在if-else

Question

当我将单元格返回到if-else之外时遇到问题，它会给我一个错误“使用未解析的标识符'单元格'”。这是我的代码：

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

    if let feedItem = feeds.objectAtIndex(UInt(indexPath.row)) as? FeedsDataModel {
        if feedItem.media_url != "" {
            let cell = tableView.dequeueReusableCellWithIdentifier("FeedsTableWithImgCell", forIndexPath: indexPath) as! FeedsTableViewWithImageCell
            cell.setupCellWithFeedItem()
        }
        else {
            let cell = tableView.dequeueReusableCellWithIdentifier("FeedsTableWithoutImgCell", forIndexPath: indexPath) as! FeedsTableViewWithoutImageCell
            cell.setupCellWithFeedItem()
        }

        return cell
    }
}

Answer 1

使用

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

if let feedItem = feeds.objectAtIndex(UInt(indexPath.row)) as? FeedsDataModel {
    if feedItem.media_url != "" {
        let cell = tableView.dequeueReusableCellWithIdentifier("FeedsTableWithImgCell", forIndexPath: indexPath) as! FeedsTableViewWithImageCell
        cell.setupCellWithFeedItem()
        return cell
    }
    else {
        let cell = tableView.dequeueReusableCellWithIdentifier("FeedsTableWithoutImgCell", forIndexPath: indexPath) as! FeedsTableViewWithoutImageCell
        cell.setupCellWithFeedItem()
        return cell
    }


}
}

<强>更新

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

  let cell: FeedsTableViewWithImageCell

if let feedItem = feeds.objectAtIndex(UInt(indexPath.row)) as? FeedsDataModel {
    if feedItem.media_url != "" {
         cell = tableView.dequeueReusableCellWithIdentifier("FeedsTableWithImgCell", forIndexPath: indexPath) as! FeedsTableViewWithImageCell
        cell.setupCellWithFeedItem()

    }
    else {
         cell = tableView.dequeueReusableCellWithIdentifier("FeedsTableWithoutImgCell", forIndexPath: indexPath) as! FeedsTableViewWithoutImageCell
        cell.setupCellWithFeedItem()

    }


}
     return cell
}

编辑＆amp;更新

   func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

if let feedItem = feeds.objectAtIndex(UInt(indexPath.row)) as? FeedsDataModel {
    var cell:FeedsTableViewWithImageCell!
    if feedItem.media_url != "" {
        cell = tableView.dequeueReusableCellWithIdentifier("FeedsTableWithImgCell", forIndexPath: indexPath) as! FeedsTableViewWithImageCell
        cell.setupCellWithFeedItem()
    }
    else {
       let cell1 = tableView.dequeueReusableCellWithIdentifier("FeedsTableWithoutImgCell", forIndexPath: indexPath) as! FeedsTableViewWithoutImageCell
        cell1.setupCellWithFeedItem()
         return cell1
    }

    return cell
}
}

Answer 2

单元格必须是范围内的全局变量。

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

    if let feedItem = feeds.objectAtIndex(UInt(indexPath.row)) as? FeedsDataModel {
        var cell:FeedsTableViewWithImageCell!
        if feedItem.media_url != "" {
            cell = tableView.dequeueReusableCellWithIdentifier("FeedsTableWithImgCell", forIndexPath: indexPath) as! FeedsTableViewWithImageCell
            cell.setupCellWithFeedItem()
        }
        else {
            cell = tableView.dequeueReusableCellWithIdentifier("FeedsTableWithoutImgCell", forIndexPath: indexPath) as! FeedsTableViewWithoutImageCell
            cell.setupCellWithFeedItem()
        }

        return cell
    }
}

Answer 3

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
     var cell: FeedsTableViewWithImageCell?
    if let feedItem = feeds.objectAtIndex(UInt(indexPath.row)) as? FeedsDataModel {
        if feedItem.media_url != "" {
            cell = tableView.dequeueReusableCellWithIdentifier("FeedsTableWithImgCell", forIndexPath: indexPath) as! FeedsTableViewWithImageCell
            cell.setupCellWithFeedItem()
        }
        else {
            cell = tableView.dequeueReusableCellWithIdentifier("FeedsTableWithoutImgCell", forIndexPath: indexPath) as! FeedsTableViewWithoutImageCell
            cell.setupCellWithFeedItem()
        }


    }
return cell!
}

Answer 4

写下面的代码行。你的问题将得到解决。

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
    var cell: UITableViewCell?
    if let feedItem = feeds.objectAtIndex(UInt(indexPath.row)) as? FeedsDataModel {
        if feedItem.media_url != "" {
            cell = tableView.dequeueReusableCellWithIdentifier("FeedsTableWithImgCell", forIndexPath: indexPath) as! FeedsTableViewWithImageCell
            cell.setupCellWithFeedItem()
        }
        else {
            cell = tableView.dequeueReusableCellWithIdentifier("FeedsTableWithoutImgCell", forIndexPath: indexPath) as! FeedsTableViewWithoutImageCell
            cell.setupCellWithFeedItem()
        }
    }

    return cell!
}

Answer 5

cell范围内声明的if变量。在此范围之外不可见。您有两种选择如何解决它：

1. 在同一范围内返回cell

   if let feedItem = feeds.objectAtIndex(UInt(indexPath.row)) as? FeedsDataModel {
       if feedItem.media_url != "" {
           let cell = tableView.dequeueReusableCellWithIdentifier("FeedsTableWithImgCell", forIndexPath: indexPath) as! FeedsTableViewWithImageCell
           cell.setupCellWithFeedItem()
           return cell
       }
       else {
           let cell = tableView.dequeueReusableCellWithIdentifier("FeedsTableWithoutImgCell", forIndexPath: indexPath) as! FeedsTableViewWithoutImageCell
           cell.setupCellWithFeedItem()
           return cell
       }
   }
   

2. 在if范围

   之前声明变量

   var cell: FeedsTableViewWithImageCell?
   if let feedItem = feeds.objectAtIndex(UInt(indexPath.row)) as? FeedsDataModel {
       if feedItem.media_url != "" {
           cell = tableView.dequeueReusableCellWithIdentifier("FeedsTableWithImgCell", forIndexPath: indexPath) as! FeedsTableViewWithImageCell
           cell.setupCellWithFeedItem()
       }
       else {
           cell = tableView.dequeueReusableCellWithIdentifier("FeedsTableWithoutImgCell", forIndexPath: indexPath) as! FeedsTableViewWithoutImageCell
           cell.setupCellWithFeedItem()
       }
   }
   return cell