我在一个应用程序上工作了几年,收到了一个简单的设计请求:在UIView上圆角并添加投影。做以下所给的事
我想要一个自定义的UIView…:我只是想要一个空白的白色视图与圆角和光滴阴影(没有照明效果)。我可以逐个执行这些操作,但通常会发生clipToBounds/maskToBounds冲突。
我在一个应用程序上工作了几年,收到了一个简单的设计请求:在UIView上圆角并添加投影。做以下所给的事
我想要一个自定义的UIView…:我只是想要一个空白的白色视图与圆角和光滴阴影(没有照明效果)。我可以逐个执行这些操作,但通常会发生clipToBounds/maskToBounds冲突。
当前回答
extension UIView {
func dropRoundedShadowForAllSides() {
let backgroundView = UIView(frame:self.frame)
let radius = frame.height/2
backgroundView.layer.masksToBounds = false
self.layer.masksToBounds = true
backgroundView.layer.shadowOffset = CGSize(width: 0.0, height: 0.0)
backgroundView.layer.shadowRadius = 4
backgroundView.layer.shadowOpacity = 0.4
let path = UIBezierPath()
// Start at the Top Left Corner + radius distance
path.move(to: CGPoint(x: 2*radius, y: 0.0))
// Move to the Top Right Corner - radius distance
path.addLine(to: CGPoint(x: backgroundView.frame.size.width - radius, y: 0.0))
// Move to top right corner + radius down as curve
let centerPoint1 = CGPoint(x:backgroundView.frame.size.width - radius,y:radius)
path.addArc(withCenter: centerPoint1, radius: radius, startAngle: 3*(.pi/2), endAngle: 0, clockwise: true)
// Move to the Bottom Right Corner - radius
path.addLine(to: CGPoint(x: backgroundView.frame.size.width, y: backgroundView.frame.size.height - radius))
// Move to top right corner + radius left as curve
let centerPoint2 = CGPoint(x:backgroundView.frame.size.width - radius,y:backgroundView.frame.size.height - radius)
path.addArc(withCenter: centerPoint2, radius: radius, startAngle: 0, endAngle: .pi/2, clockwise: true)
// Move to the Bottom Left Corner - radius
path.addLine(to: CGPoint(x: radius, y: backgroundView.frame.size.height))
// Move to left right corner - radius up as curve
let centerPoint3 = CGPoint(x:radius,y:backgroundView.frame.size.height - radius)
path.addArc(withCenter: centerPoint3, radius: radius, startAngle: .pi/2, endAngle: .pi, clockwise: true)
// Move to the top Left Corner - radius
path.addLine(to: CGPoint(x: 0, y: radius))
// Move to top right corner + radius down as curve
let centerPoint4 = CGPoint(x:radius,y:radius)
path.addArc(withCenter: centerPoint4, radius: radius, startAngle: .pi, endAngle: 3 * (.pi/2), clockwise: true)
path.close()
backgroundView.layer.shadowPath = path.cgPath
if let superView = self.superview {
superView.addSubview(backgroundView)
superView.sendSubview(toBack: backgroundView)
superView.bringSubview(toFront: self)
}
}
}
其他回答
我尝试了这篇文章中的很多解决方案,最终得到了下面的解决方案。这是完全证明解决方案,除非你需要在一个清晰的颜色视图下滴阴影。
- (void)addShadowWithRadius:(CGFloat)shadowRadius withOpacity:(CGFloat)shadowOpacity withOffset:(CGSize)shadowOffset withColor:(UIColor *)shadowColor withCornerradius:(CGFloat)cornerRadius
{
UIView *viewShadow = [[UIView alloc]initWithFrame:self.frame];
viewShadow.backgroundColor = [UIColor whiteColor];
viewShadow.layer.shadowColor = shadowColor.CGColor;
viewShadow.layer.shadowOffset = shadowOffset;
viewShadow.layer.shadowRadius = shadowRadius;
viewShadow.layer.shadowOpacity = shadowOpacity;
viewShadow.layer.cornerRadius = cornerRadius;
viewShadow.layer.masksToBounds = NO;
[self.superview insertSubview:viewShadow belowSubview:self];
[viewShadow setTranslatesAutoresizingMaskIntoConstraints:NO];
[self.superview addConstraint:[NSLayoutConstraint constraintWithItem:viewShadow attribute:NSLayoutAttributeWidth relatedBy:NSLayoutRelationEqual toItem:self attribute:NSLayoutAttributeWidth multiplier:1.0 constant:0]];
[self.superview addConstraint:[NSLayoutConstraint constraintWithItem:viewShadow attribute:NSLayoutAttributeHeight relatedBy:NSLayoutRelationEqual toItem:self attribute:NSLayoutAttributeHeight multiplier:1.0 constant:0]];
[self.superview addConstraint:[NSLayoutConstraint constraintWithItem:viewShadow attribute:NSLayoutAttributeCenterX relatedBy:NSLayoutRelationEqual toItem:viewShadow attribute:NSLayoutAttributeCenterX multiplier:1.0 constant:0]];
[self.superview addConstraint:[NSLayoutConstraint constraintWithItem:viewShadow attribute:NSLayoutAttributeCenterY relatedBy:NSLayoutRelationEqual toItem:viewShadow attribute:NSLayoutAttributeCenterY multiplier:1.0 constant:0]];
