how to get both selected and not selected look of the JCheckBox from LAF-CodePudding

I have a problem, because im trying to get both JCheckbox images selected and not selected so far ive been able to get Icon from the UIManager, but unfortunetly it doesnt have ticked version? Ive seen there are painters which paint those icons but if i run the following code it gives me NPE.

p = (Painter) UIManager.get("CheckBox[Enabled].iconPainter");
BufferedImage selected = new BufferedImage( 20, 20, BufferedImage.TYPE_INT_ARGB ) ;
p.paint((Graphics2D) selected.getGraphics(), null, 20, 20);

Anyone could help me with this one?

EDIT:

Basicly p is null after get method.

STACK:

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
    at addlayer.AddLayerUI.initOwn(AddLayerUI.java:47)
    at addlayer.AddLayerUI.<init>(AddLayerUI.java:28)
    at addlayer.AddLayerUI$1.run(AddLayerUI.java:136)
    at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:311)
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:758)
    at java.awt.EventQueue.access$500(EventQueue.java:97)
    at java.awt.EventQueue$3.run(EventQueue.java:709)
    at java.awt.EventQueue$3.run(EventQueue.java:703)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:728)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205)
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)

CODE:

package addlayer;

import java.awt.Graphics2D;
import java.awt.Toolkit;
import java.awt.image.BufferedImage;
import javax.swing.Icon;
import javax.swing.Painter;
import javax.swing.UIManager;

public class AddLayerUI extends javax.swing.JFrame {

    public AddLayerUI() {        
        initComponents();
        initOwn();
    }
    
    private void initOwn(){
        Icon icn ;
        icn = UIManager.getIcon("CheckBox.icon") ; //Works but gives only unchecked version of the check box, i need checked as well

        Painter p;

        p = (Painter) UIManager.get("CheckBox[Selected].iconPainter"); // returns null

        BufferedImage selected = new BufferedImage( 20, 20, BufferedImage.TYPE_INT_ARGB ) ;
        p.paint((Graphics2D) selected.getGraphics(), null, 20, 20);
    };
    
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        setTitle("AddLayer - TatukGIS DK11 sample");
        setIconImage(Toolkit.getDefaultToolkit().getImage(getClass().getResource("/resources/icon.png")));
        setSize(new java.awt.Dimension(800, 600));

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGap(0, 800, Short.MAX_VALUE)
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGap(0, 601, Short.MAX_VALUE)
        );

        pack();
    }// </editor-fold>                        

    public static void main(String args[]) {
        /* Set the Windows look and feel */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Windows".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(AddLayerUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(AddLayerUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(AddLayerUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(AddLayerUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>


        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new AddLayerUI().setVisible(true);
            }
        });
    }
    // Variables declaration - do not modify                     
    // End of variables declaration                   
}

CodePudding user response：

This example will use UI to draw the button in different states.

(There is an error in the image, the top left should be unchecked.)

import javax.swing.*;
import javax.swing.plaf.*;
import javax.swing.plaf.basic.*;
import java.awt.image.*;
import java.awt.*;
public class Icp{

    public static void main(String[] args){
        JCheckBox canon = new JCheckBox();
        Dimension d = canon.getPreferredSize();
        int w = (int)d.getWidth();
        int h = (int)d.getHeight();
        canon.setBounds(0, 0, w, h);
        BasicToggleButtonUI ui = (BasicToggleButtonUI)UIManager.getUI( canon );
        
        
        BufferedImage img = new BufferedImage(2*w, 2*h, BufferedImage.TYPE_INT_ARGB);
        
        Graphics g = img.getGraphics();
        ui.paint(g, canon);
        
        g.translate( w, 0);
        canon.setSelected(true);
        ui.paint(g, canon);
        
        g.translate(-w, h);
        canon.setEnabled(false);
        canon.setSelected(false);
        ui.paint(g, canon);
        
        g.translate(w, 0);
        canon.setSelected(true);
        ui.paint(g, canon);
        
        g.dispose();

        ImageIcon ico = new ImageIcon(img);
        
        JFrame frame = new JFrame();
        JLabel icn = new JLabel( ico );
        frame.add(icn);
        frame.pack();
        frame.setVisible(true);

        System.out.println( ui );
    }
}

I cast to a BasicToggleButtonUI because that had an icon method with it, but it is protected.