Qt / day02

1. 思维导图

2.使用手动连接，将登录框中的取消按钮使用qt4版本的连接到自定义的槽函数中，在自定义的槽函数中调用关闭函数; 将登录按钮使用qt5版本的连接到自定义的槽函数中，在槽函数中判断ui界面上输入的账号是否为"admin"，密码是否为"123456",如果账号密码匹配成功，则输出“登录成功”，并关闭该界面，如果匹配失败，则输出登录失败，并将密码框中的内容清空

project structure

代码

mywidget.h

#ifndef MYWIDGET_H
#define MYWIDGET_H

#include 
#include 
#include 
#include 
#include 
#include 

class MyWidget : public QWidget
{
    Q_OBJECT

public:
     QPushButton *pbtn_submit;
     QLineEdit *plnedt_usr;
     QLineEdit *plnedt_psw;

public:
    MyWidget(QWidget *parent = nullptr);
    ~MyWidget();

public slots:
    void on_btn_submit_clicked();

};
#endif // MYWIDGET_H

main.cpp

#include "mywidget.h"

#include 

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

mywidget.cpp

#include "mywidget.h"

MyWidget::MyWidget(QWidget *parent)
    : QWidget(parent),
      pbtn_submit(new QPushButton("login", this)),
      plnedt_usr(new QLineEdit(this)),
      plnedt_psw (new QLineEdit(this))
{
    //=== windows setup ===
    //setup windows size
    this->resize(600, 370);

    //set window fixed size
    this->setFixedSize(600, 370);

    //set window without frame
    this->setWindowFlag(Qt::FramelessWindowHint);

    //=== set label moive ===
    QLabel *plbl_screen = new QLabel(this);
    plbl_screen->resize(230,370);
    plbl_screen->move(0, 0);

    //setup label background color
    plbl_screen->setStyleSheet("background-color:#8EDE99  "); //#8EDDF9 , 142, 221, 249 rgb(147, 226, 254 )
    // create movie
    QMovie *pmv = new QMovie(":/pictrue/screen.gif");
     pmv->scaledSize();

    //set lable's movie
    plbl_screen->setMovie(pmv);
    //start moive
    pmv->start();
    //set to fit label
    plbl_screen->setScaledContents(true);

    //setup lable title
     QLabel *plbl_title = new QLabel("smart screen system",this);
     plbl_title->resize(150,20);
     plbl_title->move(460, 10);


    //setup LineEdit user name input
    //QLineEdit *plnedt_usr = new QLineEdit(this);
    plnedt_usr->setEchoMode(QLineEdit::Normal);
    plnedt_usr->setPlaceholderText("please input user name");
    plnedt_usr->resize(270, 30);
    plnedt_usr->move(290,180);

    //setup LineEdit password input
    //QLineEdit *plnedt_psw = new QLineEdit(this);
    plnedt_psw->setEchoMode(QLineEdit::Password);
    plnedt_psw->setPlaceholderText("please input password");
    plnedt_psw->resize(270, 30);
    plnedt_psw->move(290, 230);

    //setup pushbutton  
    pbtn_submit->resize(270, 30);
    pbtn_submit->move(290, 290);
    pbtn_submit->setStyleSheet("background-color: rgb(147, 226, 254 )");

    //setup cancel btn
    QPushButton *pbtn_canel = new QPushButton("cancel", this);
    pbtn_canel->resize(270, 30);
    pbtn_canel->move(290, 330);
    pbtn_canel->setStyleSheet("background-color: rgb(147, 226, 254 )");

    //btn_cancel connect based on qt4
    connect(pbtn_canel, SIGNAL(clicked()), this, SLOT(close()));

    //btn_login connect based on qt5
    connect(pbtn_submit, &QPushButton::clicked, this, &MyWidget::on_btn_submit_clicked);
}

MyWidget::~MyWidget()
{
}

void MyWidget::on_btn_submit_clicked()
{
    if(plnedt_usr->text() == "admin" && plnedt_psw->text()=="123456")
    {
        qDebug("success in login\n");
        this->close();
    }
    else
    {
        plnedt_psw->setText("");
    }
}

运行效果：

输入正确的用户名和密码，打印 登录成功

输入错误的用户名和密码，清除密码框内容