[self layoutIfNeeded];
self.layer.cornerRadius = cornerRadius;
self.layer.masksToBounds = YES;
}
一种方法是将带有圆角的视图放到带有投影的视图中。
UIView* roundedView = [[UIView alloc] initWithFrame: frame];
roundedView.layer.cornerRadius = 5.0;
roundedView.layer.masksToBounds = YES;
UIView* shadowView = [[UIView alloc] initWithFrame: frame];
shadowView.layer.shadowColor = [UIColor blackColor].CGColor;
shadowView.layer.shadowRadius = 5.0;
shadowView.layer.shadowOffset = CGSizeMake(3.0, 3.0);
shadowView.layer.shadowOpacity = 1.0;
[shadowView addSubview: roundedView];
然后你可以在任何你想要的地方添加shadowView。
如果你因为圆角、子视图和masksToBounds而挣扎,那么尝试使用我的函数:
- (UIView*)putView:(UIView*)view insideShadowWithColor:(UIColor*)color andRadius:(CGFloat)shadowRadius andOffset:(CGSize)shadowOffset andOpacity:(CGFloat)shadowOpacity
{
CGRect shadowFrame; // Modify this if needed
shadowFrame.size.width = 0.f;
shadowFrame.size.height = 0.f;
shadowFrame.origin.x = 0.f;
shadowFrame.origin.y = 0.f;
UIView * shadow = [[UIView alloc] initWithFrame:shadowFrame];
shadow.userInteractionEnabled = NO; // Modify this if needed
shadow.layer.shadowColor = color.CGColor;
shadow.layer.shadowOffset = shadowOffset;
shadow.layer.shadowRadius = shadowRadius;
shadow.layer.masksToBounds = NO;
shadow.clipsToBounds = NO;
shadow.layer.shadowOpacity = shadowOpacity;
[view.superview insertSubview:shadow belowSubview:view];
[shadow addSubview:view];
return shadow;
}
在你的视图中调用它。无论你的视图是否有圆角,无论它的大小,它的形状-一个漂亮的阴影将被绘制出来。
只要保留函数的返回值,这样当你想要删除表时就可以引用它(或者例如使用insertSubview:aboveView:)
下面的代码片段为UIView v添加了边框、边框半径和投影:
// border radius
[v.layer setCornerRadius:30.0f];
// border
[v.layer setBorderColor:[UIColor lightGrayColor].CGColor];
[v.layer setBorderWidth:1.5f];
// drop shadow
[v.layer setShadowColor:[UIColor blackColor].CGColor];
[v.layer setShadowOpacity:0.8];
[v.layer setShadowRadius:3.0];
[v.layer setShadowOffset:CGSizeMake(2.0, 2.0)];
Swift 5版本:
// border radius
v.layer.cornerRadius = 30.0
// border
v.layer.borderColor = UIColor.lightGray.cgColor
v.layer.borderWidth = 1.5
// drop shadow
v.layer.shadowColor = UIColor.black.cgColor
v.layer.shadowOpacity = 0.8
v.layer.shadowRadius = 3.0
v.layer.shadowOffset = CGSize(width: 2.0, height: 2.0)
您可以根据需要调整设置。
此外,将QuartzCore框架添加到您的项目中,并:
#import <QuartzCore/QuartzCore.h>
请看我关于masksToBounds的其他答案。
Note
这可能并不适用于所有情况。如果您发现此方法干扰您正在执行的其他绘图操作,请参阅此答案。
这里有一个肯定有效的解决方案!
我已经创建了UIView扩展所需的边应用阴影如下
enum AIEdge:Int {
case
Top,
Left,
Bottom,
Right,
Top_Left,
Top_Right,
Bottom_Left,
Bottom_Right,
All,
None
}
extension UIView {
func applyShadowWithCornerRadius(color:UIColor, opacity:Float, radius: CGFloat, edge:AIEdge, shadowSpace:CGFloat, cornerRadius: CGFloat) {
var sizeOffset:CGSize = CGSize.zero
switch edge {
case .Top:
sizeOffset = CGSize(width: 0, height: -shadowSpace)
case .Left:
sizeOffset = CGSize(width: -shadowSpace, height: 0)
case .Bottom:
sizeOffset = CGSize(width: 0, height: shadowSpace)
case .Right:
sizeOffset = CGSize(width: shadowSpace, height: 0)
case .Top_Left:
sizeOffset = CGSize(width: -shadowSpace, height: -shadowSpace)
case .Top_Right:
sizeOffset = CGSize(width: shadowSpace, height: -shadowSpace)
case .Bottom_Left:
sizeOffset = CGSize(width: -shadowSpace, height: shadowSpace)
case .Bottom_Right:
sizeOffset = CGSize(width: shadowSpace, height: shadowSpace)
case .All:
sizeOffset = CGSize(width: 0, height: 0)
case .None:
sizeOffset = CGSize.zero
}
self.layer.cornerRadius = cornerRadius
self.layer.masksToBounds = true
self.layer.shadowColor = color.cgColor
self.layer.shadowOpacity = opacity
self.layer.shadowOffset = sizeOffset
self.layer.shadowRadius = radius
self.layer.masksToBounds = false
self.layer.shadowPath = UIBezierPath(roundedRect:self.bounds, cornerRadius:self.layer.cornerRadius).cgPath
}
}
最后,你可以为你的UIView子类调用下面的阴影函数,你也可以指定边缘上应用阴影,尝试不同的变化根据你需要改变下面方法调用的参数。
viewRoundedToBeShadowedAsWell.applyShadowWithCornerRadius(color: .gray, opacity: 1, radius: 15, edge: AIEdge.All, shadowSpace: 15)
注意:如果仍然不工作,试着从主线程调用它
DispatchQueue.main.async {
viewRoundedToBeShadowedAsWell.applyShadowWithCornerRadius(color: .gray, opacity: 1, radius: 15, edge: AIEdge.All, shadowSpace: 15)
}
希望有人觉得这有用!
以下是结果图片: