ios - 难以绘制阴影

Question

我正在尝试使用 UIBezierPath 为 UIView 创建自定义阴影。我希望它是一个倾斜的阴影，尽管我很难绘制自定义路径。

self.layer.shadowColor = [UIColor blackColor].CGColor;
self.layer.shadowOpacity = 0.7f;
self.layer.shadowOffset = CGSizeMake(-5.0f, 10.0f);
self.layer.shadowRadius = 5.0f;
self.layer.masksToBounds = NO;

CGFloat shadowDepth = 20.0;

UIBezierPath *path = [UIBezierPath bezierPath];
[path moveToPoint:CGPointMake(0.0, 0.0)];
[path addLineToPoint:CGPointMake(self.bounds.size.width, shadowDepth)];
[path stroke];

self.layer.shadowPath = path.CGPath;

影子没有出现。当我简单地将阴影的路径设置在视图的边界周围时，阴影会正确显示。因此，我一定是错误地绘制了贝塞尔路径。有任何想法吗？

这有效：

UIBezierPath *path = [UIBezierPath bezierPathWithRect:self.bounds];

Answer 1

您需要定义一个封闭的路径。你不需要抚摸它。

UIBezierPath *path = [UIBezierPath bezierPath];
CGRect bounds = self.bounds;
CGFloat xMax = CGRectGetMaxX(bounds);
CGFloat yMax = CGRectGetMaxY(bounds);
[path moveToPoint:CGPointMake(bounds.x + shadowDepth, bounds.y)];
[path addLineToPoint:CGPointMake(xMax + shadowDepth, bounds.y)];
[path addLineToPoint:CGPointMake(xMax, yMax)];
[path addLineToPoint:CGPointMake(bounds.x, yMax)];
[path closePath];
self.layer.shadowPath = path.CGPath;