QT控件的简单使用(持续更新)

忘是亡心i 2022-03-27 09:22 201阅读 0赞

记录一下学习QT中，用一些小例子来简单描述一下控件的使用方法：

## **1、QPixmap的使用** ##

MainWindow.h

#ifndef MAINWINDOW_H
    #define MAINWINDOW_H
    
    #include <QMainWindow>
    #include <QPixmap>
    #include <QLabel>
    
    namespace Ui {
    class MainWindow;
    }
    
    class MainWindow : public QMainWindow
    {
        Q_OBJECT
        
    public:
        explicit MainWindow(QWidget *parent = 0);
        ~MainWindow();
        
    private:
        Ui::MainWindow *ui;
        QPixmap *Picture ;
        QLabel  *lable ;
    };
    
    #endif // MAINWINDOW_H

MainWindow.cpp

运行结果:

![20190112232127193.png][]

## **2、QTimer的使用** ##

MainWindow.h

#ifndef MAINWINDOW_H
    #define MAINWINDOW_H
    
    #include <QMainWindow>
    #include <QTimer>
    #include <QLabel>
    #include <QPixmap>
    
    namespace Ui {
    class MainWindow;
    }
    
    class MainWindow : public QMainWindow
    {
        Q_OBJECT
        
    public:
        explicit MainWindow(QWidget *parent = 0);
        ~MainWindow();
        
    private:
        Ui::MainWindow *ui;
        QTimer *timer ;
        QLabel *lable ;
        QPixmap *Picture ;
    
    private slots:
        void Change_Picture();
    };
    
    #endif // MAINWINDOW_H

MainWindow.cpp

#include "mainwindow.h"
    #include "ui_mainwindow.h"
    
    MainWindow::MainWindow(QWidget *parent) :
        QMainWindow(parent),
        ui(new Ui::MainWindow)
    {
        ui->setupUi(this);
        lable  = new QLabel(this);
        this->setWindowFlags(Qt::FramelessWindowHint | Qt::WindowTitleHint | Qt::WindowSystemMenuHint);
        Picture = new QPixmap("C:/Users/Administrator/Desktop/QT_simple/QPixmap/QPixmap_Test/up.png");
        this->setFixedSize(Picture->height(),Picture->width());
        lable->setGeometry(Picture->height(),Picture->width(),Picture->height(),Picture->width());
        lable->move(0,0);
        lable->setPixmap(*Picture);
        lable->show();
        timer = new QTimer(this);
        connect(timer,SIGNAL(timeout()),this,SLOT(Change_Picture()));
        //开启一个定时器，用于图片的切换，每100ms切换一次
        timer->start(100);
    }
    //定时器槽函数，用于更换图片
    void MainWindow::Change_Picture()
    {
        static int status = 0 ;
        switch(status)
        {
            case 0:
                this->lable->setPixmap(QPixmap("C:/Users/Administrator/Desktop/QT_simple/QPixmap/QPixmap_Test/up.png"));
                status++ ;
                break ;
            case 1:
                this->lable->setPixmap(QPixmap("C:/Users/Administrator/Desktop/QT_simple/QPixmap/QPixmap_Test/down.png"));
                status++ ;
                break ;
            case 2:
                this->lable->setPixmap(QPixmap("C:/Users/Administrator/Desktop/QT_simple/QPixmap/QPixmap_Test/left.png"));
                status++ ;
                break ;
            case 3:
                this->lable->setPixmap(QPixmap("C:/Users/Administrator/Desktop/QT_simple/QPixmap/QPixmap_Test/right.png"));
                status = 0 ;
                break ;
        }
    
    }
    
    MainWindow::~MainWindow()
    {
        delete timer ;
        delete Picture ;
        delete lable ;
        delete ui;
    }

运行结果：

以下图片以up、dow、left、right的顺序，然后以100ms的执行速度切换。

![20190112233644385.png][]

## 3、QTime的使用 ##

mainwindow.h

#ifndef MAINWINDOW_H
    #define MAINWINDOW_H
    
    #include <QMainWindow>
    #include <QTimer>
    #include <QLabel>
    #include <QTime>
    #include <QString>
    
    namespace Ui {
    class MainWindow;
    }
    
    class MainWindow : public QMainWindow
    {
        Q_OBJECT
        
    public:
        explicit MainWindow(QWidget *parent = 0);
        ~MainWindow();
        
    private:
        Ui::MainWindow *ui;
        QTime  *time ;
        QTimer *timer ;
        QLabel *lable ;
        QString *time_Stirng ;
    
    private slots:
        void Change_Time();
    };
    
    #endif // MAINWINDOW_H

Mainwindow.cpp

#include "mainwindow.h"
    #include "ui_mainwindow.h"
    
    MainWindow::MainWindow(QWidget *parent) :
        QMainWindow(parent),
        ui(new Ui::MainWindow)
    {
        ui->setupUi(this);
        this->setWindowFlags(Qt::FramelessWindowHint | Qt::WindowTitleHint | Qt::WindowSystemMenuHint);
        time  = new QTime();
        timer = new QTimer(this);
        time_Stirng = new QString() ;
        lable  = new QLabel(this);
        time_Stirng->clear();
        lable->setGeometry(75,20,150,20);
        lable->move(0,0);
        connect(timer,SIGNAL(timeout()),this,SLOT(Change_Time()));
        lable->show();
        timer->start(1000);
    }
    
    void MainWindow::Change_Picture()
    {
        //获取当前的时间
        *time = time->currentTime();
        //将时间转换成字符串形式，并追加到QStirng上保存
        time_Stirng->append(time->toString("hh:mm:ss"));
        //将QStirng显示到QLabel上
        lable->setText(*time_Stirng);
        time_Stirng->clear();
    }
    
    MainWindow::~MainWindow()
    {
        delete time ;
        delete timer ;
        delete lable ;
        delete ui;
    }

运行结果：

![20190112235724417.png][]

[20190112232127193.png]: /images/20220327/6500e36f838f419dbf662d51c6f11171.png
[20190112233644385.png]: /images/20220327/42f64b6682f7467db89a2065e0bf9787.png
[20190112235724417.png]: /images/20220327/1ba4fa7f4a5143bd885cb177edf3f43e.png