我做了一个自定义 UITableViewRowAction。现在我想添加一个图像而不是文本。我知道这是可能的,但不知道该怎么做。你们中有人知道如何在 Swift 中做到这一点并愿意帮助我吗?感谢您的回答!
9 回答
iOS 11.0
迅速
Apple 引入了灵活的方式来声明行操作,带来了很大的好处。
extension ViewController: UITableViewDelegate {
func tableView(_ tableView: UITableView, trailingSwipeActionsConfigurationForRowAt indexPath: IndexPath) -> UISwipeActionsConfiguration? {
let askAction = UIContextualAction(style: .normal, title: nil) { action, view, complete in
print("Ask!")
complete(true)
}
// here set your image and background color
askAction.image = IMAGE
askAction.backgroundColor = .darkGray
let blockAction = UIContextualAction(style: .destructive, title: "Block") { action, view, complete in
print("Block")
complete(true)
}
return UISwipeActionsConfiguration(actions: [blockAction, askAction])
}
func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {
cell.textLabel?.text = "row: \(indexPath.row)"
}
}
例子:
iOS 8.0
您需要将 UIImage 设置为行操作的 backgroundColor,具体通过:
迅速:
UIColor(patternImage: UIImage(named: "IMAGE_NAME"))
目标-C:
[UIColor colorWithPatternImage:[UIImage imageNamed:@"IMAGE_NAME"]];
斯威夫特 4 (iOS 11+):
iOS 11 现在(仅)支持在操作按钮中显示图像。您只需在表视图委托对象中初始化一个 UISwipeActionsConfiguration 对象:
extension MyTableViewController:UITableViewDelegate {
func tableView(_ tableView: UITableView, trailingSwipeActionsConfigurationForRowAt indexPath: IndexPath) -> UISwipeActionsConfiguration? {
let deleteAction = UIContextualAction(style: .normal, title: nil, handler: { (ac:UIContextualAction, view:UIView, success:(Bool) -> Void) in
debugPrint("Delete tapped")
success(true)
})
deleteAction.image = UIImage(named: "icon_delete.png")
deleteAction.backgroundColor = UIColor.red
return UISwipeActionsConfiguration(actions: [deleteAction])
}
}
我制作了这个简单的 UITableViewRowAction 类别,以便为我的操作设置图标。您可以设置图像、背景颜色、单元格高度(管理动态单元格)和图标大小百分比。
extension UITableViewRowAction {
func setIcon(iconImage: UIImage, backColor: UIColor, cellHeight: CGFloat, iconSizePercentage: CGFloat)
{
let iconHeight = cellHeight * iconSizePercentage
let margin = (cellHeight - iconHeight) / 2 as CGFloat
UIGraphicsBeginImageContextWithOptions(CGSize(width: cellHeight, height: cellHeight), false, 0)
let context = UIGraphicsGetCurrentContext()
backColor.setFill()
context!.fill(CGRect(x:0, y:0, width:cellHeight, height:cellHeight))
iconImage.draw(in: CGRect(x: margin, y: margin, width: iconHeight, height: iconHeight))
let actionImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
self.backgroundColor = UIColor.init(patternImage: actionImage!)
}
}
class TableViewRowAction: UITableViewRowAction
{
var image: UIImage?
func _setButton(button: UIButton)
{
if let image = image, let titleLabel = button.titleLabel
{
let labelString = NSString(string: titleLabel.text!)
let titleSize = labelString.sizeWithAttributes([NSFontAttributeName: titleLabel.font])
button.tintColor = UIColor.whiteColor()
button.setImage(image.imageWithRenderingMode(.AlwaysTemplate), forState: .Normal)
button.imageEdgeInsets.right = -titleSize.width
}
}
}
func tableView(tableView: UITableView, editActionsForRowAtIndexPath indexPath: NSIndexPath) -> [UITableViewRowAction]?
