Qt---day2-信号与槽

1、思维导图

2、拖拽式

源文件

#include "mywidget.h"

#include "ui_mywidget.h"

MyWidget::MyWidget(QWidget *parent)

    : QWidget(parent)

    , ui(new Ui::MyWidget)

    ui->setupUi(this);

//按钮2

    this->btn2=new QPushButton("按钮2",this);

    btn2->resize(ui->pushButton->size());

    btn2->move(ui->pushButton->x(),ui->pushButton->y()+80);

    connect(this->btn2,&QPushButton::clicked,this,&MyWidget::bnt2_clicked);

//按钮3

    this->btn3 =new QPushButton("按钮3",this);

    btn3->resize(ui->pushButton->size());

    btn3->move(this->btn2->x(),this->btn2->y()+80);

    connect(this->btn3,&QPushButton::clicked,[&](){

        qDebug() << "lalalla";

});

MyWidget::~MyWidget()

    delete ui;

//通过槽创建的按钮生成的连接

void MyWidget::on_pushButton_clicked()

    qDebug() << "你点击了按钮1";

//按钮2的连接函数

void MyWidget::bnt2_clicked()

    static int num=0;

    if(num%3==0)

        this->setStyleSheet("background-color:red");

    }else if(num%3==1)

        this->btn2->setStyleSheet("background-color:green");

    else

        this->btn2->setStyleSheet("background-color:blue");

    num++;

头文件

#ifndef MYWIDGET_H

#define MYWIDGET_H

#include <QWidget>

#include <QDebug>

#include <QPushButton>

#include <QtTextToSpeech/QTextToSpeech>

QT_BEGIN_NAMESPACE

namespace Ui { class MyWidget; }

QT_END_NAMESPACE

class MyWidget : public QWidget

    Q_OBJECT

//signals:

//    void mySignal(void);

//public slots:

//    void mySlots(void);

    void bnt2_clicked();

public:

    MyWidget(QWidget *parent = nullptr);

    ~MyWidget();

private slots:

    void on_pushButton_clicked();

private:

    Ui::MyWidget *ui;

    QPushButton *btn2;

    QPushButton *btn3;

    QTextToSpeech *speecher;

};

#endif // MYWIDGET_H

3、代码式

头文件

#ifndef MYWIDGET_H

#define MYWIDGET_H

#include <QWidget>

#include<QIcon> //图标类

#include<QLabel> //标签类

#include<QMovie> //动图类

#include<QLineEdit> //行编辑器类

#include<QPushButton> //按钮类

#include <QDebug>

class MyWidget : public QWidget

    Q_OBJECT;

    QPushButton *btn;

     QLineEdit *edit1;

     QLineEdit *edit2;

public:

    MyWidget(QWidget *parent = nullptr);

    ~MyWidget();

    void  signal();

};

#endif // MYWIDGET_H

源文件

#include "mywidget.h"

MyWidget::MyWidget(QWidget *parent)

    : QWidget(parent)

    //==============窗口相关设置=======

    this->resize(540,415);

    this->setFixedSize(540,415);

    //窗口标题

    this->setWindowTitle("盗版QQ");

    //窗口图标

    this->setWindowIcon(QIcon(":/pictrue/qq.png"));

    //背景颜色

    this->setStyleSheet("background-color:white");

    //去掉头部

    this->setWindowFlag(Qt::FramelessWindowHint);

    //============标签相关设置=======

    QLabel *lab1 = new QLabel(this);

    //设置大小

    lab1->resize(540, 160);

    lab1->setStyleSheet("background-color:pink");

    //动图类 接收动图

    QMovie *mv = new QMovie(":/pictrue/zz.gif");

    //将动图放入标签中

    lab1->setMovie(mv);

    //让动图动起来

    mv->start();

    //自动适应

    lab1->setScaledContents(true);

    QLabel *lab2 = new QLabel(this);

    lab2->resize(30,30);

    lab2->move(120,210);

    lab2->setPixmap(QPixmap(":/pictrue/wodepeizhenshi.png"));

    lab2->setScaledContents(true);

    QLabel *lab3 = new QLabel(this);

    lab3->resize(30,30);

    lab3->move(120, 260);

    lab3->setPixmap(QPixmap(":/pictrue/passwd.jpg"));

    lab3->setScaledContents(true);

    //============行编辑器相关设置=======

    QLineEdit *edit1 = new QLineEdit(this);

    edit1->resize(275,30);

    edit1->move(155,210);

    edit1->setPlaceholderText("QQ号/手机号/邮箱");

    QLineEdit *edit2 = new QLineEdit(this);

    edit2->resize(275,30);

    edit2->move(155,260);

    edit2->setPlaceholderText("密码");

    edit2->setEchoMode(QLineEdit::Password);

    //============按钮相关设置=======

    QPushButton *btn = new QPushButton("登录",this);

    btn->resize(300,45);

    btn->move(120,345);

    //样式函数setStyleSheet()

    btn->setStyleSheet("background-color:rgb(8,189,253);border-radius:5px;color:white");

   // connect(btn,&QPushButton::clicked,edit1,&QLineEdit::textChanged);

  //  connect(btn,&QPushButton::clicked,edit2,&QLineEdit::textChanged);

    connect(edit1,&QLineEdit::textChanged,this,&MyWidget::signal);

     connect(edit2,&QLineEdit::textChanged,this,&MyWidget::signal);

MyWidget::~MyWidget()

void MyWidget::signal()

    if(edit1->text().size()>=5 && edit2->text().size()>=5){

              btn->setStyleSheet("background-color:green");

    if(edit1->text()=="paomao"&&edit2->text()=="555555")

        qDebug() << "登录成功";

        this->close();

    else

        qDebug() << "登录失败，密码账号有错误，请重新输入";

        edit1->clear();

        edit2->clear();