How do I draw a proper parallelogram that can be animated on iPhone?

Question

I'm trying to do something very simple: I need some parallelograms in my program. These are attached to other objects, all of which are UIView s. It's important that I be able to animate these, since the objects they are attached to can also be animated.

I've figured out how to use the transform in UIView / CALayer to do this, but the problem is that these sheared UIView s don't look very nice: there is no anti-aliasing of the edges.

Is there some other way to do this? I would like to use UIView s, since I also use them for user interaction and animation is so much easier than drawing by hand. I don't want to use OpenGL for this.

Answer 1

You can enable edge antialiasing by modifying your app's Info.plist .

You need to add the UIViewEdgeAntialiasing key, with Boolean YES as the value. The human-friendly name in Xcode's Info editor is “Renders with edge antialiasing”.

Answer 2

用UIBezierPath绘制它们。