iOS开发 - tableView长截图iOS15适配(Swift版)

2021年苹果秋季发布会之后，iOS15的推出，给开发带来了不少的适配问题。（可恶！）

没办法，那是爸爸。我改咯～

先贴上在iOS14及以下版本，正常的长截图完整代码.

1. 建立一个UITableView的扩展extension

extension UITableView {
    
    /// 获取最大高度
    /// - Parameters:
    ///   - maxRowCount: 最大row的count
    ///   - maxSectionCount: 最大section的count，为0表示所有
    public func getMaxHeight(with maxRowCount: Int, maxSectionCount: Int = 0) -> CGFloat {
        var sectionCount = maxSectionCount
        if maxSectionCount >= numberOfSections || maxSectionCount <= 0 {
            sectionCount = numberOfSections
        }
        var maxHeight: CGFloat = tableHeaderView?.frame.size.height ?? 0;
        for sectionIndex in 0.. maxRowCount) {
                rowCount = maxRowCount;
            }
            
            maxHeight += delegate?.tableView?(self, heightForHeaderInSection: sectionCount) ?? 0
            for rowIndex in 0.. UIImage? {
        var viewImage: UIImage?
        
        let savedContentOffset = contentOffset
        let savedFrame = frame
        
        let imageHeight = maxHeight > 0 ? maxHeight :contentSize.height
        var screensInTable = 0
        
        if (frame.size.height != 0) {
            screensInTable = Int(ceil(imageHeight / frame.size.height))
        }
        
        let sectionNum = numberOfSections
        
//        autoreleasepool {
            let imageSize = CGSize(width: frame.size.width, height: maxHeight)
            UIGraphicsBeginImageContextWithOptions(imageSize, false, UIScreen.main.scale)
            
            frame = CGRect(x: 0, y: 0, width: contentSize.width, height: imageHeight)
            
            for i in 0..

2. 使用代码. 这里的10，是指最大row的数量。详细代码在extension，就不叙述了。

guard let image = longShareImageTableView.generateTableViewImage(with: longShareImageTableView.getMaxHeight(with: 10)) else {

                return
            }

            shareImage = image

到了iOS15，截图就会缺失了一部分，举个栗子

[email protected]

很是迷茫，网上好像暂时没有相应的资料和解决办法。后来在https://jishuin.proginn.com/p/763bfbd564b3这篇文章中，找到了灵感之处。

if #available(iOS 13, *) {
       //iOS 13 系统截屏需要改变tableview 的bounds
       scrollView.layer.bounds = CGRect(x: oldBounds.origin.x, y: oldBounds.origin.y, width: contentSize.width, height: contentSize.height)
   }
   //偏移量归零
   scrollView.contentOffset = CGPoint.zero
   //frame变为contentSize
   scrollView.frame = CGRect(x: 0, y: 0, width: scrollView.contentSize.width, height: scrollView.contentSize.height)

但实测之后发现，把这段结合到自己的截图方法中后，反而会令iOS13版本的截图缺失，iOS15倒是正常了。。。

最后只能把代码变成iOS15之后使用了，最终的代码如下

/// 获取指定高度的tableView image
    /// - Parameter maxHeight: 最大高度
    public func generateTableViewImage(with maxHeight: CGFloat) -> UIImage? {
        var viewImage: UIImage?
        
        let savedContentOffset = contentOffset
        let savedFrame = frame
        
        let imageHeight = maxHeight > 0 ? maxHeight :contentSize.height
        var screensInTable = 0
        
        if (frame.size.height != 0) {
            screensInTable = Int(ceil(imageHeight / frame.size.height))
        }
        
        let sectionNum = numberOfSections
        
//        autoreleasepool {
            let imageSize = CGSize(width: frame.size.width, height: maxHeight)
            UIGraphicsBeginImageContextWithOptions(imageSize, false, UIScreen.main.scale)
            
            frame = CGRect(x: 0, y: 0, width: contentSize.width, height: imageHeight)
            
            let oldBounds = layer.bounds
            
        
            if #available(iOS 15, *) {
                //iOS 15 系统截屏需要改变tableview 的bounds
                layer.bounds = CGRect(x: oldBounds.origin.x,
                                                 y: oldBounds.origin.y,
                                                 width: contentSize.width,
                                                 height: contentSize.height)
                
                //偏移量归零
                contentOffset = CGPoint.zero
                //frame变为contentSize
                frame = CGRect(x: 0, y: 0, width: contentSize.width, height: contentSize.height)
            }
            
            
            for i in 0..

[email protected]

打完！收工！
攰死个人了