登录框：

#include "mainwindow.h"

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
{
    //窗口设置
    this->setFixedSize(600,600);   //大小
    this->setWindowTitle("MUMU");  //文本内容
    this->setWindowOpacity(0.8);  //透明度
    this->setWindowIcon(QIcon("C:\\Users\\12199\\Desktop\\交友.png"));  //图标

    //QLabel
    QLabel *lab1 = new QLabel(this);
    lab1->resize(600,230);
    lab1->setPixmap(QPixmap("C:\\Users\\12199\\Desktop\\%BFE6[VFX23LJ_$$CFVHGAL.png"));
    lab1->setScaledContents(true); //设置文本自适应

    QLabel *lab2 = new QLabel("账号",this);
    lab2->resize(60,40);
    lab2->move(70,280);
    lab2->setAlignment(Qt::AlignCenter);
    lab2->setPixmap(QPixmap("C:\\Users\\12199\\Desktop\\icon_交友.png"));
    lab2->setScaledContents(true); //设置文本自适应

    QLabel *lab3 = new QLabel("密码",this);
    lab3->resize(60,40);
    lab3->move(70,340);
    lab3->setAlignment(Qt::AlignCenter);
    lab3->setPixmap(QPixmap("C:\\Users\\12199\\Desktop\\密码.png"));
    lab3->setScaledContents(true); //设置文本自适应

    //QLineEdit
    QLineEdit *edit1 = new QLineEdit("账户",this);
    edit1->resize(230,40);
    edit1->move(150,280);

    QLineEdit *edit2 = new QLineEdit("密码",this);
    edit2->resize(230,40);
    edit2->move(150,340);
    edit2->setEchoMode(QLineEdit::Password);

    //QPushbutton
    QPushButton *btn1 = new QPushButton("登录", this);
    btn1->resize(80,30);
    btn1->move(350,450);
    btn1->setIcon(QIcon("C:\\Users\\12199\\Desktop\\征婚交友.png"));

    QPushButton *btn2 = new QPushButton("取消", this);
    btn2->resize(80,30);
    btn2->move(480,450);
    btn2->setIcon(QIcon("C:\\Users\\12199\\Desktop\\已取消.png"));


}

MainWindow::~MainWindow()
{
}

思维导图：