如何在Swing中逐渐旋转图像？

当用户点击一个button时，我有一个旋转的图像。 但它不工作。

我希望看到图像逐渐旋转到90度，直到停止，但没有。 单击button时图像必须逐渐旋转90度。

我已经创build了一个SSCCE来展示问题。 请将CrossingPanelSSCE类中的图像replace为您select的任何图像。 只需将图像放在images文件夹中，并将其命名为images/railCrossing.JPG 。

RotateButtonSSCE

 import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.Action; import javax.swing.BorderFactory; import javax.swing.JButton; import javax.swing.JPanel; public class RotateButtonSSCE extends JPanel implements ActionListener{ private JButton rotate = new JButton("Rotate"); private VisualizationPanelSSCE vis = new VisualizationPanelSSCE(); public RotateButtonSSCE() { this.setBorder(BorderFactory.createTitledBorder("Rotate Button ")); this.rotate.addActionListener(this); this.add(rotate); } public void actionPerformed(ActionEvent ev) { vis.rotatetheCrossing(); } } 

CrossingPanelSSCE

 import java.awt.Color; import java.awt.Dimension; import java.awt.FlowLayout; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.Image; import java.awt.Rectangle; import java.awt.Toolkit; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.geom.AffineTransform; import javax.swing.BorderFactory; import javax.swing.JPanel; import javax.swing.border.TitledBorder; public class CrossingPanelSSCE extends JPanel{ private static final long serialVersionUID = 1L; // private data members private Image crossingImage; private int currentRotationAngle; private int imageWidth; private int imageHeight; private AffineTransform affineTransform; private boolean clockwise; private static int ROTATE_ANGLE_OFFSET = 2; private int xCoordinate; private int yCoordinate; private static javax.swing.Timer timer; private void initialize(){ this.crossingImage = Toolkit.getDefaultToolkit().getImage("images/railCrossing.JPG"); this.imageWidth = this.getCrossingImage().getWidth(this); this.imageHeight = this.getCrossingImage().getHeight(this); this.affineTransform = new AffineTransform(); currentRotationAngle = 90; timer = new javax.swing.Timer(20, new MoveListener()); } public CrossingPanelSSCE(int x, int y) { this.setxCoordinate(x); this.setyCoordinate(y); this.setPreferredSize(new Dimension(50, 50)); this.setBackground(Color.red); TitledBorder border = BorderFactory.createTitledBorder("image"); this.setLayout(new FlowLayout()); this.initialize(); } public void paintComponent(Graphics grp){ Rectangle rect = this.getBounds(); Graphics2D g2d = (Graphics2D)grp; g2d.setColor(Color.BLACK); this.getAffineTransform().setToTranslation(this.getxCoordinate(), this.getyCoordinate()); //rotate with the rotation point as the mid of the image this.getAffineTransform().rotate(Math.toRadians(this.getCurrentRotationAngle()), this.getCrossingImage().getWidth(this) /2, this.getCrossingImage().getHeight(this)/2); //draw the image using the AffineTransform g2d.drawImage(this.getCrossingImage(), this.getAffineTransform(), this); } public void rotateCrossing(){ System.out.println("CurrentRotationAngle: " + currentRotationAngle); this.currentRotationAngle += ROTATE_ANGLE_OFFSET; //int test = currentRotationAngle % 90; if(currentRotationAngle % 90 == 0){ setCurrentRotationAngle(currentRotationAngle); timer.stop(); } //repaint the image panel repaint(); } void start() { if (timer != null) { timer.start(); } } private class MoveListener implements ActionListener { public void actionPerformed(ActionEvent e) { rotateCrossing(); } } public Image getCrossingImage() { return crossingImage; } public void setCrossingImage(Image crossingImage) { this.crossingImage = crossingImage; } public int getCurrentRotationAngle() { return currentRotationAngle; } public void setCurrentRotationAngle(int currentRotationAngle) { this.currentRotationAngle = currentRotationAngle; } public int getImageWidth() { return imageWidth; } public void setImageWidth(int imageWidth) { this.imageWidth = imageWidth; } public int getImageHeight() { return imageHeight; } public void setImageHeight(int imageHeight) { this.imageHeight = imageHeight; } public AffineTransform getAffineTransform() { return affineTransform; } public void setAffineTransform(AffineTransform affineTransform) { this.affineTransform = affineTransform; } public boolean isClockwise() { return clockwise; } public void setClockwise(boolean clockwise) { this.clockwise = clockwise; } public int getxCoordinate() { return xCoordinate; } public void setxCoordinate(int xCoordinate) { this.xCoordinate = xCoordinate; } public int getyCoordinate() { return yCoordinate; } public void setyCoordinate(int yCoordinate) { this.yCoordinate = yCoordinate; } public javax.swing.Timer getTimer() { return timer; } public void setTimer(javax.swing.Timer timer) { this.timer = timer; } } 

