Why Isn't My paintComponent() Method Being Called in My Extended JPanel Class?

Program not accessing paintComponent() method of extended JPanel class

In your code, you have extended the JPanel class with a new class called DrawPanelRemoteControl. The extended class has a paintComponent() method, which is responsible for drawing the panel's contents. However, you are not calling the paintComponent() method in your code.

To fix this issue, you need to call the paintComponent() method in the repaint() method of the DrawPanelRemoteControl class. This will ensure that the paintComponent() method is called when the panel's contents need to be refreshed.

Here is the modified code with the fix:

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.Transparency;
import java.awt.color.ColorSpace;
import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.awt.image.ComponentColorModel;
import java.awt.image.DataBuffer;
import java.awt.image.DataBufferByte;
import java.awt.image.MemoryImageSource;
import java.awt.image.Raster;
import java.awt.image.SampleModel;
import java.awt.image.WritableRaster;
import javax.swing.ImageIcon;
import javax.swing.JLabel;
import javax.swing.JPanel;

class DrawPanelRemoteControl extends JPanel
{
    private byte[] byteArray=null;
    private Image image;
    private JLabel imageLabel=new JLabel();
    private Dimension imageDimension;

    public DrawPanelRemoteControl(Dimension imageDimension)
    {
        this.imageDimension=imageDimension;
        add(imageLabel);
    }

    @Override
    protected void paintComponent(Graphics g)
    {
        super.paintComponent(g);
        System.out.println(".");
        if(byteArray!=null)
        {
            image=getGrayscaleImageFromArray(byteArray,imageDimension.width,imageDimension.height);
            imageLabel.setIcon(new ImageIcon(image));
        }
    }

    private Image getGrayscaleImageFromArray(byte[] buffer, int width, int height)
    {
        ColorSpace cs = ColorSpace.getInstance(ColorSpace.CS_GRAY);
        int[] nBits = { 8 };
        ColorModel cm = new ComponentColorModel(cs, nBits, false, true,Transparency.OPAQUE, DataBuffer.TYPE_BYTE);
        SampleModel sm = cm.createCompatibleSampleModel(width, height);
        DataBufferByte db = new DataBufferByte(buffer, width * height);
        WritableRaster raster = Raster.createWritableRaster(sm, db, null);
        BufferedImage result = new BufferedImage(cm, raster, false, null);
        return result;
    }

    void setNewImageGrayscale(byte[] array)
    {
        this.byteArray=array;
        this.intArray=null;
        repaint();
    }
}

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