登陆界面

#include "mainwindow.h"
#include "ui_mainwindow.h"MainWindow::MainWindow(QWidget *parent): QMainWindow(parent), ui(new Ui::MainWindow)
{ui->setupUi(this);//设置固定大小this->setFixedSize(400,300);//设置窗口标题this->setWindowTitle("HUAQI");//设置窗口图标this->setWindowIcon(QIcon("D:\\Qt\\icon\\icon\\wodepeizhenshi.png"));//构建两个按钮QPushButton *btn1=new QPushButton(QIcon("D:\\Qt\\icon\\icon\\login.png"),"登录",this);btn1->resize(100,40);btn1->move(100,250);QPushButton *btn2=new QPushButton(QIcon("D:\\Qt\\icon\\icon\\cancel.png"),"取消",this);btn2->resize(btn1->size());btn2->move(btn1->x()+150,btn1->y());//构建两个行编辑器QLineEdit *edit1=new QLineEdit(this);edit1->resize(200,30);edit1->setEchoMode(QLineEdit::Password);edit1->setText("123456");edit1->move(125,btn1->y()-50);QLineEdit *edit2=new QLineEdit(this);edit2->resize(200,30);edit2->setText("admin");edit2->move(125,edit1->y()-50);//构建三个标签QLabel *lab1=new QLabel(this);lab1->resize(30,30);lab1->setPixmap(QPixmap("D:\\Qt\\icon\\icon\\passwd.jpg"));lab1->setScaledContents(true);lab1->move(edit1->x()-40,edit1->y());QLabel *lab2=new QLabel(this);lab2->resize(lab1->size());lab2->setPixmap(QPixmap("D:\\Qt\\icon\\icon\\userName.jpg"));lab2->setScaledContents(true);lab2->move(edit2->x()-40,edit2->y());QLabel *lab3=new QLabel(this);lab3->resize(400,120);lab3->setPixmap(QPixmap("D:\\Qt\\icon\\icon\\logo.png"));lab3->setScaledContents(true);
}MainWindow::~MainWindow()
{delete ui;
}

将工程文件进行注释

1.工程管理文件

QT       += core gui
#引入QT所需要的库，core是核心库，gui是图形开发相关类的库
greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
#超过4。0版本的，加上widgets库
CONFIG += c++11
#支持C++11版本的
# The following define makes your compiler emit warnings if you use
# any Qt feature that has been marked 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 it uses 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
#对源文件进行管理
SOURCES += \main.cpp \mywnd.cpp
#对头文件进行管理
HEADERS += \mywnd.h
#对UI文件进行管理
FORMS += \mywnd.ui# Default rules for deployment.
qnx: target.path = /tmp/$${TARGET}/bin
else: unix:!android: target.path = /opt/$${TARGET}/bin
!isEmpty(target.path): INSTALLS += target

2.头文件

#ifndef MYWND_H
#define MYWND_H
//防止头文件重复包含//父类的头文件
#include <QWidget>QT_BEGIN_NAMESPACE
//声明UI文件对应的命名空间
namespace Ui { class MyWnd; }
QT_END_NAMESPACE
//公共继承QWidget
class MyWnd : public QWidget
{//信号和槽的元对象，没有元对象，信号和槽就不能使用Q_OBJECTpublic://构造函数，带有一个默认变量MyWnd(QWidget *parent = nullptr);~MyWnd();private://可以使用UI指针调用Ui界面中的组件Ui::MyWnd *ui;
};
#endif // MYWND_H

3.源文件

#include "mywnd.h"
#include "ui_mywnd.h"MyWnd::MyWnd(QWidget *parent)//先行调用父类有参构造函数: QWidget(parent)//给自己类中的Ui指针舒适化空间, ui(new Ui::MyWnd)
{//调用Uiui->setupUi(this);
}MyWnd::~MyWnd()
{//释放指针空间delete ui;
}

4.主程序文件

#include "mywnd.h"
//引入应用程序的头文件
#include <QApplication>int main(int argc, char *argv[])
{//实例化一个应用程序对象QApplication a(argc, argv);//实例化自定义的图形化界面的类MyWnd w;//展示界面w.show();//阻塞等待应用程序，等待用户操作return a.exec();
}