記錄一下學習QT中，用一些小例子來簡單描述一下控制元件的使用方法：

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

#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);
    //設定圖片資源到QPixmap上
    Picture = new QPixmap("C:/Users/Administrator/Desktop/QT_simple/QPixmap/QPixmap_Test/linux_logo.png");
    this->setFixedSize(Picture->height(),Picture->width());
    lable->setGeometry(Picture->height(),Picture->width(),Picture->height(),Picture->width());
    lable->move(0,0);
    //將圖片設定到QLabel控制元件上
    lable->setPixmap(*Picture);
    lable->show();
}

MainWindow::~MainWindow()
{
    delete Picture ;
    delete lable ;
    delete ui;
}
 

執行結果:

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()));
    //開啟一個定時器，用於圖片的切換，每100ms切換一次
    timer->start(100);
}
//定時器槽函式，用於更換圖片
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;
}

執行結果：

以下圖片以up、dow、left、right的順序，然後以100ms的執行速度切換。

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()
{
    //獲取當前的時間
    *time = time->currentTime();
    //將時間轉換成字串形式，並追加到QStirng上儲存
    time_Stirng->append(time->toString("hh:mm:ss"));
    //將QStirng顯示到QLabel上
    lable->setText(*time_Stirng);
    time_Stirng->clear();
}

MainWindow::~MainWindow()
{
    delete time ;
    delete timer ;
    delete lable ;
    delete ui;
}

執行結果：