidget>
    
    namespace Ui {
    class Widget;
    }
    
    class Widget : public QWidget
    {
        Q_OBJECT
    
    public:
        explicit Widget(QWidget *parent = 0);
        ~Widget();
    
    private:
        Ui::Widget *ui;
    };
    
    #endif // WIDGET_H

loginDlg.cpp代码：

#include "logindlg.h"
    #include "ui_logindlg.h"
    #include <QMessageBox>
    
    loginDlg::loginDlg(QWidget *parent) :
        QDialog(parent),
        ui(new Ui::loginDlg)
    {
        ui->setupUi(this);
    }
    
    loginDlg::~loginDlg()
    {
        delete ui;
    }
    
    void loginDlg::on_loginBtn_clicked()
    {
        if(ui->userlineEdit->text()==tr("admin")&&ui->pwdlineEdit->text()==tr("123456"))
        {
            accept();
        }
        else
        {
            QMessageBox::warning(this,tr("warning"),tr("username or password error !!!"),QMessageBox::Yes);
        }
    }

main.cpp代码：

#include "widget.h"
    #include <QApplication>
    #include "logindlg.h"
    
    int main(int argc, char *argv[])
    {
        QApplication a(argc, argv);
        Widget w;
        loginDlg login;
        if(login.exec() == QDialog::Accepted)
        {
            w.show();
            return a.exec();
        }
        else
            return 0;
    }

Widget.cpp代码：

#include "widget.h"
    #include "ui_widget.h"
    
    Widget::Widget(QWidget *parent) :
        QWidget(parent),
        ui(new Ui::Widget)
    {
        ui->setupUi(this);
    }
    
    Widget::~Widget()
    {
        delete ui;
    }

logindlg.ui代码：

<?xml version="1.0" encoding="UTF-8"?>
    <ui version="4.0">
     <class>loginDlg</class>
     <widget class="QDialog" name="loginDlg">
      <property name="geometry">
       <rect>
        <x>0</x>
        <y>0</y>
        <width>400</width>
        <height>300</height>
       </rect>
      </property>
      <property name="windowTitle">
       <string>Dialog</string>
      </property>
      <widget class="QLineEdit" name="userlineEdit">
       <property name="geometry">
        <rect>
         <x>170</x>
         <y>80</y>
         <width>113</width>
         <height>20</height>
        </rect>
       </property>
      </widget>
      <widget class="QLineEdit" name="pwdlineEdit">
       <property name="geometry">
        <rect>
         <x>170</x>
         <y>120</y>
         <width>113</width>
         <height>20</height>
        </rect>
       </property>
       <property name="echoMode">
        <enum>QLineEdit::Password</enum>
       </property>
      </widget>
      <widget class="QLabel" name="label">
       <property name="geometry">
        <rect>
         <x>90</x>
         <y>80</y>
         <width>54</width>
         <height>12</height>
        </rect>
       </property>
       <property name="text">
        <string>用户名：</string>
       </property>
      </widget>
      <widget class="QLabel" name="label_2">
       <property name="geometry">
        <rect>
         <x>90</x>
         <y>120</y>
         <width>54</width>
         <height>12</height>
        </rect>
       </property>
       <property name="text">
        <string>密码：</string>
       </property>
      </widget>
      <widget class="QPushButton" name="loginBtn">
       <property name="geometry">
        <rect>
         <x>80</x>
         <y>210</y>
         <width>75</width>
         <height>23</height>
        </rect>
       </property>
       <property name="text">
        <string>登录</string>
       </property>
      </widget>
      <widget class="QPushButton" name="exitBtn">
       <property name="geometry">
        <rect>
         <x>180</x>
         <y>210</y>
         <width>75</width>
         <height>23</height>
        </rect>
       </property>
       <property name="text">
        <string>退出</string>
       </property>
      </widget>
     </widget>
     <resources/>
     <connections>
      <connection>
       <sender>exitBtn</sender>
       <signal>clicked()</signal>
       <receiver>loginDlg</receiver>
       <slot>close()</slot>
       <hints>
        <hint type="sourcelabel">
         <x>217</x>
         <y>221</y>
        </hint>
        <hint type="destinationlabel">
         <x>199</x>
         <y>149</y>
        </hint>
       </hints>
      </connection>
     </connections>
    </ui>

widget.ui代码：

<?xml version="1.0" encoding="UTF-8"?>
    <ui version="4.0">
     <class>Widget</class>
     <widget class="QWidget" name="Widget">
      <property name="geometry">
       <rect>
        <x>0</x>
        <y>0</y>
        <width>400</width>
        <height>300</height>
       </rect>
      </property>
      <property name="windowTitle">
       <string>Widget</string>
      </property>
      <widget class="QLabel" name="label">
       <property name="geometry">
        <rect>
         <x>110</x>
         <y>100</y>
         <width>211</width>
         <height>81</height>
        </rect>
       </property>
       <property name="font">
        <font>
         <pointsize>36</pointsize>
        </font>
       </property>
       <property name="text">
        <string>登陆成功</string>
       </property>
      </widget>
     </widget>
     <layoutdefault spacing="6" margin="11"/>
     <resources/>
     <connections/>
    </ui>

源码下载：

[点击打开链接][Link 1]

[70]: /images/20220527/27fa64fc0fb645f2b46d6b84eb98a065.png
[70 1]: /images/20220527/87676aa33ba3426baf829609ffe71525.png
[70 2]: /images/20220527/b2c657a8077c44e68c5ddc897508c969.png
[Link 1]: https://download.csdn.net/download/kongshuai19900505/10360689