{
let delete = TableViewRowAction(style: UITableViewRowActionStyle.Default, title: " ") { action, indexPath in }
delete.image = UIImage(named: "trashImg")
let sharing = TableViewRowAction(style: UITableViewRowActionStyle.Default, title: " ") { action, indexPath in }
sharing.backgroundColor = UIColor.lightGrayColor()
sharing.image = UIImage(named: "sharingImg")
return [delete, sharing]
}
我只是实现了更好的版本https://stackoverflow.com/a/48122210 1. 在大多数情况下,单元格的高度和自定义滑动部分的宽度是不同的,你必须在你的函数中计算这个 2. 图像可以有不同的大小比正方形,所以你必须计算比例,而不仅仅是高度。所以,用我的修复代码
func setIcon(iconImage: UIImage, backColor: UIColor, cellHeight: CGFloat, customSwipPartWidth: CGFloat, iconSizePercentage: CGFloat) {
let iconWidth = customSwipPartWidth * iconSizePercentage
let iconHeight = iconImage.size.height / iconImage.size.width * iconWidth
let marginY = (cellHeight - iconHeight) / 2 as CGFloat
let marginX = (customSwipPartWidth - iconWidth) / 2 as CGFloat
UIGraphicsBeginImageContextWithOptions(CGSize(width: customSwipPartWidth, height: cellHeight), false, 0)
let context = UIGraphicsGetCurrentContext()
backColor.setFill()
context!.fill(CGRect(x:0, y:0, width:customSwipPartWidth, height:cellHeight))
iconImage.draw(in: CGRect(x: marginX, y: marginY, width: iconWidth, height: iconHeight))
let actionImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
self.backgroundColor = UIColor.init(patternImage: actionImage!)
}
对于那些想要创造这种效果的人;
我创建了一个扩展UISwipeActionsConfiguration
,您可以在没有任何第三方库的情况下使用它。基本上,这个想法是从图像和文本创建一个属性字符串,并将其设置为标签并从该标签创建一个图像。并将其附加到UIContextualAction
' 的image
属性。
extension UISwipeActionsConfiguration {
public static func makeTitledImage(
image: UIImage?,
title: String,
textColor: UIColor = .white,
font: UIFont = .systemFont(ofSize: 14),
size: CGSize = .init(width: 50, height: 50)
) -> UIImage? {
/// Create attributed string attachment with image
let attachment = NSTextAttachment()
attachment.image = image
let imageString = NSAttributedString(attachment: attachment)
/// Create attributed string with title
let text = NSAttributedString(
string: "\n\(title)",
attributes: [
.foregroundColor: textColor,
.font: font
]
)
/// Merge two attributed strings
let mergedText = NSMutableAttributedString()
mergedText.append(imageString)
mergedText.append(text)
/// Create label and append that merged attributed string
let label = UILabel(frame: CGRect(x: 0, y: 0, width: size.width, height: size.height))
label.textAlignment = .center
label.numberOfLines = 2
label.attributedText = mergedText
/// Create image from that label
let renderer = UIGraphicsImageRenderer(bounds: label.bounds)
let image = renderer.image { rendererContext in
label.layer.render(in: rendererContext.cgContext)
}
/// Convert it to UIImage and return
if let cgImage = image.cgImage {
return UIImage(cgImage: cgImage, scale: UIScreen.main.scale, orientation: .up)
}
return nil
}
}
你可以这样使用它;
public func tableView(
_ tableView: UITableView,
trailingSwipeActionsConfigurationForRowAt indexPath: IndexPath
) -> UISwipeActionsConfiguration?
