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
下面的方法最适合我 (这段代码位于UIView扩展中,因此self表示一些我们必须添加阴影和圆角的UIView)
- (void)addShadowViewWithCornerRadius:(CGFloat)radius {
UIView *container = self.superview;
if (!container) {
return;
}
UIView *shadowView = [[UIView alloc] init];
shadowView.translatesAutoresizingMaskIntoConstraints = NO;
shadowView.backgroundColor = [UIColor lightGrayColor];
shadowView.layer.cornerRadius = radius;
shadowView.layer.masksToBounds = YES;
[container addSubview:shadowView];
[container bringSubviewToFront:shadowView];
[container addConstraint:[NSLayoutConstraint constraintWithItem:shadowView
attribute:NSLayoutAttributeWidth
relatedBy:NSLayoutRelationEqual
toItem:self
attribute:NSLayoutAttributeWidth
multiplier:1.0
constant:0.0]];
[container addConstraint:[NSLayoutConstraint constraintWithItem:shadowView
attribute:NSLayoutAttributeLeading
relatedBy:NSLayoutRelationEqual
toItem:self
attribute:NSLayoutAttributeLeading
multiplier:1.0
constant:2.0]];
[container addConstraint:[NSLayoutConstraint constraintWithItem:shadowView
attribute:NSLayoutAttributeHeight
relatedBy:NSLayoutRelationEqual
toItem:self
attribute:NSLayoutAttributeHeight
multiplier:1.0
constant:0.0]];
[container addConstraint:[NSLayoutConstraint constraintWithItem:shadowView
attribute:NSLayoutAttributeTop
relatedBy:NSLayoutRelationEqual
toItem:self
attribute:NSLayoutAttributeTop
multiplier:1.0
constant:2.0]];
[container sendSubviewToBack:shadowView];
}
此代码与其他代码示例之间的主要区别在于,它将阴影视图添加为兄弟视图(而不是将当前视图添加为阴影视图的子视图),从而消除了以任何方式修改现有视图层次结构的需要。
其他回答
Swift 3 & IBInspectable解决方案: 灵感来自Ade的解决方案
首先,创建一个UIView扩展:
//
// UIView-Extension.swift
//
import Foundation
import UIKit
@IBDesignable
extension UIView {
// Shadow
@IBInspectable var shadow: Bool {
get {
return layer.shadowOpacity > 0.0
}
set {
if newValue == true {
self.addShadow()
}
}
}
fileprivate func addShadow(shadowColor: CGColor = UIColor.black.cgColor, shadowOffset: CGSize = CGSize(width: 3.0, height: 3.0), shadowOpacity: Float = 0.35, shadowRadius: CGFloat = 5.0) {
let layer = self.layer
layer.masksToBounds = false
layer.shadowColor = shadowColor
layer.shadowOffset = shadowOffset
layer.shadowRadius = shadowRadius
layer.shadowOpacity = shadowOpacity
layer.shadowPath = UIBezierPath(roundedRect: layer.bounds, cornerRadius: layer.cornerRadius).cgPath
let backgroundColor = self.backgroundColor?.cgColor
self.backgroundColor = nil
layer.backgroundColor = backgroundColor
}
// Corner radius
@IBInspectable var circle: Bool {
get {
return layer.cornerRadius == self.bounds.width*0.5
}
set {
if newValue == true {
self.cornerRadius = self.bounds.width*0.5
}
}
}
@IBInspectable var cornerRadius: CGFloat {
get {
return self.layer.cornerRadius
}
set {
self.layer.cornerRadius = newValue
}
}
// Borders
// Border width
@IBInspectable
public var borderWidth: CGFloat {
set {
layer.borderWidth = newValue
}
get {
return layer.borderWidth
}
}
// Border color
@IBInspectable
public var borderColor: UIColor? {
set {
layer.borderColor = newValue?.cgColor
}
get {
if let borderColor = layer.borderColor {
return UIColor(cgColor: borderColor)
}
return nil
}
}
}
然后,在界面构建器中选择你的UIView,设置阴影ON和角半径,如下所示:
结果!
