ios 向 UICollectionViewCell 添加圆角和投影
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Adding rounded corner and drop shadow to UICollectionViewCell
提问by Vincent Yiu
So I already went through various posts on adding 2nd view for adding shadow, but I still cannot get it to work if I want to add it in UICollectionViewCell. I subclassed UICollectionViewCell, and here is my code where I add various UI elements to the cell's content view and adding shadow to the layer:
所以我已经阅读了关于添加第二个视图以添加阴影的各种帖子，但是如果我想将它添加到UICollectionViewCell. 我子类化了UICollectionViewCell，这里是我的代码，我将各种 UI 元素添加到单元格的内容视图，并向图层添加阴影：
[self.contentView setBackgroundColor:[UIColor whiteColor]];
self.layer.masksToBounds = NO;
self.layer.shadowOffset = CGSizeMake(0, 1);
self.layer.shadowRadius = 1.0;
self.layer.shadowColor = [UIColor blackColor].CGColor;
self.layer.shadowOpacity = 0.5;
[self.layer setShadowPath:[[UIBezierPath bezierPathWithRect:self.bounds] CGPath]];
I would like to know how to add rounded corner and shadow to UICollectionViewCell.
我想知道如何将圆角和阴影添加到UICollectionViewCell.
回答by Mike Sabatini
Neither of these solutions worked for me. If you place all your subviews into the UICollectionViewCell content view, which you probably are, you can set the shadow on the cell's layer and the border on the contentView's layer to achieve both results.
这些解决方案都不适合我。如果您将所有子视图放入 UICollectionViewCell 内容视图中，您可能就是这样，您可以在单元格图层上设置阴影和在 contentView 图层上设置边框以实现这两种结果。
cell.contentView.layer.cornerRadius = 2.0f;
cell.contentView.layer.borderWidth = 1.0f;
cell.contentView.layer.borderColor = [UIColor clearColor].CGColor;
cell.contentView.layer.masksToBounds = YES;
cell.layer.shadowColor = [UIColor blackColor].CGColor;
cell.layer.shadowOffset = CGSizeMake(0, 2.0f);
cell.layer.shadowRadius = 2.0f;
cell.layer.shadowOpacity = 0.5f;
cell.layer.masksToBounds = NO;
cell.layer.shadowPath = [UIBezierPath bezierPathWithRoundedRect:cell.bounds cornerRadius:cell.contentView.layer.cornerRadius].CGPath;
Swift 3.0
斯威夫特 3.0
self.contentView.layer.cornerRadius = 2.0
self.contentView.layer.borderWidth = 1.0
self.contentView.layer.borderColor = UIColor.clear.cgColor
self.contentView.layer.masksToBounds = true
self.layer.shadowColor = UIColor.black.cgColor
self.layer.shadowOffset = CGSize(width: 0, height: 2.0)
self.layer.shadowRadius = 2.0
self.layer.shadowOpacity = 0.5
self.layer.masksToBounds = false
self.layer.shadowPath = UIBezierPath(roundedRect: self.bounds, cornerRadius: self.contentView.layer.cornerRadius).cgPath
回答by Torre Lasley
Swift 3 version:
斯威夫特 3 版本：
cell.contentView.layer.cornerRadius = 10
cell.contentView.layer.borderWidth = 1.0
cell.contentView.layer.borderColor = UIColor.clear.cgColor
cell.contentView.layer.masksToBounds = true
cell.layer.shadowColor = UIColor.gray.cgColor
cell.layer.shadowOffset = CGSize(width: 0, height: 2.0)
cell.layer.shadowRadius = 2.0
cell.layer.shadowOpacity = 1.0
cell.layer.masksToBounds = false
cell.layer.shadowPath = UIBezierPath(roundedRect:cell.bounds, cornerRadius:cell.contentView.layer.cornerRadius).cgPath
回答by rocket101
In case it helps: Here is the swift for rounding the corners:
如果有帮助：这里是快速圆角：
cell.layer.cornerRadius = 10
cell.layer.masksToBounds = true
with cell being a variable controlling the cell: often, you will use this in override func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell
单元格是控制单元格的变量：通常，您将在 override func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell
Enjoy!
享受！
回答by Massimo Polimeni
Here the Swift 4solution, updated to round everycorners and not only the top corners:
这里是Swift 4解决方案，更新到每个角落，而不仅仅是顶角：
contentView.layer.cornerRadius = 6.0
contentView.layer.borderWidth = 1.0
contentView.layer.borderColor = UIColor.clear.cgColor
contentView.layer.masksToBounds = true
layer.shadowColor = UIColor.lightGray.cgColor
layer.shadowOffset = CGSize(width: 0, height: 2.0)
layer.shadowRadius = 6.0
layer.shadowOpacity = 1.0
layer.masksToBounds = false
layer.shadowPath = UIBezierPath(roundedRect: bounds, cornerRadius: contentView.layer.cornerRadius).cgPath
layer.backgroundColor = UIColor.clear.cgColor
回答by inzonemobileDev
Set the layerattributes for the cell, not contentView.
