使用透明度在彼此之上添加多个图像

Question

是否可以将多个图像添加到单个JPanel并使用顶部Image的透明通道查看底层Image ？

Answer 1

You can, but is easier if you create your own version of JPanel extending the JPanel class. Create a subclass of JPanel and override the paint method. In the paint method, just paint one image over another image.

public class MiPanel extends JPanel {
  List<Image> images;

  ...

  void addIMage( Image im) {
    images.add( im)
  }

  @Override
  public void paint( Graphics g) {
    Graphics2D g2d = (Graphics2D)g;

    ...
    for ( Image im :images) {
      g2d.drawImage( im, 0,0, null);
    }
    ...
  }

Create a List to store the images and a method to add images to the list. Then, in the paint method, paint all the images. Of course, if the images have transparency, you will be able to see the "under" images. If you create the images on the fly, remember to use Color with alpha channel. If you load images from files, I recomend you to use PNGs.