QT5 旋转图片Demo

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今天因为项目需要做了一个旋转的动画，下面是我的代码，有需要的可以参考：

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include "rotatewidget.h"
#include<QPropertyAnimation>
namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = nullptr);
    ~MainWindow();

private slots:
    void on_pushButton_clicked();

private:
    Ui::MainWindow *ui;
    RotateWidget* mRotateWidget;
    QPropertyAnimation* anim1;
    QPropertyAnimation* anim2;
};

#endif // MAINWINDOW_H

mainwindow.cpp的代码为：

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include "rotatewidget.h"
#include<QPropertyAnimation>
MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    mRotateWidget=new RotateWidget();
    mRotateWidget->setPixmap1(QPixmap(":/Resources/trash.png"));
//    mRotateWidget->setPixmap2(QPixmap(":/Resources/trash.png"));
    mRotateWidget->resize(300,300);
    anim1= new QPropertyAnimation (mRotateWidget, "rot1");
//     anim2=new QPropertyAnimation(mRotateWidget, "rot2");
     anim1->setStartValue(0);
//     anim2->setStartValue(0);
     anim1->setEndValue(359);
//     anim2->setEndValue(-359);
     anim1->setLoopCount(-1);
//     anim2->setLoopCount(-1);
     anim1->setDuration(5000);
//     anim2->setDuration(3000);
}

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

void MainWindow::on_pushButton_clicked()
{
    anim1->start();
//    anim2->start();
    mRotateWidget->show();
}

rotatewidget.h的文件代码为：

#ifndef ROTATEWIDGET_H
#define ROTATEWIDGET_H

#include <QWidget>

class RotateWidget : public QWidget
{
    Q_OBJECT
    Q_PROPERTY(int rot1 READ rot1 WRITE setRot1);
    Q_PROPERTY(int rot2 READ rot2 WRITE setRot2);
public:
    explicit RotateWidget(QWidget *parent = nullptr);
    void setPixmap1(QPixmap px);
    void setPixmap2(QPixmap px);
    int rot1();
    int rot2();

protected:
  void paintEvent(QPaintEvent *);

public slots:
  void setRot1(int r1);
  void setRot2(int r2);
private:
  int m_rot1;
  int m_rot2;
  QPixmap m_px1, m_px2;
};

#endif // ROTATEWIDGET_H

rotatewidget.cpp的代码为：

#include "rotatewidget.h"
#include<QPainter>
RotateWidget::RotateWidget(QWidget *parent) : QWidget(parent)
{
    m_rot1 = 0;
    m_rot2 = 0;

}

void RotateWidget::setPixmap1(QPixmap px) {
    m_px1 = px;
    update();
}

void RotateWidget::setPixmap2(QPixmap px)
 {
     m_px2 = px;
     update();
 }

int RotateWidget::rot1()
{

    return m_rot1;
}
int RotateWidget::rot2()
{
     return m_rot2;
}

void RotateWidget::setRot1(int r1)
{
    m_rot1 = r1;
    update();
}
void RotateWidget::setRot2(int r2)
{
    m_rot2 = r2;
    update();
}

void RotateWidget::paintEvent(QPaintEvent *) {
    QPainter p(this);
    p.setRenderHint(QPainter::Antialiasing);
    p.translate(width()/2, height()/2);
    if(!m_px1.isNull()) {
      p.save();
      p.rotate(m_rot1);
      QRect r = m_px1.rect();
      r.moveCenter(QPoint(0,0));
      p.drawPixmap(r, m_px1);
      p.restore();
    }
    if(!m_px2.isNull()) {
      p.save();
      p.rotate(m_rot2);
      QRect r = m_px2.rect();
      r.moveCenter(QPoint(0,0));
      p.drawPixmap(r, m_px2);
      p.restore();
    }
  }

下载链接：https://download.csdn.net/download/w5688414/11171223

参考文献

[1].rotate an image. https://www.qtcentre.org/threads/53765-rotate-an-image