设置layer单元格的属性，而不是contentView.
CALayer * layer = [cell layer];
[layer setShadowOffset:CGSizeMake(0, 2)];
[layer setShadowRadius:1.0];
[layer setShadowColor:[UIColor redColor].CGColor] ;
[layer setShadowOpacity:0.5];
[layer setShadowPath:[[UIBezierPath bezierPathWithRect:cell.bounds] CGPath]];
回答by Alexander
SWIFT 4.2
斯威夫特 4.2
One should add this in your custom cell or cellForItemAt: If you are using the cellForItemAt: approach substitute self -> cell
应该在您的自定义单元格或 cellForItemAt 中添加它：如果您使用 cellForItemAt: 方法替代 self -> cell
self.layer.cornerRadius = 10
self.layer.borderWidth = 1.0
self.layer.borderColor = UIColor.lightGray.cgColor
self.layer.backgroundColor = UIColor.white.cgColor
self.layer.shadowColor = UIColor.gray.cgColor
self.layer.shadowOffset = CGSize(width: 2.0, height: 4.0)
self.layer.shadowRadius = 2.0
self.layer.shadowOpacity = 1.0
self.layer.masksToBounds = false
This will give you a cell with a rounded border and a drop shadow.
这将为您提供一个带有圆形边框和阴影的单元格。
回答by smileBot
Here's my answer, close to the others, but I add a corner radius to the layer otherwise the corners won't fill in correctly. Also, this makes a nice little extension on UICollectionViewCell.
这是我的答案，与其他答案接近，但我向图层添加了一个角半径，否则角将无法正确填充。此外，这对UICollectionViewCell.
extension UICollectionViewCell {
func shadowDecorate() {
let radius: CGFloat = 10
contentView.layer.cornerRadius = radius
contentView.layer.borderWidth = 1
contentView.layer.borderColor = UIColor.clear.cgColor
contentView.layer.masksToBounds = true
layer.shadowColor = UIColor.black.cgColor
layer.shadowOffset = CGSize(width: 0, height: 1.0)
layer.shadowRadius = 2.0
layer.shadowOpacity = 0.5
layer.masksToBounds = false
layer.shadowPath = UIBezierPath(roundedRect: bounds, cornerRadius: radius).cgPath
layer.cornerRadius = radius
}
}
}
You can call it in collectionView(_:cellForItemAt:)of the datasource once you dequeue your cell.
collectionView(_:cellForItemAt:)一旦您的单元出列，您就可以在数据源中调用它。
回答by Timothy Moose
You simply need to (a) set cornerRadiusand (b) set shadowPathto be a rounded rect with the same radius as cornerRadius:
您只需要 (a) 设置cornerRadius和 (b) 设置shadowPath为具有与以下相同半径的圆角矩形cornerRadius：
self.layer.cornerRadius = 10;
self.layer.shadowPath = [[UIBezierPath bezierPathWithRoundedRect:self.bounds cornerRadius:self.layer.cornerRadius] CGPath];
回答by Keith Holliday
I had to make some slight changes for Swift:
我不得不对Swift做一些小改动：
cell.contentView.layer.cornerRadius = 2.0;
cell.contentView.layer.borderWidth = 1.0;
cell.contentView.layer.borderColor = UIColor.clearColor().CGColor;
cell.contentView.layer.masksToBounds = true;
cell.layer.shadowColor = UIColor.grayColor().CGColor;
cell.layer.shadowOffset = CGSizeMake(0, 2.0);
cell.layer.shadowRadius = 2.0;
cell.layer.shadowOpacity = 1.0;
cell.layer.masksToBounds = false;
cell.layer.shadowPath = UIBezierPath(roundedRect:cell.bounds, cornerRadius:cell.contentView.layer.cornerRadius).CGPath;
回答by Tom Derry Marion Mantilla
This one worked for me
这个对我有用
cell.contentView.layer.cornerRadius = 5.0
cell.contentView.layer.borderColor = UIColor.gray.withAlphaComponent(0.5).cgColor
cell.contentView.layer.borderWidth = 0.5
let border = CALayer()
let width = CGFloat(2.0)
border.borderColor = UIColor.darkGray.cgColor
border.frame = CGRect(x: 0, y: cell.contentView.frame.size.height - width, width: cell.contentView.frame.size.width, height: cell.contentView.frame.size.height)
border.borderWidth = width
cell.contentView.layer.addSublayer(border)
cell.contentView.layer.masksToBounds = true
cell.contentView.clipsToBounds = true
