如何打印所有 WKWebView On AND Offscreen 内容 OSX 和 iOS

How does one Print all WKWebView On AND Offscreen content OSX and iOS

这个问题是关于打印 WKWebView 的所有内容(包括屏幕外内容)。 目前(仍然是 iOS 10.2 或 OSX 10.12 ) 没有工作解决方案和 none 的 Whosebug 工作假设解决方案。仅当您自己验证可以打印屏幕外内容时,才在此处提供答案,如果确实如此,则提供工作示例代码。

我正在尝试打印 ALL WKWebViewWebView OSX 10.10 或更高版本(目前 运行 10.11.2)。例如,宽 html table 中的列在视图之外并偏向右侧。 OSX 的早期版本会自动分页并正确打印所有 html.

我已经尝试使用 Whosebug 和其他地方提供的解决方案。所有人基本上都在说同样的事情,就是像这样打印 documentView

[[NSPrintOperation printOperationWithView:_webView.mainFrame.frameView.documentView printInfo:pInfo] runOperation];

这在 10.10 中对 WKWebViewWebView 停止工作。如果你这样做:

    [[NSPrintOperation printOperationWithView:_wkWebView printInfo:pInfo] runOperation];

您得到分页,但打印输出包含滚动条 WebView,而另一个 WKWebView 为您提供空白页。

我在 Apple 文档中找不到任何关于在 OSX 上打印 WKWebView 的内容。我也找不到任何特定于 OSX 而不是 iOS.

的答案

有人知道如何在 OSX 上打印这些吗?

更新:这是 WebView [Radar:23159060](仍然开放 2/2018) 和 WKWebView 甚至没有似乎解决了 OSX 上的打印问题。在网上查看此 class 的开源后,我看到 all 的 classes与打印有关的任何内容都在仅支持平台的条件编译块中:iOS.

更新第二部分:令人惊讶的是,这个荒谬的错误存在于这个 class 的所有实现中,包括 iOS 上的实现!我觉得这很荒谬 still 尽管文档声明使用这个(而且只有这个 class ) 在支持 iOS 8 或更高版本的应用程序中。现在不可能在 iOS 或 OSX 上打印 WebView 的所有屏幕上和 屏幕外 内容.失败的苹果。是时候解决这个问题了!我们都知道史蒂夫会怎么说....

更新第三部分 :)- 更令人惊讶的是,这个问题从 10.15.2 开始并没有得到解决,并且在 4 年多的时间里出现!!!这个问题一直存在(Apple waaaaaake up up up up up ....)。考虑到他们在 iOS 土地上使用 WKWebView 变得非常咄咄逼人,甚至拒绝不使用的应用程序(除非你试图支持 iOS 7),这真是令人惊讶。

更新第四部分(2020 年......你能相信吗?!?):在大苏尔,这仍然是一个问题。我通过编写解决方法解决了这个问题,请参阅下面接受的答案:

printOperationWithPrintInfo:

不打印屏幕外或在水平或垂直方向上滚出视图的所有内容。但是,它确实使用了您的 Print CSS ,这比:

略有优势
- (void)takeSnapshotWithConfiguration:(WKSnapshotConfiguration *)snapshotConfiguration 
                completionHandler:(void (^)(NSImage *snapshotImage, NSError *error))completionHandler;

为了让它工作,我做了:

NSPrintInfo *pInfo = [[NSPrintInfo alloc] initWithDictionary:printInfoDict];
pInfo.horizontalPagination = NSPrintingPaginationModeAutomatic;
pInfo.verticalPagination = NSPrintingPaginationModeAutomatic;
pInfo.verticallyCentered = YES;
pInfo.horizontallyCentered = YES;
pInfo.orientation = NSPaperOrientationLandscape;
pInfo.leftMargin = 30;
pInfo.rightMargin = 30;
pInfo.topMargin = 30;
pInfo.bottomMargin = 30;

NSPrintOperation *po = [_webView printOperationWithPrintInfo:pInfo];
po.showsPrintPanel = YES;
po.showsProgressPanel = YES;

