Ios UICollectionView重新加载数据从不经过数据源
我试图在UICollectionView中显示数据,它与我在整个应用程序中所做的工作完全相同,但由于某些原因,在这种情况下它不起作用: 以下是理解问题所需的代码: SomeController:Ios UICollectionView重新加载数据从不经过数据源,ios,swift,uicollectionview,reloaddata,ios-multithreading,Ios,Swift,Uicollectionview,Reloaddata,Ios Multithreading,我试图在UICollectionView中显示数据,它与我在整个应用程序中所做的工作完全相同,但由于某些原因,在这种情况下它不起作用: 以下是理解问题所需的代码: SomeController: func showContactsView(sender: RoundButton) -> Void { DispatchQueue.main.async { self.someView = SomeView() self.view.
func showContactsView(sender: RoundButton) -> Void {
DispatchQueue.main.async {
self.someView = SomeView()
self.view.addSubview(self.someView)
self.someView.setSomeViewViewConstraints(container:
self.view)
self.someView.alpha = 0.0
self.someView.contactsCollectionView.delegate = self
self.someView.contactsCollectionView.dataSource = self
self.someView.tabControlCallbacks["contacts"] = self.searchContacts
}
}
//Collection Views Actions/Callbacks for selectContactsView
func searchContacts() -> Void {
let params : [String:Any] = [
"id" : "-1",
"name_begin" : ""
]
self.network?.get(......, callback: afterSearchContacts)
}
func afterSearchContacts() -> Void {
DispatchQueue.main.async {
self.contactsSearchResults.removeAll()
let usersData : [[String:Any]] = self.network?.lastResponse!["users"] as! [[String:Any]]
let groupsData : [[String:Any]] = self.network?.lastResponse!["groups"] as! [[String:Any]]
for userData in usersData {
self.contactsSearchResults.append(User(fromData: userData))
}
for groupData in groupsData {
self.contactsSearchResults.append(Group(fromData: groupData))
}
self.contactsView.contactsCollectionView.reloadData()
}
}
控制器初始化包含UICollectionView的视图。这部分由自动布局和约束处理,我对它没有任何问题。
它还从UIColleCtionViewDelegate和UICollectionViewDataSource继承:
class SomeController: UIViewController, UICollectionViewDataSource, UICollectionViewDelegate
视图位于collectionView中,由一个分段控件显示,该控件工作正常:
private func initCollectionViews() {
let layout = UICollectionViewFlowLayout()
layout.sectionInset = UIEdgeInsets(top: 10, left: 10, bottom: 10, right: 10)
layout.itemSize = CGSize(width: 50, height: 50)
contactsCollectionView = UICollectionView(frame: CGRect.zero, collectionViewLayout: layout)
contactsCollectionView.backgroundColor = UIColor.black.withAlphaComponent(0.6)
contactsCollectionView.showsVerticalScrollIndicator = false
contactsCollectionView.showsHorizontalScrollIndicator = false
contactsCollectionView.register(AModelCollectionViewCell.self, forCellWithReuseIdentifier: "ContactsSelectModelCell")
contactsCollectionView.translatesAutoresizingMaskIntoConstraints = false
// Constraints to add when view is set dynamically
contactsCollectionViewConstraints["leading"] = NSLayoutConstraint(item: contactsCollectionView, attribute: .leading, relatedBy: .equal, toItem: self, attribute: .leading, multiplier: 1.0, constant: 0.0)
contactsCollectionViewConstraints["trailing"] = NSLayoutConstraint(item: self, attribute: .trailing, relatedBy: .equal, toItem: contactsCollectionView, attribute: .trailing, multiplier: 1.0, constant: 0.0)
contactsCollectionViewConstraints["top"] = NSLayoutConstraint(item: tabControl, attribute: .bottom, relatedBy: .equal, toItem: contactsCollectionView, attribute: .top, multiplier: 1.0, constant: 0.0)
contactsCollectionViewConstraints["bottom"] = NSLayoutConstraint(item: self, attribute: .bottom, relatedBy: .equal, toItem: contactsCollectionView, attribute: .bottom, multiplier: 1.0, constant: 0.0)
}
分段控制的显示值发生变化:
func cleanViews() {
if self.contactsCollectionView.superview != nil {
self.contactsCollectionView.removeFromSuperview()
}
if self.favoritesCollectionView.superview != nil {
