How to plot a graph with CAShapeLayer?

Question

Is it possible to draw just a curve with a given line width using CAShapeLayer? It seems it can only draw filled shapes. I want to draw an animated plot graph. Just a line, not a shape.

Answer 1

Well it seems you can in fact draw lines with CAShapeLayers. Try something like this:

UIBezierPath *graphPath = [UIBezierPath bezierPath];
[graphPath moveToPoint:CGPointMake(x, y)];
[graphPath addLineToPoint:CGPointMake(x, y + h)];
[graphPath closePath];

Then put it in a CAShapeLayer:

CAShapeLayer *shapeLayer = [[CAShapeLayer alloc] init];
[shapeLayer setFrame: aFrame];
[shapeLayer setPath: [graphPath CGPath]];
[shapeLayer setStrokeColor:[[UIColor blackColor] CGColor]];
[shapeLayer setMasksToBounds:YES];

You can change graphPath to plot any curve/line you want to graph.

Hope this helps!