// Without the next line you get an exception. Also it seems to
// completely ignore the values in the rect. I tried changing them
// in both x and y direction to include content scrolled off screen.
// It had no effect whatsoever in either direction. 
po.view.frame = _webView.bounds; 

// [printOperation runOperation] DOES NOT WORK WITH WKWEBVIEW, use 
[po runOperationModalForWindow:self.view.window delegate:self didRunSelector:@selector(printOperationDidRun:success:contextInfo:) contextInfo:nil];

**还有一些我不完全理解的事情。 wkWebView 的大小似乎无关紧要。如果我调整应用程序的大小以隐藏某些内容,它似乎仍然会在屏幕外抓取尽可能多的内容以适应指定的页面,但它似乎不知道如何对不适合页面大小的内容进行分页到其他页面。所以这似乎是问题所在。可能有一些方法可以解决这个问题,如果有人有线索 post 就在这里!!

在 iOS 中,我将 UIView.viewPrintFormatter() 传递给 UIActivityViewController 以允许用户打印所有内容

let myShare = [webView.viewPrintFormatter()]
let avc = UIActivityViewController(activityItems: myShare, applicationActivities: nil)

present(avc, animated: true, completion: nil)

我用尽了所有可能的方法来直接打印 WKWebView,但没有成功。我能想到的唯一解决方法是将网页转换为 PDF 对象,然后打印该对象。如果解决方法有效,我将更新代码。

这不是正确答案,因为 Apple 需要使用有效的打印方法或 .evaluateJavaScript("window.print()", completionHandler: nil)

提供正确答案

但我有一个愚蠢的解决方案 "works" 对我来说可能会帮助其他人解决这个问题。

第 1 步:抓住 HTML 并修复 <body> tag with <body onload='window.print()'>。如果您从某个地方获取 html 而不是加载您自己的,您将需要使用一些正则表达式。这个我就不说了。

第 2 步:将 html 保存在某个文件中,并将完整路径保存在变量中。在我的示例中:文件名

第 3 步:将您的打印按钮连接到此代码:

RunCommand(command: "/usr/bin/open \(filename)")

请参阅下面的 RunCommand 代码。这留下了一个愚蠢的 safari window,但它可以在不保存到文件的情况下打印一些东西,然后记住你把它贴在哪里,这样你就可以自己用 Safari 打开它来进行打印。

func RunCommand(command: String)  -> (success: Bool, result: String) {
        let cc = command.components(separatedBy: " ")
        let process = Process()
        process.launchPath = cc[0]
        var cp: [String] = []
        for i in (1..<cc.count) {
            cp.append(cc[i])
        }
        process.arguments = cp
        let pipe = Pipe()
        process.standardOutput = pipe
        process.launch()
        let data = pipe.fileHandleForReading.readDataToEndOfFile()
        if (data.count > 0) {
            let output = String(data: data, encoding: String.Encoding.utf8)
            // let output = NSString(data: data, encoding: String.Encoding.utf8.rawValue)
            return (success: true, result: output!)
        }
        return (success: true, result: "")

    }

如果 Apple 能够解决这个问题,那就太好了。我有一个内部应用程序,可以在 HTML 中完成所有报告,并且报告是您想要打印的内容。

我已经成功使用 SPI -[WKWebView _printOperationWithPrintInfo:] 通过了通常的 [NSPrintInfo sharedPrintInfo]。 请注意,您不能对返回的 NSPrintOperation 使用 -runOperation。您必须 使用 -runOperationModalForWindow:.... 这非常相似。问题出在 WebKit 内部,它需要一个 运行 runloop 和内部预览来了解页数。

它绝对适用于屏幕外内容,如果屏幕外的意思是“未完全显示在屏幕上”。我仍然有一个 WKWebView 显示在 window 中,但它非常小,只显示整个 webview 内容的一小部分(21 个 A4 页!)。希望这对您有所帮助!

PS:在 10.12、10.14 和 10.15 上测试。 代码是这样的:

     SEL printSelector = NSSelectorFromString(@"_printOperationWithPrintInfo:"); // This is SPI on WKWebView. Apparently existing since 10.11 ?
     
