Description Eyck Jentzsch 2015-10-27 16:45:43 EDT

Created attachment 257570 [details]
Stacktrace of the NPE

Hi,
I'm developing an E4 based application using TreeViewer with multiple columns. When PartRenderingEngine runs eventLoopIdle a NullPointerException is thrown. This happens frequently resulting in an nasty error message dialog.

Root cause is that Control.internal_new_GC() does not check if the graphicsContext is valid:

	NSGraphicsContext graphicsContext = NSGraphicsContext.currentContext();
	context = graphicsContext.id;

but NSGraphicsContext.currentContext() may return null:

	public static NSGraphicsContext currentContext() {
		long /*int*/ result = OS.objc_msgSend(OS.class_NSGraphicsContext, OS.sel_currentContext);
		return result != 0 ? new NSGraphicsContext(result) : null;
	}

Attached is a stacktrace, bundle is org.eclipse.swt.cocoa.macosx.x86_64_3.104.1.v20150825-0743.jar