我的java应用程序中有一个函数可以将图像旋转x度。现在我弹出一个简单的JOptionPane,它将旋转角度收集为用户的双倍。
是否有一个java小部件可以让用户点击/拖动到圆上的某个点来直观地设置旋转角度?
已经签出: AWT, SWT, 摆动
答案 0 :(得分:2)
为什么不自己创建一个?这应该很简单。这是我在几分钟内制作的快速草稿......您可以根据自己的喜好进行更改:
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionAdapter;
import java.awt.event.MouseMotionListener;
import java.awt.geom.AffineTransform;
import javax.swing.JFrame;
import javax.swing.JPanel;
/**
* @author Savvas Dalkitsis
*/
public class Test {
public static void main(String[] args) {
JFrame f = new JFrame("Test");
final JRotation rot = new JRotation();
f.getContentPane().add(rot);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.pack();
f.setVisible(true);
rot.addMouseMotionListener(new MouseMotionAdapter() {
@Override
public void mouseDragged(MouseEvent e) {
System.out.println(rot.getRotation());
}
});
}
}
@SuppressWarnings("serial")
class JRotation extends JPanel implements MouseMotionListener {
private double rotation = 1;
public double getRotation() {
return rotation;
}
public JRotation() {
setPreferredSize(new Dimension(100, 100));
addMouseMotionListener(this);
}
@Override
protected void paintComponent(Graphics g) {
Graphics2D g2 = (Graphics2D)g.create();
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2.setPaint(Color.white);
g2.fillRect(0, 0, getWidth(), getHeight());
g2.setPaint(Color.black);
AffineTransform t = g2.getTransform();
g2.translate(getWidth()/2, getHeight()/2);
g2.rotate(-rotation);
g2.drawLine(0, 0, Math.max(getWidth(),getHeight()), 0);
g2.setTransform(t);
}
@Override
public void mouseDragged(MouseEvent e) {
int x = e.getX();
int y = e.getY();
int midX = getWidth() / 2;
int midY = getHeight() / 2;
if (x>midX) {
if (y>midY) { // fourth quadrant
rotation = 2*Math.PI - Math.atan((y-midY)/(double)(x-midX));
} else { // first quadrant
rotation = Math.atan((midY-y)/(double)(x-midX));
}
} else {
if (y>midY) { // third quarter
rotation = Math.PI + Math.atan((y-midY)/(double)(midX-x));
} else { // second quarter
rotation = Math.PI - Math.atan((midY-y)/(double)(midX-x));
}
}
repaint();
}
public void mouseMoved(MouseEvent e) {}
}