[英]Multiple Graphics2D Objects
我有一个JPanel的Graphics对象,并且工作正常:
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.geom.Rectangle2D;
import javax.swing.JPanel;
public class GraphicsTest extends JPanel
{
private Graphics2D g2d;
private String state;
private int x, y;
@Override
public void paintComponent(Graphics g)
{
super.paintComponent(g);
g2d = (Graphics2D) g;
g2d.setClip(0, 0, getWidth(), getHeight());
g2d.setColor(Color.BLACK);
g2d.drawString("STATE: " + state, 5, 15);
g2d.drawString("Mouse Position: " + x + ", " + y, 5, 30);
g2d.setColor(Color.red);
Rectangle2D r2d = new Rectangle2D.Double(x,y,10,10);
g2d.draw(r2d);
Test t = new Test();
super.add(t);
repaint();
}
public void setState(String state) { this.state = state; }
public String getState() { return state; }
public void setX(int x) { this.x = x; }
public void setY(int y) { this.y = y; }
}
我正在试验一个新的Graphics组件,当实例化一个新的Test并将其添加到GraphicsTest中时,什么也没发生。 我做错了什么?
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.geom.Rectangle2D;
import javax.swing.JComponent;
public class Test extends JComponent
{
private Graphics2D g2d;
private String state;
private int x, y;
@Override
public void paintComponent(Graphics g)
{
super.paintComponent(g);
g2d = (Graphics2D) g.create();
g2d.setColor(Color.GREEN);
g2d.fill(new Rectangle2D.Double(60, 60,
10, 10));
repaint();
}
public void setState(String state) { this.state = state; }
public String getState() { return state; }
public void setX(int x) { this.x = x; }
public void setY(int y) { this.y = y; }
}
谢谢!
您应该只添加一次Test组件并设置布局:
public GraphicTest()
{
super();
setLayout(new BorderLayout());
add(new Test(),BorderLayout.CENTER);
}
另外,不要保存Graphics2D
对象,因为一旦paintComponent
完成,它们将无效,并且不要在paintComponent
内部调用repaint
。 如果需要动画,请使用计时器,并在setXXX
方法中调用repaint
来更改组件的外观。
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.