IOSButton自定义
+ (APCCustomBackButton *)customBackButtonWithTarget:(id)aTarget action:(SEL)anAction tintColor:(UIColor *)aTintColor
{
APCCustomBackButton *button = [APCCustomBackButton buttonWithType:UIButtonTypeCustom];
CGRect frame = CGRectMake(0.0, 0.0, kButtonWidth, kButtonHeight);
button.frame = frame;
[button addTarget:aTarget action:anAction forControlEvents:UIControlEventTouchUpInside];
CGMutablePathRef path = CGPathCreateMutable();
CGPoint p0 = CGPointMake(13.0, 12.0);
CGPathMoveToPoint(path, NULL, p0.x, p0.y);
CGPoint p1 = CGPointMake(2.0, 22.0);
CGPathAddLineToPoint(path, NULL, p1.x, p1.y);
CGPoint p2 = CGPointMake(13.0, 32.0);
CGPathAddLineToPoint(path, NULL, p2.x, p2.y);
CALayer *layer = button.layer;
CAShapeLayer *shaper = [[CAShapeLayer alloc] init];
shaper.frame = CGRectMake(0.0, 0.0, kLayerWidth, kLayerHeight);
shaper.bounds = CGRectMake(0.0, 0.0, kLayerWidth, kLayerHeight);
shaper.path = path;
shaper.lineWidth = kArrowLineWeight;
shaper.fillColor = [[UIColor clearColor] CGColor];
shaper.contentsScale = [[UIScreen mainScreen] scale];
shaper.strokeColor = aTintColor.CGColor;
[layer addSublayer:shaper];
CGPathRelease(path);
return button;
}