我在故事板中的集合视图单元格中添加了一个图像。我想将图像设置为四舍五入。但是，它不起作用。
ViewController
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: indexPath) as! ContentCollectionViewCell
return cell
}
ContentCollectionViewCell
class ContentCollectionViewCell: UICollectionViewCell {
@IBOutlet weak var userProfileImageView: UIImageView!
required init?(coder aDecoder: NSCoder) {
// called
super.init(coder: aDecoder)
}
override init(frame: CGRect) {
// never called
super.init(frame: frame)
setRoundedImage()
}
func setRoundedImage() {
userProfileImageView.layer.cornerRadius = userProfileImageView.frame.width * 0.5
}
}
但它在 ViewController 中以这种方式工作。
为什么永远不会调用 ContentCollectionViewCell 中的init(frame: CGRect)？如果我想在UICollectionCell类中设置预定义的内容，最佳做法是什么？
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: indexPath) as! ContentCollectionViewCell
cell.userProfileImageView.layer.cornerRadius = cell.userProfileImageView.frame.width * 0.5
return cell
}
答案 0 :(得分：4)
尝试使用此代码我的帮助。
绕着牢房。 //舍入整个单元格
cell.contentView.layer.cornerRadius = 2.0;
cell.contentView.layer.borderWidth = 1.0;
cell.contentView.layer.borderColor = UIColor.clearColor().CGColor;
cell.contentView.layer.masksToBounds = true;
OR
在单元格类中添加以下内容//单元格的圆形图像视图
class ExploreCategoryCollectionViewCell: UICollectionViewCell
{
@IBOutlet var coverImage: UIImageView!
@IBOutlet var lblCoverName: UILabel!
@IBOutlet var lblArtistName: UILabel!
@IBOutlet var lblTags: UILabel!
@IBOutlet var lblE: UILabel!
override func awakeFromNib() {
super.awakeFromNib()
self.coverImage.layer.cornerRadius = 5.0
self.coverImage.layer.masksToBounds = true
}
答案 1 :(得分：2)
在单元格类中，您可以对单元格进行任何初始设置：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=Edge,chrome=1">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<link rel="shortcut icon" href="favicon.ico">
<title><%= @title %></title>
<%= csrf_meta_tags %>
<%= stylesheet_link_tag "application", :media => "all" %>
<!-- For third-generation iPad with high-resolution Retina display: -->
<!-- Size should be 144 x 144 pixels -->
<%= favicon_link_tag 'apple-touch-icon-144x144-precomposed.png', :rel => 'apple-touch-icon-precomposed', :type => 'image/png', :sizes => '144x144' %>
<!-- For iPhone with high-resolution Retina display: -->
<!-- Size should be 114 x 114 pixels -->
<%= favicon_link_tag 'apple-touch-icon-114x114-precomposed.png', :rel => 'apple-touch-icon-precomposed', :type => 'image/png', :sizes => '114x114' %>
<!-- For first- and second-generation iPad: -->
<!-- Size should be 72 x 72 pixels -->
<%= favicon_link_tag 'apple-touch-icon-72x72-precomposed.png', :rel => 'apple-touch-icon-precomposed', :type => 'image/png', :sizes => '72x72' %>
<!-- For non-Retina iPhone, iPod Touch, and Android 2.1+ devices: -->
<!-- Size should be 57 x 57 pixels -->
<%= favicon_link_tag 'apple-touch-icon-precomposed.png', :rel => 'apple-touch-icon-precomposed', :type => 'image/png' %>
<!-- For all other devices -->
<!-- Size should be 32 x 32 pixels -->
<%= favicon_link_tag 'favicon.ico', :rel => 'shortcut icon' %>
<%= javascript_include_tag "application" %>
<!-- Le HTML5 shim, for IE6-8 support of HTML elements -->
<!--[if lt IE 9]>
<script src="//cdnjs.cloudflare.com/ajax/libs/html5shiv/3.7.2/html5shiv.min.js" type="text/javascript"></script>
<![endif]-->
</head>
<body>
<div id="navbar" class="navbar navbar-default">
<div class="container-fluid">
<button type="button" class="navbar-toggle" data-toggle="collapse" data-target=".navbar-responsive-collapse">
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<div class="navbar-brand">
<%=link_to image_tag("knowuros-icon.gif", :alt=>"Brand", :class=>"Brand_Image visible-md visible-lg"), home_index_url %>
<span><%= link_to "Know Your Operating System", home_index_url, :id => "Brand_Text" %><small>One solution to all of your software problems</small></span>
</div>
<div class="navbar-collapse collapse navbar-responsive-collapse">
<ul class="nav navbar-nav">
<% Category.roots.each do |category| %>
<li class="<%= is_active?('')><%= link_to category.name, category, :class => "link_text" %></li>
<% end %>
<li class="<%= is_active?('contacts','new') %>"><%= link_to " ContactUs", new_contact_url, :class =>'glyphicon glyphicon-user' %></li>
</ul>
<ul class="nav navbar-nav navbar-right">
<% if auth_user_signed_in? %>
<li class="<%= is_active?('articles,'new') %>"><%= link_to " NewArticle", new_article_url, :class =>'glyphicon glyphicon-new-window' %></li>
<li><%= link_to " SignOut", destroy_auth_user_session_url, :method => 'delete', :class => "glyphicon glyphicon-log-out" %></li>
<% else %>
<li class="<%= is_active?('auth_users','sign_in') %>"><%= link_to " Login", new_auth_user_session_url, :class => "glyphicon glyphicon-log-in" %></li>
<li class="<%= is_active?('auth_users,'sign_up') %>"><%= link_to " Register", new_auth_user_registration_url, :class => "glyphicon glyphicon-registration-mark" %></li>
<% end %>
<form id= "search" class="navbar-form">
<div class="form-group">
<input type="text" class="form-control" placeholder="Search">
</div>
<button type="submit" class="btn btn-default glyphicon glyphicon-search">Search</button>
</form>
</ul>
</div>
</div>
</div>
<div class="container">
<div class="row">
<%= bootstrap_flash %>
<%= yield %>
</div><!--/row-->
<footer>
<p>© Company 2016</p>
</footer>
</div> <!-- /container -->
</body>
</html>答案 2 :(得分：0)
您必须为所有单元格设置它。将此代码写入cellForItemAt
cell.userProfileImageView.layer.cornerRadius = cell.userProfileImageView.frame.width * 0.5
cell.userProfileImageView!.clipsToBounds = true
希望它能起作用...... !!
答案 3 :(得分：0)
您应该在
中添加舍入代码行layoutSubviews()
不在init（）
中