如何以编程方式向 UITableViewCell swift 内的 UIStackView 添加约束?
How to add constraints to UIStackView inside of a UITableViewCell swift programmatically?
我有一个函数可以创建一个数组 UIStackViews
,其中包含 UIButtons
:
func generateStackViews() -> [UIStackView] {
var stackViewArray = [UIStackView]()
let finalButtonArray = generateButtons()
for buttons in finalButtonArray{
stackViewArray.append(createStackView(subViews: buttons))
}
return stackViewArray
}
然后我将该数组添加到 tableViewCell
:
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "First")!
cell.contentView.addSubview(generateStackViews()[indexPath.row])
return cell
}
一切正常,但当我尝试添加约束以将 stackViews
固定到单元格时,出现此错误:
failure in -[UITableViewCell _layoutEngine_didAddLayoutConstraint:roundingAdjustment:mutuallyExclusiveConstraints:]
我尝试在创建 stackViews
的函数中添加约束,并在 cellForRowAt
函数中尝试将其固定到 contentView
、单元格和 tableView
, 但都不起作用,我收到了相同的错误消息。
我的逻辑哪里出错了?
调用此方法以编程方式添加约束。
func addSubviewWithConstraint(to parentView: UIView, and childView: UIView, top:CGFloat, bottom:CGFloat, leading:CGFloat, trailing:CGFloat) {
parentView.addSubview(childView)
//Below line tells the view to not use AutoResizing
childView.translatesAutoresizingMaskIntoConstraints = false
// set top constraint
let topConstraint = NSLayoutConstraint(item: childView, attribute: .top, relatedBy: .equal, toItem: parentView, attribute: .top, multiplier: 1, constant: top)
// set Bottom constraint
let bottomConstraint = NSLayoutConstraint(item: childView, attribute: .bottom, relatedBy: .equal, toItem: parentView, attribute: .bottom, multiplier: 1, constant: bottom)
// set leading constraint
let leadingConstraint = NSLayoutConstraint(item: childView, attribute: .leading, relatedBy: .equal, toItem: parentView, attribute: .leading, multiplier: 1, constant: leading)
// set Bottom constraint
let trailingConstraint = NSLayoutConstraint(item: childView, attribute: .trailing, relatedBy: .equal, toItem: parentView, attribute: .trailing, multiplier: 1, constant: trailing)
//Add all constraints to parentView
parentView.addConstraint(topConstraint)
parentView.addConstraint(bottomConstraint)
parentView.addConstraint(leadingConstraint)
parentView.addConstraint(trailingConstraint)
}
然后像这样调用上面的方法
self.addSubviewWithConstraint(to: cell.contenetView, and: stackView, top: 0, bottom: 0, leading: 0, trailing: 0)
我有一个函数可以创建一个数组 UIStackViews
,其中包含 UIButtons
:
func generateStackViews() -> [UIStackView] {
var stackViewArray = [UIStackView]()
let finalButtonArray = generateButtons()
for buttons in finalButtonArray{
stackViewArray.append(createStackView(subViews: buttons))
}
return stackViewArray
}
然后我将该数组添加到 tableViewCell
:
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "First")!
cell.contentView.addSubview(generateStackViews()[indexPath.row])
return cell
}
一切正常,但当我尝试添加约束以将 stackViews
固定到单元格时,出现此错误:
failure in -[UITableViewCell _layoutEngine_didAddLayoutConstraint:roundingAdjustment:mutuallyExclusiveConstraints:]
我尝试在创建 stackViews
的函数中添加约束,并在 cellForRowAt
函数中尝试将其固定到 contentView
、单元格和 tableView
, 但都不起作用,我收到了相同的错误消息。
我的逻辑哪里出错了?
调用此方法以编程方式添加约束。
func addSubviewWithConstraint(to parentView: UIView, and childView: UIView, top:CGFloat, bottom:CGFloat, leading:CGFloat, trailing:CGFloat) {
parentView.addSubview(childView)
//Below line tells the view to not use AutoResizing
childView.translatesAutoresizingMaskIntoConstraints = false
// set top constraint
let topConstraint = NSLayoutConstraint(item: childView, attribute: .top, relatedBy: .equal, toItem: parentView, attribute: .top, multiplier: 1, constant: top)
// set Bottom constraint
let bottomConstraint = NSLayoutConstraint(item: childView, attribute: .bottom, relatedBy: .equal, toItem: parentView, attribute: .bottom, multiplier: 1, constant: bottom)
// set leading constraint
let leadingConstraint = NSLayoutConstraint(item: childView, attribute: .leading, relatedBy: .equal, toItem: parentView, attribute: .leading, multiplier: 1, constant: leading)
// set Bottom constraint
let trailingConstraint = NSLayoutConstraint(item: childView, attribute: .trailing, relatedBy: .equal, toItem: parentView, attribute: .trailing, multiplier: 1, constant: trailing)
//Add all constraints to parentView
parentView.addConstraint(topConstraint)
parentView.addConstraint(bottomConstraint)
parentView.addConstraint(leadingConstraint)
parentView.addConstraint(trailingConstraint)
}
然后像这样调用上面的方法
self.addSubviewWithConstraint(to: cell.contenetView, and: stackView, top: 0, bottom: 0, leading: 0, trailing: 0)