widget.h

#ifndef WIDGET_H
#define WIDGET_H

#include <QWidget>
#include <QIcon>    //图标类
#include <QPushButton>
#include <QLineEdit>    //行编辑
#include <QLabel>
#include <QTextEdit>
#include <QMovie>

class Widget : public QWidget
{
    Q_OBJECT

public:
    Widget(QWidget *parent = nullptr);
    ~Widget();
};
#endif // WIDGET_H

 widge.c

#include "widget.h"

Widget::Widget(QWidget *parent)
    : QWidget(parent)
{

    this -> setWindowTitle("CC");

    this -> setWindowIcon(QIcon("D:/图片/Camera Roll/QQ图片20211106093913.jpg"));

    this -> setStyleSheet("background-color : rgb(194,228,255)");

    this -> setWindowOpacity(0.9);

    this -> resize(540,410);

    this -> setFixedSize(540,410);

 // this -> setWindowFlag(Qt::FramelessWindowHint, 1);
 // this -> setWindowFlag(Qt::WindowFullscreenButtonHint , 0);



    //插入水印
    QLabel *lab1 = new QLabel(this);
    lab1-> resize(500, 300);
    lab1-> move(185, 120);
    lab1-> setPixmap(QPixmap("D:/图片/Camera Roll/风呤(1)(1).png"));
    lab1-> setScaledContents(true);

    //插图动图
    QLabel *gif = new QLabel(this);
    gif -> resize(540, 155);
    gif -> setStyleSheet("background-color:writh");
    QMovie *mv = new QMovie("D:/图片/hutao.webp");
    gif -> setMovie(mv);
    mv -> start();
    gif -> setScaledContents(true);

    //设置按钮
    QPushButton *btn1 = new QPushButton;
    btn1 -> setParent(this);
    btn1 -> setText("登录");
    btn1 -> setStyleSheet("background-color : rgb(80,2,250);color:white;border-radius:5px");
    btn1 -> resize(240,40);
    btn1 -> move(115, 300);

    QPushButton *btn2 = new QPushButton("注册", this);
//    btn2 -> setParent(this);
//    btn2 -> setText("注册");
    btn2 -> setStyleSheet("background-color : rgb(99,29,250)");
    btn2 -> resize(60,40);
    btn2 -> move(15, 360);

    QPushButton *btn3 = new QPushButton(QIcon("D:/图片/Camera Roll/QQ图片20211106093913.jpg"), "帮助", this);
    btn3 -> resize(60,40);
    btn3 -> move(460, 360);

    btn3 -> setEnabled(0);

    //行编辑器
    QLineEdit *edit = new QLineEdit;
    //行编辑器的占位
    edit -> setPlaceholderText("CC账号");
    edit -> setParent(this);
    edit -> move(155,196);
    edit -> resize(200,40);
    edit -> setEchoMode(QLineEdit::Normal);

    QLineEdit *edit2 = new QLineEdit;
    edit2 -> setPlaceholderText("CC密码");
    edit2-> setParent(this);
    edit2 -> move(155,250);
    edit2 -> resize(200,40);
    edit2 -> setEchoMode(QLineEdit::Password);

    //插入图片
    QLabel *lab = new QLabel(this);
    lab -> resize(40, 30);
    lab -> move(110, 200);
    lab -> setPixmap(QPixmap("D:/图片/卿本墨唧.png"));
    lab -> setScaledContents(true);

    QLabel *lock = new QLabel(this);
    lock -> resize(35, 35);
    lock -> move(115, 250);
    lock -> setPixmap(QPixmap("D:/图片/passwd.png"));
    lock -> setScaledContents(true);

}

Widget::~Widget()
{

}

main.c 

#include "widget.h"

#include <QApplication>

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