ios - 从 Parse 下载后使用图像或文本进行排序

Question

我有一个 tableView，每个单元格中包含三个图像，其中显示我的帖子类中的所有图像。所以我下载所有图像，然后在将它们放入单元格中时将它们除以 3!因此，下载时它不会在每个单元格中显示相同的图像 3 次...

有点令人困惑，但如果我向您展示我的代码，您可能会理解它如何更好地工作!

但无论如何，我现在想做的事情是相同的，但带有文本，因此在单元格中，根据下载的内容，它将正常显示图像，或者如果它们是文本，它将显示文本而不是图片!!

// HERE'S HOW I SORT THE 3 IMAGES WHEN DOWNLOADED (CellForRowAtIndexPath)

if post.dataType == 1 
{ 
for imageView in cell.threeImages { 
imageView.image = UIImage(named: "ImagePlaceHolder") 

if counter < posts.count{ 
imageView.hidden = false 
let imagePost = posts[counter++].image 
imagePost!.getDataInBackgroundWithBlock { (data:NSData?, error:NSError?) -> Void in 
if error == nil { 
if let imageData = data { 
imageView.image = UIImage(data: imageData) 
} 

} 
} 
} else { 
imageView.hidden = true 
}



// AND HERE'S HOW I SORT THEM / DIVIDE THEM BY 3 SO THEY'RE NOT ALL THE SAME FOR EACH ROW.

func roundUp(value: Double) -> Int {
    if value == Double(Int(value)) {
        return Int(value)
    } else if value < 0 {
        return Int(value)
    } else {
        return Int(value) + 1
    }
}

func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int
{

        return = roundUp(Double(posts.count) / 3.0) 


}

这是模拟器上现在的样子，下载所有图像后，它还从解析中下载 1 个文本列:[![在此处输入图像描述][1]][1]

现在，当我在这里尝试此代码后:

//IMAGES

    if post.dataType == 1 
    { 
    //Images 
    for imageView in cell.threeImages { 
    imageView.image = UIImage(named: "ImagePlaceHolder") 

    if counter < posts.count{ 

    imageView.hidden = false 

    let imagePost = posts[counter++].image 
    imagePost!.getDataInBackgroundWithBlock { (data:NSData?, error:NSError?) -> Void in 
    if error == nil { 
    if let imageData = data { 
    imageView.image = UIImage(data: imageData) 

//TEXT
    for textHide in cell.threeLabels{ 
    textHide.hidden = true 
    }}}} } else { 
    imageView.hidden = true 
    } 

我得到的结果几乎就在那里:

[![在此处输入图像描述][2]][2]

但我实际上追求的是文本可以与图像混合在一起的东西，如下所示:

[![在此处输入图像描述][3]][3]

我有一种感觉，这可能与 DataType 代码有关，因为它允许所有图像或所有文本......所以这里也是我的结构的代码!

truct PostStruct {
        var dataType : Int = 0 // 0 for text, 1 for picture
        var date : NSDate
        var username : NSString 
        var text : NSString?
        var title : NSString?
        var image : PFFile?
        var uuid : NSString
        var profileImage : PFFile
        var caption : NSString?


        init (dataTypeInit: Int, dateInit : NSDate, usernameInit: String, textInit: String, titleInit: String, uuidInit: String,profileImageInit: PFFile) {
            dataType        = dataTypeInit
            date            = dateInit
            username        = usernameInit
            text            = textInit
            title           = titleInit
            uuid            = uuidInit
            profileImage    = profileImageInit
        }

        init (dataTypeInit: Int, dateInit : NSDate, usernameInit: String, imageInit: PFFile, uuidInit: String, profileImageInit: PFFile, captionInit: String) {
            dataType        = dataTypeInit
            date            = dateInit
            username        = usernameInit
            image           = imageInit
            uuid            = uuidInit
            profileImage    = profileImageInit
            caption         = captionInit
        }
    }


    var posts : [PostStruct] = []

更新

                for imageView in cell.threeImages {
                    imageView.image = UIImage(named: "ImagePlaceHolder")
                    for textView in cell.threeLabels {


                        let rowData = tableData[indexPath.row]

                for indexInRow in 0...2
                {
                    if indexInRow > rowData.posts.count
                    {
                        textView.hidden = true
                        imageView.hidden = true
                        // there are less posts for this row than the current index - so hide both the image and the text
                        // hide the imageView at position indexInRow
                        // hide the text view (label) at position indexInRow
                    }
                    else
                    {
                         let postt = rowData.posts[indexInRow]
                        // there is a post - check to see if it's text or an image
                        if postt.dataType == 1
                            // image type (replace this with an enumerator at some point)
                        {
                            postt.image!.getDataInBackgroundWithBlock { (data:NSData?, error:NSError?) -> Void in
                                if error == nil {
                                    if let imageData = data {
                                        imageView.image = UIImage(data: imageData)

                                        imageView.hidden = false
                                        textView.hidden = true

                                    }

                                }
                            }


                            // display the image in image at position indexInRow
                            // hide the text view (label) at position indexInRow
                        }
                        else
                        {
                            imageView.hidden = true
                            textView.hidden = false
                            textView.text = postt.text as? String
                            // hide the imageView at position indexInRow
                            // display the text view (label) at position indexInRow
                        }
                    }
                    }}
                }

预先感谢您的帮助!

Answer 1

我认为你必须继续除以三，这让事情变得过于复杂 - 为什么不为已经分成三行的表格 View 创建数据？

您可以拥有像这样的 rowData 结构

struct rowData
{
    var posts : [PostStruct] = []
}

并将其存储在像这样的类级变量中

var tableData : [rowData] = []

然后在加载数据时将其解析为该结构

// create an array of tableData, 
// where each element is of type rowData
// which has up to 3 `post` entries
// each of which is either an image or a text post
// the tableView methods are then based on tableData
var indexInRow = 0
for post in posts 
{
    if indexInRow == 0
    {
        // create a new rowData object
        tableData.append(rowData())
    }
    tableData[tableData.count - 1].posts.append(post)

    // using the modulo operator like this will return the remainder  of dividing by 3, so it will always be 0, 1, 2
    indexInRow = (indexInRow + 1) % 3
}

然后你的 tableView 方法看起来像这样

override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell
{
    let rowData = tableData[indexPath.row]

    for indexInRow in 0...2
    {
        if indexInRow > rowData.posts.count
        {
            // there are less posts for this row than the current index - so hide both the image and the text
            // hide the imageView at position indexInRow
            // hide the text view (label) at position indexInRow
        }
        else
        {
            // there is a post - check to see if it's text or an image

            // UPDATE
            let post = rowData.posts[indexInRow]
            // UPDATE

            if post.dataType == 0 // image type (replace this with an enumerator at some point)
            {
                // display the image in image at position indexInRow
                // hide the text view (label) at position indexInRow
            }
            else
            {
                // hide the imageView at position indexInRow
                // display the text view (label) at position indexInRow
            }
        }
    }
    return UITableViewCell()
}

override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int
{
    return tableData.count
}