     NSMutableDictionary *printInfoDict = [[[NSPrintInfo sharedPrintInfo] dictionary] mutableCopy];
     printInfoDict[NSPrintJobDisposition] = NSPrintSaveJob; // means you want a PDF file, not printing to a real printer.
     printInfoDict[NSPrintJobSavingURL] = [NSURL fileURLWithPath:[@"~/Desktop/wkwebview_print_test.pdf" stringByExpandingTildeInPath]]; // path of the generated pdf file
     printInfoDict[NSPrintDetailedErrorReporting] = @YES; // not necessary         

     // customize the layout of the "printing"
     NSPrintInfo *customPrintInfo = [[NSPrintInfo alloc] initWithDictionary:printInfoDict]; 
     [customPrintInfo setHorizontalPagination: NSPrintingPaginationModeAutomatic];
     [customPrintInfo setVerticalPagination: NSPrintingPaginationModeAutomatic];
     [customPrintInfo setVerticallyCentered:NO];
     [customPrintInfo setHorizontallyCentered:NO];
     customPrintInfo.leftMargin = 0;
     customPrintInfo.rightMargin = 0;
     customPrintInfo.topMargin = 5;
     customPrintInfo.bottomMargin = 5;
  
     NSPrintOperation *printOperation = (NSPrintOperation*) [_webView performSelector:printSelector withObject:customPrintInfo];

     [printOperation setShowsPrintPanel:NO];
     [printOperation setShowsProgressPanel:NO];

//    BOOL printSuccess = [printOperation runOperation]; // THIS DOES NOT WORK WITH WKWEBVIEW! Use runOperationModalForWindow: instead (asynchronous)
     [printOperation runOperationModalForWindow:self.window delegate:self didRunSelector:@selector(printOperationDidRun:success:contextInfo:) contextInfo:nil]; // THIS WILL WORK, but is async

5 年后,我设法解决了 原来的问题,这是由于 MacOS 11 实施WKWebView printOperationWithPrintInfo 仍然无法正确处理滚出视图并向右滚动的内容。

根本问题似乎是剪辑区域边界之外的内容(尤其是右侧)没有得到正确处理。这可能是一个 WKWebView 错误,因为它似乎处理了垂直方向可见矩形下方的一些内容。

经过大量挖掘,发现其他人已经能够通过以下方式获取 NSView 的全部内容进行打印和正确分页:

  • 视图分离(不在屏幕上)。
  • 正在将框架设置为整个内容的大小。
  • 然后在分离视图上调用 printWithPrintInfo

我有一个解决方案的想法:

  1. 通过类别扩展 WKWebView,该类别具有将所有内容作为图像块获取的功能。它通过 JavaScript 在 MacOS 上执行此操作,在 iOS 上通过操作与 WKWebView 关联的 UIScrollView 来获取完整的内容大小,然后将内容的各个部分滚动到可见区域并将其快照为图像块网格。
  2. 创建 NSView or UIView 的子类,以正确的关系绘制所有图块。
  3. 在分离视图上调用 printWithPrintInfo

在 MacOS 10.14+ iOS 13+

上运行良好

在两个平台上,所有输出都正确分页(iOS 需要使用包含在相关 GitHub 项目中的 UIPrintPageRenderer),您可以在预览中使用打开为 PDF 并保存它作为文件等

我遇到的唯一缺点是未使用 Print CSS,考虑到 Apple 目前对 Print CSS 的支持很少,这并不重要。

所有工作代码都在 GitHub 此处:Full working source for iOS and MacOS

此源已过期 请参阅 Github

Header

//
//  WKWebView+UtilityFunctions.h
//  Created by Clifford Ribaudo on 12/24/20.
//
#import <WebKit/WebKit.h>

#ifdef _MAC_OS_  // Up to user to determine how they know this
    #define IMAGE_OBJ   NSImage
    #define VIEW_OBJ    NSView
#else
    #define IMAGE_OBJ   UIImage
    #define VIEW_OBJ    UIView
#endif

@interface TiledImageView : VIEW_OBJ
{
    NSArray *_imageTiles;
}
-(void)printWithPrintInfo:(NSPrintInfo *)pi;
-(instancetype)initWithFrame:(CGRect)frame imageTiles:(NSArray<NSArray *> *)imageTiles;
@end

