我有一个使用自定义JPanel绘制的Java绘画程序。当点击JPanel画一个小椭圆形(或者如果你愿意的话),每当你点击另一个地方时椭圆消失。坐标也得到更新,但椭圆形不留,它移动到任何地方的用户点击一个... ... 这里有一个自定义的JPanel代码:为什么这个Java绘画程序不能绘制多个椭圆形?
int xCord, yCord;
public class PaintPanel extends JPanel implements MouseListener {
// default serial whatever...
private static final long serialVersionUID = -6514297510194472060L;
// initial values
int xCord = -10;
int yCord = -10;
public PaintPanel() {
addMouseListener(this);
}
@Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(ProgramUI.currentColor);
g.fillOval(xCord, yCord, 8, 8);
repaint();
}
@Override
public void mouseClicked(MouseEvent m) {
}
@Override
public void mouseEntered(MouseEvent m) {
}
@Override
public void mouseExited(MouseEvent m) {
}
@Override
public void mousePressed(MouseEvent m) {
if (paintPanel.contains(m.getPoint())) {
xCord = m.getX();
yCord = m.getY();
System.out.println("x: " + xCord + " y: " + yCord);
}
}
@Override
public void mouseReleased(MouseEvent m) {
}
}
我需要鼠标的召开,不断作画一个椭圆直到放开鼠标按钮。这里唯一的问题是鼠标椭圆更新,但不保存它的原始位置。我该如何解决?