Swift 添加无限循环中放置在uiscrollview上的图像视图
我下面的swift代码的目标是在uiscrollview中添加无数的图像视图。每次调用func add时,图像视图应在y轴上间隔200像素。我在下面添加了一个gif,显示了我希望通过循环实现的功能。我想我必须为此把[]放在酒吧里Swift 添加无限循环中放置在uiscrollview上的图像视图,swift,imageview,scrollview,infinite-loop,func,Swift,Imageview,Scrollview,Infinite Loop,Func,我下面的swift代码的目标是在uiscrollview中添加无数的图像视图。每次调用func add时,图像视图应在y轴上间隔200像素。我在下面添加了一个gif,显示了我希望通过循环实现的功能。我想我必须为此把[]放在酒吧里 您应该考虑使用 CuffVIEW视图>代码>。 通过这种方式,你可以添加无限多的细胞——可以是你的图像,也可以是你想要的任何东西。 您可以将单元格之间的距离设置为200px或任何其他值 每次点击add,您只需向用于CollectionView和CollectionVi
您应该考虑使用<代码> CuffVIEW视图>代码>。 通过这种方式,你可以添加无限多的细胞——可以是你的图像,也可以是你想要的任何东西。 您可以将单元格之间的距离设置为200px或任何其他值
每次点击add,您只需向用于CollectionView
和CollectionView.reloadData()
的数组添加一个新条目即可更新UI
希望对你有所帮助,祝你好运
class ViewController: UIViewController{
fileprivate var lastImage:UIImageView?
fileprivate var mainViewBootom:NSLayoutConstraint?
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .white
setupVIew()
}
override func viewDidAppear(_ animated: Bool) {
scrollView.contentSize = CGSize(width: view.frame.width, height: mainView.frame.height)
view.layoutIfNeeded()
}
//MARK: Components
let scrollView:UIScrollView = {
let sv = UIScrollView(frame: .zero)
return sv
}()
let mainView:UIView = {
let uv = UIView()
uv.backgroundColor = .white
return uv
}()
let btnAdd:UIButton = {
let btn = UIButton(type: .system)
btn.setTitle("Add", for: .normal)
return btn
}()
//MARK: Setup UI
func setupVIew() {
view.addSubview(scrollView)
view.addSubview(btnAdd)
scrollView.translatesAutoresizingMaskIntoConstraints = false
btnAdd.translatesAutoresizingMaskIntoConstraints = false
NSLayoutConstraint.activate([
btnAdd.centerXAnchor.constraint(equalTo: view.centerXAnchor),
btnAdd.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor, constant: -12),
btnAdd.widthAnchor.constraint(equalToConstant: 100),
btnAdd.heightAnchor.constraint(equalToConstant: 45),
scrollView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
scrollView.trailingAnchor.constraint(equalTo: view.trailingAnchor),
scrollView.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor),
scrollView.bottomAnchor.constraint(equalTo: btnAdd.topAnchor , constant: -12),
])
btnAdd.addTarget(self, action: #selector(didClickedAdd), for: .touchUpInside)
scrollView.addSubview(mainView)
mainView.translatesAutoresizingMaskIntoConstraints = false
NSLayoutConstraint.activate([
mainView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
mainView.trailingAnchor.constraint(equalTo: view.trailingAnchor),
mainView.topAnchor.constraint(equalTo: scrollView.topAnchor),
])
let imgView = UIImageView(frame: CGRect(x: 0, y: 0, width: 150, height: 100))
imgView.backgroundColor = .red
mainView.addSubview(imgView)
imgView.translatesAutoresizingMaskIntoConstraints = false
imgView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
imgView.widthAnchor.constraint(equalToConstant: 150).isActive = true
imgView.heightAnchor.constraint(equalToConstant: 100).isActive = true
if lastImage != nil {
imgView.topAnchor.constraint(equalTo: lastImage!.bottomAnchor , constant: 20).isActive = true
}else{
imgView.topAnchor.constraint(equalTo: mainView.topAnchor , constant: 12).isActive = true
}
lastImage = imgView
mainViewBootom = mainView.bottomAnchor.constraint(equalTo: lastImage!.bottomAnchor , constant: 12)
mainViewBootom!.isActive = true
}
@objc func didClickedAdd(){
let imgView = UIImageView(frame: CGRect(x: 0, y: 0, width: 150, height: 100))
imgView.backgroundColor = .red
mainView.addSubview(imgView)
imgView.translatesAutoresizingMaskIntoConstraints = false
imgView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
imgView.widthAnchor.constraint(equalToConstant: 150).isActive = true
imgView.heightAnchor.constraint(equalToConstant: 100).isActive = true
if lastImage != nil {
imgView.topAnchor.constraint(equalTo: lastImage!.bottomAnchor , constant: 20).isActive = true
}else{
imgView.topAnchor.constraint(equalTo: mainView.topAnchor , constant: 12).isActive = true
}
lastImage = imgView
mainView.removeConstraint(mainViewBootom!)
