JPanel background image
There is an error in your code here. You set your grafica
to null
the line before you dereference it. This will certainly throw a NullPointerException
. Instead of declaring your own Graphics object, you should use the one passed in to the method you will be using for painting. To do this in Swing, you should implement the paintComponent
method to paint your image, something like this:
public void paintComponent(Graphics grafica) {
grafica.drawImage(imgFondo, 0, 0, this);
}
Note that you don't want to be doing long running tasks like reading in Image files from disk in the painting thread. The above example assumes that you have already loaded the imgFondo
and have it stored such that it is accessible in the paintComponent
method.
lesolorzanov
Systems and computer engineer. MSc computer graphics. PhD and researcher. Working on biomedical imaging.
Updated on June 04, 2022Comments
-
lesolorzanov almost 2 years
This is my code, it indeed finds the image so that is not my concern, my concern is how to make that image be the background of the panel. I'm trying to work with Graphics but i doesnt work, any ideas?? please??
try { java.net.URL imgURL = MAINWINDOW.class.getResource(imagen); Image imgFondo = javax.imageio.ImageIO.read(imgURL); if (imgFondo != null) { Graphics grafica=null; grafica.drawImage(imgFondo, 0, 0, this); panel.paintComponents(grafica); } else { System.err.println("Couldn't find file: " + imagen); } } catch...