我在应用程序的主视图 Controller 上有一个带有 UIButton 的 Collection View ,当用户更改其状态时需要对其进行更改。
我正在使用 Firebase 观察者值,因此当值发生变化时,它会立即改变按钮颜色和图像。
问题是当我更改第二个单元格的值并向前更改时,它会将所有单元格更改为。
为了更好地理解,我添加了图片:
This is the cells before changing the value of the second one.
And this is the what happens after I changed only the second cell values on firebase
如您所见,它也会影响第一个单元格。 使用事务 block 从另一个 View Controller 更改此观察者的值。
我在谷歌上搜索了这个问题,发现了类似的问题,但没有一个答案可以解决这个问题。
这是 Collection View 的代码:
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "group_card_cell", for: indexPath) as! HomeGroupCollectionViewCell
cell.prepareForReuse()
cell.groupName.text = groups[indexPath.row].name
cell.groupSchedule.text = "\(groups[indexPath.row].day!), Around \(groups[indexPath.row].time!)"
cell.cardMoreButtonRef.addTarget(self, action: #selector(buttonAction), for: .touchUpInside)
cell.cardMoreButtonRef.tag = indexPath.row
//Changing card attending color and value:
self.ref.child("Groups").child(groups[indexPath.row].uid!).child("groupFriendsList").child(currentUser!.uid).observe(.value) { (snapshot) in
guard let value = snapshot.value as? String else {return}
switch value{
case "Going":
cell.groupAttendButtonRef.backgroundColor = UIColor.init(named: "GoingColor")
cell.groupAttendButtonRef.setImage(UIImage(named: "icons8-checkmark_filled"), for: .normal)
case "Not Going":
cell.groupAttendButtonRef.backgroundColor = UIColor.init(named: "NotGoingColor")
cell.groupAttendButtonRef.setImage(UIImage(named: "icons8-delete_sign_filled"), for: .normal)
case "Maybe":
cell.groupAttendButtonRef.backgroundColor = UIColor.init(named: "MaybeColor")
cell.groupAttendButtonRef.setImage(UIImage(named: "icons8-minus_math_filled"), for: .normal)
default:
cell.groupAttendButtonRef.backgroundColor = UIColor.init(named: "MaybeColor")
cell.groupAttendButtonRef.setImage(UIImage(named: "icons8-minus_math_filled"), for: .normal)
}
}
return cell
}
提前致谢!
最佳答案
您是否尝试过在 Firebase 事件回调中检索特定 indexPath 的 cell
?
您可以使用 -
let specificCell = collectionView.cellForItem(at: IndexPath (row: row, section: section))
获取仅基于 indexPath 的单元格
或者您可以使用重用标识符获取它 -
let idpath = IndexPath(row: indexPath.row-1, section: indexPath.section)
let specificCell = collectionView.dequeueReusableCell(withReuseIdentifier: "cell", for: idpath)
一旦您获得了单元格,您就可以相应地设置该单元格的 groupAttendButtonRef
。
关于ios - Firebase 观察者值影响所有 Collection View 单元格,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/53172249/