Qt 图片浏览器 实现图片的放大缩小翻转等功能

图片的功能

源码：

wiget.h

#ifndef WIDGET_H

#define WIDGET_H

#include <QPixmap>

#include <QImage>

#include <QPushButton>

#include <QHBoxLayout>

#include <QScrollArea>

#include <QLabel>

#include <QWidget>

#include <QPalette>

#include <QTimer>

#include <QString>

#include <QPainter>

#include <QPaintEvent>

#include <QDebug>

#include <QFileDialog>

#include <QStringList>

#include <QMessageBox>

#include <QDir>

#include <QFile>

namespace Ui {

class Widget;

}

class Widget : public QWidget

{

    Q_OBJECT  

public:

    explicit Widget(QWidget *parent = 0);

    ~Widget();

    QLabel *label;

    QTimer *timer;

    QPixmap pix;

private slots:

    void W_timergo();

    void W_go();

    void W_back();

    void W_close();

    void W_start();

    void W_stop();

    void W_max();

    void W_min();

    void W_flip();

    void W_delete();

    void W_open();

private:

    Ui::Widget *ui;

};

#endif // WIDGET_H

wiget.cpp

#include "widget.h"

#include "ui_widget.h"

static int num;

static int flag=1;

QString image[3] = {":/prefix1/1.jpg",":/prefix1/2.jpg",":/prefix1/3.jpg"};

Widget::Widget(QWidget *parent) :

    QWidget(parent),

    ui(new Ui::Widget)

{

    ui->setupUi(this);

    QPixmap pix;

    label = new QLabel;

    timer = new QTimer;

    QPalette palette;

    ui->scrollArea->setWidget(label);

    ui->scrollArea->setAlignment(Qt::AlignCenter);

    palette.setBrush(QPalette::Background,QBrush(QPixmap(":/prefix1/4.jpg")));

    this->setPalette(palette);

    connect(timer,SIGNAL(timeout()),this,SLOT(W_go()));

    connect(ui->pushButton,SIGNAL(clicked()),this,SLOT(W_go()));

    connect(ui->pushButton_3,SIGNAL(clicked()),this,SLOT(W_close()));

    connect(ui->pushButton_4,SIGNAL(clicked()),this,SLOT(W_start()));

    connect(ui->pushButton_5,SIGNAL(clicked()),this,SLOT(W_stop()));

    connect(ui->pushButton_2,SIGNAL(clicked()),this,SLOT(W_back()));

    connect(ui->pushButton_6,SIGNAL(clicked()),this,SLOT(W_max()));

    connect(ui->pushButton_7,SIGNAL(clicked()),this,SLOT(W_min()));

    connect(ui->pushButton_8,SIGNAL(clicked()),this,SLOT(W_flip()));

    connect(ui->pushButton_9,SIGNAL(clicked()),this,SLOT(W_delete()));

    connect(ui->pushButton_10,SIGNAL(clicked()),this,SLOT(W_open()));

}

void Widget::W_timergo()

{

   pix.load(image[num]);

   label->setPixmap(pix);

   if(num==2)

   {

        num = -1;

   }

   num++;

}

void Widget::W_go()

{

    timer->stop();

    pix.load(image[num]);

    label->setPixmap(pix);

    if(num==2)

    {

         num = -1;

    }

    num++;

}

void Widget::W_back()

{

    if(num < 0)

    {

        num = 2;

    }

    timer->stop();

    pix.load(image[num]);

    label->setPixmap(pix);

    num--;

}

void Widget::W_close()

{

    this->close();

}

void Widget::W_start()

{

     timer->start(2000);

}

void Widget::W_stop()

{

    timer->stop();

}

void Widget::W_max()

{

    timer->stop();

    float MaxX,MaxY;

    MaxX = pix.height();

    MaxY = pix.width();

    pix = pix.scaled(MaxX*2,MaxY*2,Qt::KeepAspectRatio);

    label->setPixmap(pix);

}

void Widget::W_min()

{

    timer->stop();

    float MaxX,MaxY;

    MaxX = pix.height();

    MaxY = pix.width();

    pix = pix.scaled(MaxX/2,MaxY/2,Qt::KeepAspectRatio);

    label->setPixmap(pix);

}

void Widget::W_flip()

{

    timer->stop();

    QMatrix leftmatrix;

    leftmatrix.rotate(90*flag);

    flag++;

    if(flag == 4)

    {

        flag = 0;

    }

    label->setPixmap(QPixmap(image[num]).transformed(leftmatrix,Qt::SmoothTransformation));

}

void Widget::W_delete()

{

    timer->stop();

    QStringList list;

    list=QFileDialog::getOpenFileNames(this,"open image","/","*.jpg");

    qDebug()<<list.at(0);

    pix.load(list.at(0));

    label->setPixmap(pix);

    QMessageBox::StandardButton rb = QMessageBox::question(NULL,"Warning",

                    "Do you want to delete the picture?

",QMessageBox::Yes | QMessageBox::No, QMessageBox::Yes);

       if(rb == QMessageBox::Yes)

       {

           QFile::remove(list.at(0));//刪除文件

       }

}

void Widget::W_open()

{

    timer->stop();

    QStringList list;

    list=QFileDialog::getOpenFileNames(this,"open image","/","*.jpg");

     qDebug()<<list.at(0);

    pix.load(list.at(0));

    label->setPixmap(pix);

}

Widget::~Widget()

{

    delete ui;

}

main.cpp

#include "widget.h"

#include <QApplication>

int main(int argc, char *argv[])

{

    QApplication a(argc, argv);

    Widget w;

    w.show();

    return a.exec();

}