Using a Custom JList CellRenderer that extends JPanel

[Diargg]

I'm trying to create a scrollable list that supports Drag n Drop from a list of graphics (the JList) to the main area (another JPanel). I'd like to use JList because it has the slection/DnD things baked in. If it's untenable, I can live with trying something else.

Anyway, the issue I'm running into is inside the CellRenderer I'm trying to write. Inside getListCellComponent I would like to put together a graphic based on the data received from the list. However, I seem to be unable to access any graphics from within this class (getGraphics() returns null). Am I overlooking something obvious here? Should I write something that the renderer can call that will put together the component and pass it up through? Should I be looking into designing a list from scratch using JPanels, layout managers, and a JScrollPane?

Guess it's more of a design question than a code question, but I'd like to get more experienced opinions before I go any further.

Thanks

[Fubarable]

You should almost never be calling getGraphics any way. Consider creating and posting a small compilable program that runs, that uses internet-available resources (such as for images) and that demonstrates you problem -- an SSCCE, and I'll bet we'll be better able to help you.

[DarrylBurke]

Moved from New to Java

db

[Diargg]

I ended up going with a method that passes another component to the renderer. Hopefully this makes sense.

public class listbar extends JPanel{
public listbar{
         DefaultListModel<int> set = new DefaultListModel<int>();
		for(int i=0;i<10;i++){
			set.addElement(i);
		}
                JList<int> Jset = new JList<File>(set);
		Jset.setCellRenderer(new CustomCellRenderer());
                add(Jset);
                setVisible(true);
         }
}
//List construction

class CustomCellRenderer extends JPanel implements ListCellRenderer<File>{
//In the same file...
	private HashMap<int, JPanel> map = new HashMap<int,JPanel>();
	
	public CustomCellRenderer(){
		setOpaque(true);
	}
	
	@Override
	public Component getListCellRendererComponent(JList<? extends int> list,
			int f, int index, boolean isSelected, boolean hasFocus) {
		
		if(!map.containsKey(f)){  //Memoized
			JPanel panel = new JPanel();
			box temp = new box(f); 
			panel.add(temp);
			map.put(f, panel);
		}
		JPanel temp = map.get(f);
		
		if (isSelected)temp.setBackground(Color.LIGHT_GRAY);
		else temp.setBackground(Color.WHITE);
		if(hasFocus)temp.setBorder(BorderFactory.createDashedBorder(Color.BLACK,1,2));
		else temp.setBorder(BorderFactory.createLineBorder(Color.BLACK));
		
		add(temp);  //Not sure about this add()
		setVisible(true);
		return temp;
	}
	
}

class box extends JPanel{
	private int i=0;//A bit more than just this of course
	
	public box(int i){
		this.i=i;
		setSize(90, 10*i);
		setPreferredSize(getSize());
		setBorder(BorderFactory.createLineBorder(Color.BLACK));
			
	}
	
	protected void paintComponent(Graphics g){
		g.drawString(""+i,2,12);
	}
}

Any suggestions as to a better implementation than this? I didn't include the scrolling, and I still have to implement the DnD that would essentially transfer the int represented by the image to somewhere else to be converted into another image.