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PORedrawing a path using CGContextStrokePath after initial load
 

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    <p>I have a basic map view in my app which contains a set of user definable way points. When the view is loaded I draw a path connecting the way points. This works well.</p> <p>However, when the user drags a way point around the view, I would like it to re-draw the paths and that is my problem. I dont know how to hacant get it to draw anything after the first time. Here's my code:</p> <pre><code>- (void)drawRect:(CGRect)rect { ////// works perfectly context = UIGraphicsGetCurrentContext(); CGContextSetRGBStrokeColor(context, 1, 0, 1, .7); CGContextSetLineWidth(context, 20.0); WaypointViewController *w = [arrayOfWaypoints objectAtIndex:0]; CGPoint startPoint = w.view.center; CGContextMoveToPoint(context, startPoint.x, startPoint.y); for (int i = 1; i&lt;[arrayOfWaypoints count]; i++) { WaypointViewController *w2 = [arrayOfWaypoints objectAtIndex:i]; CGPoint nextPoint = w2.view.center; CGContextAddLineToPoint(context,nextPoint.x, nextPoint.y); } CGContextStrokePath(context); } - (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event { if (moving) { UITouch *touch = [touches anyObject]; currentWaypoint.view.center = [touch locationInView:self]; [delegate setUserInteraction:NO]; [self drawInContext:context]; [NSThread detachNewThreadSelector:@selector(drawInContext:) toTarget:self withObject:nil]; } } - (void)drawInContext:(CGContextRef)context { ///gets called, but does nothing CGContextSetRGBStrokeColor(context, 1, 0, 1, .7); CGContextSetLineWidth(context, 20.0); WaypointViewController *w = [arrayOfWaypoints objectAtIndex:0]; CGPoint startPoint = w.view.center; CGContextMoveToPoint(context, startPoint.x, startPoint.y); for (int i = 1; i&lt;[arrayOfWaypoints count]; i++) { WaypointViewController *w2 = [arrayOfWaypoints objectAtIndex:i]; CGPoint nextPoint = w2.view.center; CGContextAddLineToPoint(context,nextPoint.x, nextPoint.y); } CGContextStrokePath(context); } </code></pre>
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