self.favoritesCollectionView.removeFromSuperview()
}
}
func bounce() {
self.cleanViews()
switch self.actualControl {
case -1:
break
case 0:
// Some code
case 1:
self.addSubview(self.contactsCollectionView)
for constraint in self.contactsCollectionViewConstraints {
self.addConstraint(constraint.value)
}
if let callback = self.tabControlCallbacks["contacts"]! {
callback()
}
default:
fatalError("Unknown control")
}
}
// Selectors UISegmentedControl
func valueChanged(sender: UISegmentedControl) {
if sender.selectedSegmentIndex == actualControl {
tabControl.isMomentary = true
sender.selectedSegmentIndex = -1
tabControl.isMomentary = false
}
actualControl = sender.selectedSegmentIndex
DispatchQueue.main.async {
self.bounce()
}
}
如您所见,我正在设置从控制器到视图的回调,以便对我的网络执行操作,并获取要在collectionView上显示的数据。以下是控制器中的方法:
func showContactsView(sender: RoundButton) -> Void {
DispatchQueue.main.async {
self.someView = SomeView()
self.view.addSubview(self.someView)
self.someView.setSomeViewViewConstraints(container:
self.view)
self.someView.alpha = 0.0
self.someView.contactsCollectionView.delegate = self
self.someView.contactsCollectionView.dataSource = self
self.someView.tabControlCallbacks["contacts"] = self.searchContacts
}
}
//Collection Views Actions/Callbacks for selectContactsView
func searchContacts() -> Void {
let params : [String:Any] = [
"id" : "-1",
"name_begin" : ""
]
self.network?.get(......, callback: afterSearchContacts)
}
func afterSearchContacts() -> Void {
DispatchQueue.main.async {
self.contactsSearchResults.removeAll()
let usersData : [[String:Any]] = self.network?.lastResponse!["users"] as! [[String:Any]]
let groupsData : [[String:Any]] = self.network?.lastResponse!["groups"] as! [[String:Any]]
for userData in usersData {
self.contactsSearchResults.append(User(fromData: userData))
}
for groupData in groupsData {
self.contactsSearchResults.append(Group(fromData: groupData))
}
self.contactsView.contactsCollectionView.reloadData()
}
}
重新加载的数据不起作用。以下是在解释哪个部件工作和哪个部件不工作之前,代表和数据源的方法:
//MARK: - UICollectionViewDataSource
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
switch self.contactsView.actualControl {
case 1:
if let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "ContactsSelectModelCell", for: indexPath) as? AModelCollectionViewCell {
cell.model = contactsSearchResults[indexPath.item]
cell.fillCell()
return cell
}
case 0:
//some Code
return cell
}
default:
print("Unknown cell type")
}
fatalError("Unknown cell type")
}
func numberOfSections(in collectionView: UICollectionView) -> Int {
return 1
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
let count = collectionView == contactsView.contactsCollectionView ? contactsSearchResults.count : favoritesSearchResults.count
return count
}
//MARK: - UICollectionViewFlowLayoutDelegate
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
return CGSize(width: 50.0, height: 50.0)
}
我有一个自定义的集合视图单元格,它正在处理其他集合视图,所以没有问题。在注册时,我还负责区分所有不同CollectionView的标识符。
在这种情况下,当我使用断点时,节中的项目数大于0,但当我在网络设置contactsSearchResult后在主线程中重新加载数据时,它永远不会通过collectionView cellForItemAt
有什么想法吗?对于那些读过这篇文章的人,我最后编写了我自己的CollectionView。像魔咒一样工作。当你说不工作时,到底发生了什么?它是否会转移到数据源方法?您能否打印Contacts CollectionView并查看它是否为零。还要检查其数据源是否为零当我说不工作时,我的意思是在这种情况下永远不会执行collectionView_collectionView:UICollectionView,cellForItemAt indexPath。ContactsCollectionView显然不是nil,与datasource相同。您确定它正在调用此行self.contactsView.ContactsCollectionView.reloadData吗?在那个之后,若你们把断点放在那个里,它会调用numberOfSections吗?我以前测试过这个,现在又测试了一次。不幸的是,情况就是这样。我不明白为什么collectionView\uCollectionView:UICollectionView,cellForItemAt indexPath不在numberOfSections更新之后调用。调用重载数据后,numberOfSections中的计数正好是6。将断点放在swift self行中,看看它是否在那个里。否则,请检查数据源名称是否拼写错误。还有,章节的数量和每个章节中的项目数量是多少?对吗?