Assumption: this is pretty classic situation.
Assumption: this crash is due to threadA (triggered by jit.notify) and treadB (triggered by bang) attempting to access the same jit.render at the same time.

I spent all day toying around and trying things and researching threads (I’m a noob at that)

So I’m here to ask. Whats the best way to arrange things so this won’t crash. In real life, This a UI like a step sequencer. So the jitter notifiable is like me editing it with a mouse (quicker), and the bangs are like the clock causing a line to go across it(slower).

I was hoping to avoid repeatedly rendering al a qmetro because:
A, it would look choppy when using it as a UI object
B, it would be cpu intensive for times when I’m not using it.

Steps to crash,
instantiate mxj TestDrawCrash
hook a metro up to it,
drag around the jit.window

import com.cycling74.jitter.*;
import com.cycling74.max.*;
public class TestDrawCrash extends MaxObject  implements JitterNotifiable{

	JitterListener myListener;
	String name = "IwillCrash";
	CrashWindow cw; 

	public void notify (JitterEvent e){
		cw.draw();
	}

	public void bang(){
		cw.draw();
	}

	public TestDrawCrash(){
		myListener = new JitterListener(name,this);
		cw= new CrashWindow(name,300,300 );
	}

	class CrashWindow  {
		JitterObject myWindow;
		JitterObject myRender;
		String name;

		public CrashWindow(String name, int width, int height) {
			myRender = new JitterObject("jit.gl.render", name);
			myWindow = new JitterObject("jit.window", name);
			myWindow.setAttr("size", new Atom[] { Atom.newAtom(width),Atom.newAtom(height) });
			myWindow.setAttr("pos",new Atom[] { Atom.newAtom(0), Atom.newAtom(800) });
			myWindow.call("front");
			this.name = name; 

		}

		public void draw() {
				myRender.call("erase");
				myRender.call("drawclients");
				myRender.call("swap");
		}

	}
}