java GUI 动态改变Jpanel背景

Question

我要做个面板,上面有个时钟,然后还有个按钮可以动态改变面板的背景图片,同时不影响时钟的显示,请问怎样做?谢谢.

Answer 1

如果是在同一个面板上，重写paintConponent方法，把时钟和背景都画上

Answer 2

class Clock extends JPanel{
    private BufferedImage backgroundImage = null;
    
    ... // 其他方法    public void setBackgroundImage(BufferedImage image){
this.backgroundImage = image;
repaint();
    }    public void paintComponent(Graphics g){
super.paintComponent(g);
Graphics2D g2d = (Graphics2D)g; if(backgroundImage != null){
    g2d.drawImage(backgroundImage,0,0);
}

... // 其他绘制
    }
}