mainViewBootom = mainView.bottomAnchor.constraint(equalTo: lastImage!.bottomAnchor , constant: 12)
mainViewBootom!.isActive = true
view.layoutIfNeeded()
scrollView.contentSize = CGSize(width: view.frame.width, height: mainView.frame.height)
view.layoutIfNeeded()
}
}
`图像视图怎么可能“无穷无尽”?在我看来,您想要的只是在点击
add
时添加一个图像视图。这是正确的,当用户点击1个按钮时,它会添加一个uiimageview。那么“无止境”或“无限循环”部分是什么呢?我的意思是,“1”几乎是“无限”的反面。是哪一个?
class ViewController: UIViewController{
fileprivate var lastImage:UIImageView?
fileprivate var mainViewBootom:NSLayoutConstraint?
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .white
setupVIew()
}
override func viewDidAppear(_ animated: Bool) {
scrollView.contentSize = CGSize(width: view.frame.width, height: mainView.frame.height)
view.layoutIfNeeded()
}
//MARK: Components
let scrollView:UIScrollView = {
let sv = UIScrollView(frame: .zero)
return sv
}()
let mainView:UIView = {
let uv = UIView()
uv.backgroundColor = .white
return uv
}()
let btnAdd:UIButton = {
let btn = UIButton(type: .system)
btn.setTitle("Add", for: .normal)
return btn
}()
//MARK: Setup UI
func setupVIew() {
view.addSubview(scrollView)
view.addSubview(btnAdd)
scrollView.translatesAutoresizingMaskIntoConstraints = false
btnAdd.translatesAutoresizingMaskIntoConstraints = false
NSLayoutConstraint.activate([
btnAdd.centerXAnchor.constraint(equalTo: view.centerXAnchor),
btnAdd.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor, constant: -12),
btnAdd.widthAnchor.constraint(equalToConstant: 100),
btnAdd.heightAnchor.constraint(equalToConstant: 45),
scrollView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
scrollView.trailingAnchor.constraint(equalTo: view.trailingAnchor),
scrollView.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor),
scrollView.bottomAnchor.constraint(equalTo: btnAdd.topAnchor , constant: -12),
])
btnAdd.addTarget(self, action: #selector(didClickedAdd), for: .touchUpInside)
scrollView.addSubview(mainView)
mainView.translatesAutoresizingMaskIntoConstraints = false
NSLayoutConstraint.activate([
mainView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
mainView.trailingAnchor.constraint(equalTo: view.trailingAnchor),
mainView.topAnchor.constraint(equalTo: scrollView.topAnchor),
])
let imgView = UIImageView(frame: CGRect(x: 0, y: 0, width: 150, height: 100))
imgView.backgroundColor = .red
mainView.addSubview(imgView)
imgView.translatesAutoresizingMaskIntoConstraints = false
imgView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
imgView.widthAnchor.constraint(equalToConstant: 150).isActive = true
imgView.heightAnchor.constraint(equalToConstant: 100).isActive = true
if lastImage != nil {
imgView.topAnchor.constraint(equalTo: lastImage!.bottomAnchor , constant: 20).isActive = true
}else{
imgView.topAnchor.constraint(equalTo: mainView.topAnchor , constant: 12).isActive = true
}
lastImage = imgView
mainViewBootom = mainView.bottomAnchor.constraint(equalTo: lastImage!.bottomAnchor , constant: 12)
mainViewBootom!.isActive = true
}
@objc func didClickedAdd(){
let imgView = UIImageView(frame: CGRect(x: 0, y: 0, width: 150, height: 100))
imgView.backgroundColor = .red
mainView.addSubview(imgView)
imgView.translatesAutoresizingMaskIntoConstraints = false
imgView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
imgView.widthAnchor.constraint(equalToConstant: 150).isActive = true
imgView.heightAnchor.constraint(equalToConstant: 100).isActive = true
if lastImage != nil {
imgView.topAnchor.constraint(equalTo: lastImage!.bottomAnchor , constant: 20).isActive = true
}else{
imgView.topAnchor.constraint(equalTo: mainView.topAnchor , constant: 12).isActive = true
}
lastImage = imgView
mainView.removeConstraint(mainViewBootom!)
mainViewBootom = mainView.bottomAnchor.constraint(equalTo: lastImage!.bottomAnchor , constant: 12)
mainViewBootom!.isActive = true
view.layoutIfNeeded()
scrollView.contentSize = CGSize(width: view.frame.width, height: mainView.frame.height)
view.layoutIfNeeded()
}
}