Question

Status:
I want to display 2 JPanels which contain images using a JSplitPane (one image at the top, one image at the bottom)

When I move the divider of the pane, I want both panels to resize accordingly. (that the images take up the maximum possible space)

The Problem:
I’m using a PropertyChangeListener to track the change of position of the divider, but the event seems to be fired before the actual “repaint?” of the window has taken place

What i’ve tried:
– repainting the component before reading the size

Minimum working example:

public class Main {
public static void main(String argv[]) {
    MyFrame f = new MyFrame();
}
}

class MyFrame extends JFrame {
/**
 * 
 */
private static final long serialVersionUID = 1L;
JPanel anyPanel, anyPanel2;
JSplitPane p;

public MyFrame() {
    PropertyChangeListener resizeHandler = new PropertyChangeListener() {
        @Override
        public void propertyChange(PropertyChangeEvent evt) {
            System.out.println(anyPanel.getHeight());
        }
    };

    anyPanel = new JPanel();
    anyPanel2 = new JPanel();
    p = new JSplitPane(JSplitPane.VERTICAL_SPLIT, anyPanel, anyPanel2);
    p.addPropertyChangeListener(JSplitPane.DIVIDER_LOCATION_PROPERTY, resizeHandler);
    getContentPane().add(p);
    this.add(p);
    this.pack();
    this.setVisible(true);
}
}

Answer 1

You need to add to the constructor

p.setContinuousLayout(true);