JFrame 到图像而不显示 JFrame

2022-01-24 00:00:00 java swing jframe bufferedimage

我正在尝试将 JFrame 渲染到图像而不显示 JFrame 本身(类似于 this 问题正在询问).我试过使用这段代码:

I am trying to render a JFrame to an image without ever displaying the JFrame itself (similar to what this question is asking). I have tried using this piece of code:

private static BufferedImage getScreenShot(Component component)
{
    BufferedImage image = new BufferedImage(component.getWidth(), component.getHeight(), BufferedImage.TYPE_INT_RGB);
    // call the Component's paint method, using
    // the Graphics object of the image.
    component.paint(image.getGraphics());
    return image;
}

但是，这仅在 JFrame 的 setVisible(true) 设置时有效.这将导致图像显示在屏幕上，这不是我想要的.我也尝试过创建类似的东西:

However, this only works when the JFrame's setVisible(true) is set. This will cause the image to be displayed on the screen which is not something I want. I have also tried to create something like so:

public class MyFrame extends JFrame
{
    private BufferedImage bi;

    public MyFrame(String name, BufferedImage bi)
    { 
         this.bi = bi;
         super(name);
    }

    @Override
    public void paint(Graphics g)
    {
         g.drawImage(this.bufferedImage, 0, 0, null);
    }
}

然而，这会显示黑色图像(如上面的代码).我很确定我所追求的是可能的，问题是我真的找不到方法.我在自定义 Swing 组件方面的经验非常有限，因此我们将不胜感激.

This however displays black images (like the code above). I am pretty sure that what I am after is possible, the problem is that I can't really find how. My experience with custom Swing components is pretty limited, so any information will be appreciated.

谢谢.

推荐答案

这是一个可以解决问题的片段:

Here is a snippet that should do the trick:

Component c; // the component you would like to print to a BufferedImage
JFrame frame = new JFrame();
frame.setBackground(Color.WHITE);
frame.setUndecorated(true);
frame.getContentPane().add(c);
frame.pack();
BufferedImage bi = new BufferedImage(c.getWidth(), c.getHeight(), BufferedImage.TYPE_INT_ARGB);
Graphics2D graphics = bi.createGraphics();
c.print(graphics);
graphics.dispose();
frame.dispose();

相关文章