Half circle slider.

Is it possible to draw only a half circle slider?

@fatuhoku
@hodgesmr
@eliotfowler
@kenthumphries
@ciotto

[douglasjunior]

I need too.

[eliotfowler]

@RokasAug Please refrain from auto-tagging everyone that has been marked as a contributer. If they are still interested in helping, they will be "watching" the project and will be notified automatically. If not, they all just got an unnecessary notification.

This is possible, but not without customization of the library code. You will basically need to do 2 things:

1. Restrict the slidable area to 0° to 180°
2. Modify -(void) drawLine:(CGContextRef)ctx to draw an unfilled arc instead of an unfilled circle as the background.