旧线程仍然当前…
我编辑了Daniel Gindi的方法,使它可以用于按钮等。 如果有人需要圆角,或者想要将圆角和边框结合起来,它必须在视图层上设置,这个视图层被传递给这个方法。我还设置了栅格化来加快一点。
+ (UIView*)putView:(UIView*)view insideShadowWithColor:(CGColorRef)color
andRadius:(CGFloat)shadowRadius
andOffset:(CGSize)shadowOffset
andOpacity:(CGFloat)shadowOpacity
{
// Must have same position like "view"
UIView *shadow = [[UIView alloc] initWithFrame:view.frame];
shadow.layer.contentsScale = [UIScreen mainScreen].scale;
shadow.userInteractionEnabled = YES; // Modify this if needed
shadow.layer.shadowColor = color;
shadow.layer.shadowOffset = shadowOffset;
shadow.layer.shadowRadius = shadowRadius;
shadow.layer.masksToBounds = NO;
shadow.clipsToBounds = NO;
shadow.layer.shadowOpacity = shadowOpacity;
shadow.layer.rasterizationScale = [UIScreen mainScreen].scale;
shadow.layer.shouldRasterize = YES;
[view.superview insertSubview:shadow belowSubview:view];
[shadow addSubview:view];
// Move view to the top left corner inside the shadowview
// ---> Buttons etc are working again :)
view.frame = CGRectMake(0, 0, view.frame.size.width, view.frame.size.height);
return shadow;
}
丹尼尔。Gindi上面的回答对我很有用!然而,我不得不做一些小的调整-改变shadowFrame的大小与视图的帧大小相同,并启用用户交互。以下是更新后的代码:
+ (UIView*)putView:(UIView*)view insideShadowWithColor:(UIColor*)color andRadius:(CGFloat)shadowRadius andOffset:(CGSize)shadowOffset andOpacity:(CGFloat)shadowOpacity
{
CGRect shadowFrame; // Modify this if needed
// Modified this line
shadowFrame.size = CGSizeMake(view.frame.size.width, view.frame.size.height);
shadowFrame.origin.x = 0.f;
shadowFrame.origin.y = 0.f;
UIView * shadow = [[UIView alloc] initWithFrame:shadowFrame];
// Modified this line
shadow.userInteractionEnabled = YES;
shadow.layer.shadowColor = color.CGColor;
shadow.layer.shadowOffset = shadowOffset;
shadow.layer.shadowRadius = shadowRadius;
shadow.layer.masksToBounds = NO;
shadow.clipsToBounds = NO;
shadow.layer.shadowOpacity = shadowOpacity;
[shadow addSubview:view];
return shadow;
}
我想补充的是,在我的情况下,我试图将此添加到第三方视图控制器,即我没有对代码的直接控制。下面是我如何使用上面的函数:
UIView *shadow = [self putView:vc.view
insideShadowWithColor:[UIColor blackColor]
andRadius:5.0
andOffset:CGSizeMake(0.0, 0.0)
andOpacity:1.0];
vc.view = shadow;
vc.view.layer.cornerRadius = 5.0;
vc.view.layer.masksToBounds = YES;
你需要使用两个uiview来实现这一点。一个UIView会像阴影一样工作,另一个会为圆角边界工作。
下面是一个在协议帮助下的类方法的代码片段:
@implementation UIMethods
+ (UIView *)genComposeButton:(UIViewController <UIComposeButtonDelegate> *)observer;
{
UIView *shadow = [[UIView alloc]init];
shadow.layer.cornerRadius = 5.0;
shadow.layer.shadowColor = [[UIColor blackColor] CGColor];
shadow.layer.shadowOpacity = 1.0;
shadow.layer.shadowRadius = 10.0;
shadow.layer.shadowOffset = CGSizeMake(0.0f, -0.5f);
UIButton *btnCompose = [[UIButton alloc]initWithFrame:CGRectMake(0, 0,60, 60)];
[btnCompose setUserInteractionEnabled:YES];
btnCompose.layer.cornerRadius = 30;
btnCompose.layer.masksToBounds = YES;
[btnCompose setImage:[UIImage imageNamed:@"60x60"] forState:UIControlStateNormal];
[btnCompose addTarget:observer action:@selector(btnCompose_click:) forControlEvents:UIControlEventTouchUpInside];
[shadow addSubview:btnCompose];
return shadow;
}
在上面的代码中,btnCompose_click:将成为一个@required委托方法,该方法将在单击按钮时触发。
在这里我添加了一个按钮到我的UIViewController,像这样:
UIView *btnCompose = [UIMethods genComposeButton:self];
btnCompose.frame = CGRectMake(self.view.frame.size.width - 75,
self.view.frame.size.height - 75,
60, 60);
[self.view addSubview:btnCompose];
结果如下所示:
当为容器视图分配阴影路径时,我使用以下技巧解决了这个问题:
[UIBezierPath bezierPathWithRoundedRect:cell.bounds cornerRadius:12]
请注意,阴影的路径是一个圆角矩形,与单元格包含的背景具有相同的角半径:
//this is the border for the UIView that is added to a cell
cell.backgroundView.layer.cornerRadius = 12;
cell.backgroundView.layer.masksToBounds = YES;
cell.backgroundView.layer.borderColor = [UIColor darkGrayColor].CGColor;
cell.backgroundView.layer.borderWidth = 1;
//this is the shadow around the cell itself (cannot have round corners with borders and shadow, need to use two views
cell.layer.shadowRadius = 2;
cell.layer.cornerRadius = 12;
cell.layer.masksToBounds = NO;
[[cell layer] setShadowColor:[[UIColor darkGrayColor] CGColor]];
[[cell layer] setShadowOffset:CGSizeMake(0.0,0.0)];
[[cell layer] setShadowOpacity:1.0];
UIBezierPath *path = [UIBezierPath bezierPathWithRoundedRect:cell.bounds cornerRadius:12];
[[cell layer] setShadowPath:[path CGPath]];