ios 如何在 UITableView 的顶部添加额外的分隔符？
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How do I add an extra separator to the top of a UITableView?
提问by richt
I have a view for the iPhone that is basically split in two, with an informational display in the top half, and a UITableView for selecting actions in the bottom half. The problem is that there is no border or separator above the first cell in the UITableView, so the first item in the list looks funny. How can I add an extra separator at the top of the table, to separate it from the display area above it?
我有一个 iPhone 视图，它基本上分为两部分，上半部分是信息显示，下半部分是用于选择操作的 UITableView。问题是 UITableView 中第一个单元格上方没有边框或分隔符，因此列表中的第一项看起来很有趣。如何在表格顶部添加额外的分隔符，将其与其上方的显示区域分开？
Here's the code to build the cells - it's pretty straightforward. The overall layout is handled in a xib.
这是构建单元格的代码 - 非常简单。整体布局在 xib 中处理。
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = @"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
}
switch(indexPath.row) {
case 0: {
cell.textLabel.text = @"Action 1";
break;
}
case 1: {
cell.textLabel.text = @"Action 2";
break;
}
// etc.......
}
return cell;
}
回答by Ortwin Gentz
To replicate the standard iOS separator lines, I use a 1 px (not 1 pt) hair line tableHeaderViewwith the table view's separatorColor:
为了复制标准的 iOS 分隔线，我使用 1 px（不是 1 pt）的头发线tableHeaderView和表格视图的separatorColor：
// in -viewDidLoad
self.tableView.tableHeaderView = ({
UIView *line = [[UIView alloc]
initWithFrame:CGRectMake(0, 0,
self.tableView.frame.size.width, 1 / UIScreen.mainScreen.scale)];
line.backgroundColor = self.tableView.separatorColor;
line;
});
The same in Swift (thanks, Dane Jordan, Yuichi Kato, Tony Merritt):
Swift 也是一样（感谢 Dane Jordan、Yuichi Kato、Tony Merritt）：
let px = 1 / UIScreen.main.scale
let frame = CGRect(x: 0, y: 0, width: self.tableView.frame.size.width, height: px)
let line = UIView(frame: frame)
self.tableView.tableHeaderView = line
line.backgroundColor = self.tableView.separatorColor
回答by Jason
I just got hit with this same problem and realised that the separator at the top is only displayed whilst scrolling the table.
我刚刚遇到了同样的问题，并意识到顶部的分隔符仅在滚动表格时显示。
What I then did was the following
然后我做的是以下
- In Interface Builder go to "Scroll View Size"
- Set the Content Insets of Top to 1
- 在界面生成器中转到“滚动视图大小”
- 将 Top 的 Content Insets 设置为 1
Alternatively in code you could do
或者在代码中你可以做
[tableView setContentInset:UIEdgeInsetsMake(1.0, 0.0, 0.0, 0.0)];
NOTE: This no longer works for iOS7 as the separators are no longer shown at all.
注意：这不再适用于 iOS7，因为根本不再显示分隔符。
回答by ddiego
I had the same problem and could not find an answer. So I added a line to the bottom of my table header.
我遇到了同样的问题，找不到答案。所以我在表格标题的底部添加了一行。
CGRect tableFrame = [[self view] bounds] ;
CGFloat headerHeight = 100;
UIView * headerView = [[UIView alloc] initWithFrame:CGRectMake(0,0,tableFrame.size.width, headerHeight)];
// Add stuff to my table header...
// Create separator
UIView *lineView = [[UIView alloc] initWithFrame:CGRectMake(0, headerHeight-1, tableFrame.size.width, 1)] ;
lineView.backgroundColor = [UIColor colorWithRed:224/255.0 green:224/255.0 blue:224/255.0 alpha:1.0];
[headerView addSubview:lineView];
self.tableView.tableHeaderView = headerView;
回答by fl034
I made a UITableView extension that displays a native style separator on top of the UITableView, while the table gets scrolled.