VisualizationPanelSSCE

 import gui.CrossingPanel; import java.awt.BasicStroke; import java.awt.Color; import java.awt.Dimension; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.RenderingHints; import java.awt.Shape; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.geom.GeneralPath; import javax.swing.BorderFactory; import javax.swing.JPanel; import javax.swing.SwingUtilities; import javax.swing.border.TitledBorder; import application.Robot2; public class VisualizationPanelSSCE extends JPanel{ //private data members private GeneralPath path; private Shape horizontalRail; private Shape verticalRail; private static int LENGTH = 350; private CrossingPanelSSCE crossingP; private void initializeComponents(){ this.path = new GeneralPath(); this.horizontalRail = this.createHorizontalRail(); this.verticalRail = this.createVerticalRail(); this.crossingP = new CrossingPanelSSCE(328,334); } public VisualizationPanelSSCE(){ this.initializeComponents(); this.setPreferredSize(new Dimension(400,400)); TitledBorder border = BorderFactory.createTitledBorder("Rotation"); this.setBorder(border); } public GeneralPath getPath() { return path; } public void setPath(GeneralPath path) { this.path = path; } private Shape createHorizontalRail(){ this.getPath().moveTo(5, LENGTH); this.getPath().lineTo(330, 350); this.getPath().closePath(); return this.getPath(); } private Shape createVerticalRail(){ this.getPath().moveTo(350, 330); this.getPath().lineTo(350,10); this.getPath().closePath(); return this.getPath(); } public void paintComponent(Graphics comp){ super.paintComponent(comp); Graphics2D comp2D = (Graphics2D)comp; BasicStroke pen = new BasicStroke(15.0F, BasicStroke.CAP_BUTT,BasicStroke.JOIN_ROUND); comp2D.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); comp2D.setPaint(Color.black); comp2D.setBackground(Color.WHITE); comp2D.draw(this.horizontalRail); this.crossingP.paintComponent(comp2D); } public CrossingPanelSSCE getCrossingP() { return crossingP; } public void setCrossingP(CrossingPanelSSCE crossingP) { this.crossingP = crossingP; } public void rotatetheCrossing(){ Runnable rotateCrossing1 = new Runnable(){ public void run() { crossingP.start(); } }; SwingUtilities.invokeLater(rotateCrossing1); } } 

TestGUISSCE包含了主要的方法。

 import java.awt.Dimension; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.MouseAdapter; import java.awt.event.MouseEvent; import java.util.Random; import javax.swing.*; public class TestGUISSCE{ private RotateButtonSSCE rotate = new RotateButtonSSCE(); private VisualizationPanelSSCE vision = new VisualizationPanelSSCE(); public void createGui(){ JFrame frame = new JFrame("Example"); frame.setSize(new Dimension(500, 500)); JPanel pane = new JPanel(); pane.add(this.vision); pane.add(rotate); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.add(pane); frame.setVisible(true); } public static void main(String[] args) { new TestGUISSCE().createGui(); } } 

Answer 1

除了@ tulskiy的有用的观察，我会补充两点：

1. 总是在事件派发线程上构buildGUI，如下所示。

2. 一个sscce应该是一个简短的，自包含的，正确的（可编译的）例子 。 为了方便，不要求其他人重新创build多个公共类; 使用顶级（包私有）或嵌套类。 由于这是graphics问题，请使用反映问题的公共或合成图像。

在下面的例子中， paintComponent()改变graphics上下文的变换来实现旋转。 请注意，这些操作是以声明顺序的（明显）相反的方式执行的：首先，图像的中心被翻译为原点; 第二，图像旋转; 第三，图像的中心被翻译成面板的中心。 您可以通过调整面板大小来查看效果。

附录：另请参阅使用AffineTransform替代方法 。

 package overflow; import java.awt.*; import java.awt.event.*; import java.awt.image.BufferedImage; import java.util.Random; import javax.swing.*; /** * @see https://stackoverflow.com/questions/3371227 * @see https://stackoverflow.com/questions/3405799 */ public class RotateApp { private static final int N = 3; public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { @Override public void run() { JFrame frame = new JFrame(); frame.setLayout(new GridLayout(N, N, N, N)); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); for (int i = 0; i < N * N; i++) { frame.add(new RotatePanel()); } frame.pack(); frame.setVisible(true); } }); } } class RotatePanel extends JPanel implements ActionListener { private static final int SIZE = 256; private static double DELTA_THETA = Math.PI / 90; private final Timer timer = new Timer(25, this); private Image image = RotatableImage.getImage(SIZE); private double dt = DELTA_THETA; private double theta; public RotatePanel() { this.setBackground(Color.lightGray); this.setPreferredSize(new Dimension( image.getWidth(null), image.getHeight(null))); this.addMouseListener(new MouseAdapter() { @Override public void mousePressed(MouseEvent e) { image = RotatableImage.getImage(SIZE); dt = -dt; } }); timer.start(); } @Override public void paintComponent(Graphics g) { super.paintComponent(g); Graphics2D g2d = (Graphics2D) g; g2d.translate(this.getWidth() / 2, this.getHeight() / 2); g2d.rotate(theta); g2d.translate(-image.getWidth(this) / 2, -image.getHeight(this) / 2); g2d.drawImage(image, 0, 0, null); } @Override public void actionPerformed(ActionEvent e) { theta += dt; repaint(); } @Override public Dimension getPreferredSize() { return new Dimension(SIZE, SIZE); } } class RotatableImage { private static final Random r = new Random(); static public Image getImage(int size) { BufferedImage bi = new BufferedImage( size, size, BufferedImage.TYPE_INT_ARGB); Graphics2D g2d = bi.createGraphics(); g2d.setRenderingHint( RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); g2d.setPaint(Color.getHSBColor(r.nextFloat(), 1, 1)); g2d.setStroke(new BasicStroke(size / 8)); g2d.drawLine(0, size / 2, size, size / 2); g2d.drawLine(size / 2, 0, size / 2, size); g2d.dispose(); return bi; } } 

Answer 2

旋转图标代码使用AffineTransform围绕其中心旋转。

Answer 3

 this.crossingP.paintComponent(comp2D); 

永远不要这样做！ 您的CrossingPane不会添加到任何组件，因此repaint（）不起任何作用。 您可以通过在paintComponent（）方法中添加打印件来检查它。 所以你需要将CrossingPane添加到VisualizationPane中：

 setLayout(new BorderLayout()); add(crossingP, BorderLayout.CENTER); 

图像居中有一些问题，但这不应该很难解决。

PS。 再次阅读有关布局和绘画。