iphone - UIView with a Dashed line

Question

What I have:

To create this line, I basically have an UIView and I do the following:

void setLayerToLineFromAToB(CALayer *layer, CGPoint a, CGPoint b, CGFloat lineWidth)
{
    CGPoint center = { 0.5 * (a.x + b.x), 0.5 * (a.y + b.y) };
    CGFloat length = sqrt((a.x - b.x) * (a.x - b.x) + (a.y - b.y) * (a.y - b.y));
    CGFloat angle = atan2(a.y - b.y, a.x - b.x);

    layer.position = center;
    layer.bounds = (CGRect) { {0, 0}, { length + lineWidth, lineWidth } };
    layer.transform = CATransform3DMakeRotation(angle, 0, 0, 1);
}

Note: This code was found here on stackoverflow, so if someone can give me the reference to it I would appreciate.

What I want:

Ok so the "only" thing I need is to create this pattern on the UIView. I know I am able to do this using Quartz2D (a simple way to do it can be found here). But I want to do it by manipulating the CALayer and not going to to the draw method. Why? Because of the transformation I am making on my UIView, I am not able to draw correctly using the draw method.

Edit 1:

Just to illustrate my problem:

Normally what you have is UIView and then you basically just draw something in it (in this case a simple line). The solution I found to get rid of the "gray" area, was to instead of drawing something, just transform the UIView itself. It work well, if you want a fully filled line, the problem comes when you want a dashed one.

Answer 1

Check UIBezierPath setLineDash:count:phase: method:

- (void)setLineDash:(const CGFloat *)pattern count:(NSInteger)count phase:(CGFloat)phase` method. 

This allows you to draw dashed lines.

1. First add a CAShapeLayer. Add it as sublayer to your UIView. It has a path property.
2. Now make an object of UIBezierPath. Draw the line using setLineDash.

For example:

 UIBezierPath *path = [UIBezierPath bezierPath];
 //draw a line
 [path moveToPoint:yourStartPoint]; //add yourStartPoint here
 [path addLineToPoint:yourEndPoint];// add yourEndPoint here
 [path stroke];

 CGFloat dashPattern[] = {2.0f,6.0f,4.0f,2.0f}; //make your pattern here
 [path setLineDash:dashPattern count:4 phase:3];

 UIColor *fill = [UIColor blueColor];
 shapelayer.strokeStart = 0.0;
 shapelayer.strokeColor = fill.CGColor;
 shapelayer.lineWidth = 5.0;
 shapelayer.lineJoin = kCALineJoinMiter;
 shapelayer.lineDashPattern = [NSArray arrayWithObjects:[NSNumber numberWithInt:10],[NSNumber numberWithInt:7], nil];
 shapelayer.lineDashPhase = 3.0f;
 shapelayer.path = path.CGPath;

Note: This answer provides a hint so you can improvise accordingly to your requirement(s).