我制作了一个 UITableView 扩展，它在 UITableView 顶部显示一个原生样式分隔符，同时表格被滚动。
Here's the code (Swift 3)
这是代码（Swift 3）
fileprivate var _topSeparatorTag = 5432 // choose unused tag
extension UITableView {
fileprivate var _topSeparator: UIView? {
return superview?.subviews.filter { extension UITableView {
func addTableHeaderViewLine() {
self.tableHeaderView = {
let line = UIView(frame: CGRect(x: 0, y: 0, width: self.frame.size.width, height: 1 / UIScreen.main.scale))
line.backgroundColor = self.separatorColor
return line
}()
}
}
.tag == _topSeparatorTag }.first
}
override open var contentOffset: CGPoint {
didSet {
guard let topSeparator = _topSeparator else { return }
let shouldDisplaySeparator = contentOffset.y > 0
if shouldDisplaySeparator && topSeparator.alpha == 0 {
UIView.animate(withDuration: 0.15, animations: {
topSeparator.alpha = 1
})
} else if !shouldDisplaySeparator && topSeparator.alpha == 1 {
UIView.animate(withDuration: 0.25, animations: {
topSeparator.alpha = 0
})
}
}
}
// Adds a separator to the superview at the top of the table
// This needs the separator insets to be set on the tableView, not the cell itself
func showTopSeparatorWhenScrolled(_ enabled: Bool) {
if enabled {
if _topSeparator == nil {
let topSeparator = UIView()
topSeparator.backgroundColor = separatorColor?.withAlpha(newAlpha: 0.85) // because while scrolling, the other separators seem lighter
topSeparator.translatesAutoresizingMaskIntoConstraints = false
superview?.addSubview(topSeparator)
topSeparator.leftAnchor.constraint(equalTo: self.leftAnchor, constant: separatorInset.left).isActive = true
topSeparator.rightAnchor.constraint(equalTo: self.rightAnchor, constant: separatorInset.right).isActive = true
topSeparator.topAnchor.constraint(equalTo: self.topAnchor).isActive = true
let onePixelInPoints = CGFloat(1) / UIScreen.main.scale
topSeparator.heightAnchor.constraint(equalToConstant: onePixelInPoints).isActive = true
topSeparator.tag = _topSeparatorTag
topSeparator.alpha = 0
superview?.setNeedsLayout()
}
} else {
_topSeparator?.removeFromSuperview()
}
}
func removeSeparatorsOfEmptyCells() {
tableFooterView = UIView(frame: .zero)
}
}
To enable it, simply call tableView.showTopSeparatorWhenScrolled(true)after you set your delegatefor your UITableView
要启用它，只需拨打tableView.showTopSeparatorWhenScrolled(true)您设置后delegate您UITableView
回答by Vadim Nikolaev
Swift 4
斯威夫特 4
UIView *headerView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.tableView.frame.size.width, 1 / UIScreen.mainScreen.scale)];
UIView *topSeparator = [[UIView alloc] initWithFrame:CGRectMake(self.tableView.separatorInset.left, 0, self.tableView.frame.size.width - self.tableView.separatorInset.left - self.tableView.separatorInset.right, 1 / UIScreen.mainScreen.scale)];
topSeparator.backgroundColor = self.tableView.separatorColor;
[headerView addSubview:topSeparator];
self.tableView.tableHeaderView = headerView;
回答by Paul Mougin
In complement of Ortwin's answer, if you need to add some margin to your top separator to fit the separator inset, you have to embedded your top separator in another view :
作为Ortwin 的回答的补充，如果您需要为顶部分隔符添加一些边距以适合分隔符插图，则必须将顶部分隔符嵌入另一个视图中：
- (CGFloat)tableView:(UITableView *)tableView
heightForHeaderInSection:(NSInteger)section {
return 41;
}
- (UIView *)tableView:(UITableView *)tableView
viewForHeaderInSection:(NSInteger)section {
self.headerView = [[UIView alloc] init];
self.headerView.backgroundColor = [UIUtils colorForRGBColor:TIMESHEET_HEADERVIEW_COLOR];
self.separator = [[UIImageView alloc]initWithImage:[UIImage imageNamed:@"seperator.png"]];
self.separator.frame = CGRectMake(0,40,self.view.frame.size.width,1);
[self.headerView addSubview:self.separator];
return self.headerView;
}
Hope it helps.
希望能帮助到你。
回答by lzisko
I solved this by adding one extra line at the beginning of the table. Just have to set its height to 1, set its the text to empty, disable user interaction for it and in the whole code adjust the indexPath.row value.
我通过在表的开头添加一行来解决这个问题。只需将其高度设置为 1，将其文本设置为空，禁用用户交互并在整个代码中调整 indexPath.row 值。
回答by YaBoiSandeep
Add a separator between header view and first row :- In view for Header in section delegate method add a subview self.separator //@property (nonatomic, strong) UIImageView *separator;
在标题视图和第一行之间添加一个分隔符：- 在部分委托方法中的标题视图中添加一个子视图 self.separator //@property (nonatomic, strong) UIImageView *separator;
##代码##