The basic issue is that JTextArea
will paint it's background and it's text within the paintComponent
.
The simplest solution is to make the JTextArea
transparent and take over the control of painting the background.
This example basically fills the background with the background color, paints the image and then calls super.paintComponent
to allow the text to be rendered.
import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class TransparentTextArea {
public static void main(String[] args) {
new TransparentTextArea();
}
public TransparentTextArea() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new JScrollPane(new CustomTextArea()));
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class CustomTextArea extends JTextArea {
private BufferedImage image;
public CustomTextArea() {
super(20, 20);
try {
image = ImageIO.read(new File("/Users/swhitehead/Dropbox/MegaTokyo/Miho_Small_02.png"));
} catch (IOException ex) {
ex.printStackTrace();
}
}
@Override
public boolean isOpaque() {
return false;
}
@Override
protected void paintComponent(Graphics g) {
Graphics2D g2d = (Graphics2D) g.create();
g2d.setColor(getBackground());
g2d.fillRect(0, 0, getWidth(), getHeight());
if (image != null) {
int x = getWidth() - image.getWidth();
int y = getHeight() - image.getHeight();
g2d.drawImage(image, x, y, this);
}
super.paintComponent(g2d);
g2d.dispose();
}
}
}
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