{
let deleteAction = UIContextualAction(
style: .normal,
title: nil,
handler: { [weak self] (_, _, success: (Bool) -> Void) in
success(true)
print("Your action in here")
}
)
deleteAction.image = UISwipeActionsConfiguration.makeTitledImage(
image: UIImage(named: "delete_icon"),
title: "Delete")
)
deleteAction.backgroundColor = .orange
return UISwipeActionsConfiguration(actions: [deleteAction])
}
我的变体尝试使用 UImageView 的 contentMode 行为,当这还不够时,我发现一些 Core Geometry Rect 方法有很好的用途,因为它们将目标框架保持在单元框架内的中心。使用眼睛测试,似乎刷卡消除了我正常单元格宽度的一半,所以这就是神奇数字出现的地方。
斯威夫特 3.0
extension UITableViewRowAction {
func setIcon(iconImage: UIImage, backColor: UIColor, cellHeight: CGFloat, cellWidth:CGFloat) ///, iconSizePercentage: CGFloat)
{
let cellFrame = CGRect(origin: .zero, size: CGSize(width: cellWidth*0.5, height: cellHeight))
let imageFrame = CGRect(x:0, y:0,width:iconImage.size.width, height: iconImage.size.height)
let insetFrame = cellFrame.insetBy(dx: ((cellFrame.size.width - imageFrame.size.width) / 2), dy: ((cellFrame.size.height - imageFrame.size.height) / 2))
let targetFrame = insetFrame.offsetBy(dx: -(insetFrame.width / 2.0), dy: 0.0)
let imageView = UIImageView(frame: imageFrame)
imageView.image = iconImage
imageView.contentMode = .left
guard let resizedImage = imageView.image else { return }
UIGraphicsBeginImageContextWithOptions(CGSize(width: cellWidth, height: cellHeight), false, 0)
guard let context = UIGraphicsGetCurrentContext() else { return }
backColor.setFill()
context.fill(CGRect(x:0, y:0, width:cellWidth, height:cellHeight))
resizedImage.draw(in: CGRect(x:(targetFrame.origin.x / 2), y: targetFrame.origin.y, width:targetFrame.width, height:targetFrame.height))
guard let actionImage = UIGraphicsGetImageFromCurrentImageContext() else { return }
UIGraphicsEndImageContext()
self.backgroundColor = UIColor.init(patternImage: actionImage)
}
}
用法:来自 tableview 委托的 editActions... 方法。
let cellHeight = (self.tableView(tableView, cellForRowAt: indexPath)).frame.size.height
let cellWidth = (self.tableView(tableView, cellForRowAt: indexPath)).frame.size.width
let favorite = UITableViewRowAction(style: .normal, title: nil) { action, index in
//perform action
debugPrint("Test")
}
favorite.setIcon(iconImage: #imageLiteral(resourceName: "favorite"), backColor: .green, cellHeight: cellHeight, cellWidth:cellWidth)
delActions.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"delete.png"]];
基本图案颜色方法的问题是您的图像需要与操作按钮具有相同的大小,或者至少在底部有一些更平坦的背景以防止图像重复(即使它将被锚定在顶部,这不是很好)。
我必须处理动态高度单元格,所以我实现了以下内容:
- (UIColor *)backgroundImageForActionAtIndexPath:(NSIndexPath *)indexPath withImage:(UIImage *)image tintColor:(UIColor *)tintColor backgroundColor:(UIColor *)backgrounfColor expectedWith:(CGFloat)width {
//
CGRect cellFrame = [self.tableView rectForRowAtIndexPath:indexPath];
CGSize expectedSize = CGSizeMake(width, cellFrame.size.height);
UIGraphicsBeginImageContextWithOptions(expectedSize, NO, 0.0);
CGContextRef ctx = UIGraphicsGetCurrentContext ();
if (ctx) {
// set the background
CGContextSetFillColorWithColor(ctx, backgrounfColor.CGColor);
CGRect fillRect = CGRectZero;
fillRect.size = expectedSize;
CGContextFillRect(ctx, fillRect);
// put the image
CGContextSetFillColorWithColor(ctx, tintColor.CGColor);
CGRect rect = CGRectMake((expectedSize.width - image.size.width) / 2., (expectedSize.height - image.size.height) / 2., image.size.width, image.size.height);
[image drawInRect:rect];
}
UIImage * newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return [UIColor colorWithPatternImage:newImage];
}
您仍然需要设置 expectedWidth 以使其与您在操作标题中放置的空标签相匹配。例如:@" " -> 64.f
正如您使用这种方法所看到的,您可以在代码中而不是在艺术品本身中设置按钮的背景和色调颜色。