@interface WKWebView (UtilityFunctions)
-(void)HTMLPageMetrics:(void (^)(CGSize htmlDocSize, CGSize visibleSize, NSError *error))completionHandler;
-(void)currentScrollXY:(void (^)(float x, float y, NSError *error))completionHandler;
-(void)scrollHTMLTo:(float)x topY:(float)y completionHandler:(void (^)(NSError *error))completionHandler;
-(void)imageTilesForHTMLPage:(CGSize)pageSize visbleRect:(CGSize)visibleRect imgData:(NSMutableArray<NSArray *> *)tileData completionHandler:(void (^)(NSError *error))completionHandler;
-(void)imageTile:(CGRect)imgRect fromPageOfSize:(CGSize)pageSize inViewOfSize:(CGSize)viewSize completionHandler:(void (^)(IMAGE_OBJ *tileImage, NSError *error))completionHandler;
@end

实施

//
//  WKWebView+UtilityFunctions.m
//  Created by Clifford Ribaudo on 12/24/20.
//
//  Works with MacOS v10.14+ and ??iOS 13+
//
#import "WKWebView+UtilityFunctions.h"

@implementation TiledImageView

-(instancetype)initWithFrame:(CGRect)frame imageTiles:(NSArray<NSArray *> *)imageTiles
{
    self = [super initWithFrame:NSRectFromCGRect(frame)];
    if(self) {
        _imageTiles = imageTiles;
    }
    return self;
}
-(BOOL)isFlipped {return YES;}

-(void)printWithPrintInfo:(NSPrintInfo *)pi
{
    NSPrintOperation *po = [NSPrintOperation printOperationWithView:self];
    po.printInfo = pi;
    [po runOperation];
}

- (void)drawRect:(NSRect)rect
{
    for(NSArray *imgData in _imageTiles)
    {
        NSRect drawRect = ((NSValue *)imgData[0]).rectValue;
        IMAGE_OBJ *img = imgData[1];
        [img drawInRect:drawRect];
    }
}
@end

@implementation WKWebView (UtilityFunctions)
//
//  Returns via Completion Handler:
//      htmlDocSize - The size of the entire <HTML> element, visible or not
//      visibleSize - The visible dimensions of the page, essentially WKWebView bounds minus HTML scroll bar dimensions
//
-(void)HTMLPageMetrics:(void (^)(CGSize htmlDocSize, CGSize visibleSize, NSError *error))completionHandler
{
    //
    //  Anonymous Function - gets Size of entire HTML element and visible size.
    //  Result String = Full X, Full Y, Visible X, Visible Y
    //
    NSString *jsGetPageMetrics = @"(function(){return document.documentElement.scrollWidth + ',' + document.documentElement.scrollHeight + ',' + document.documentElement.clientWidth + ',' +document.documentElement.clientHeight;})();";

    // Execute JS in WKWebView
    [self evaluateJavaScript:jsGetPageMetrics completionHandler:^(id result, NSError *error)
    {
        CGSize htmlSize = CGSizeMake(0, 0);
        CGSize visibleSize = CGSizeMake(0, 0);
    
        if(!error && result)
        {
            NSArray<NSString *> *data = [[NSString stringWithFormat:@"%@", result] componentsSeparatedByString:@","];
            htmlSize = CGSizeMake([data[0] floatValue], [data[1] floatValue]);
            visibleSize = CGSizeMake([data[2] floatValue], [data[3] floatValue]);
        }
        else
            NSLog(@"JS error getting page metrics: %@", error.description);
    
        completionHandler(htmlSize, visibleSize, error);
    }];
}

//
//  Get <HTML> element current scroll position (x,y) and return to completeion handler:
//      x = document.documentElement.scrollLeft
//      y = document.documentElement.scrollTop
//
-(void)currentScrollXY:(void (^)(float X, float Y, NSError *error))completionHandler
{
    NSString *jsGetPageMetrics = @"(function(){return document.documentElement.scrollLeft + ',' + document.documentElement.scrollTop;})();";

    // Execute JS in WKWebView
    [self evaluateJavaScript:jsGetPageMetrics completionHandler:^(id result, NSError *error) {
        if(!error && result)
        {
            NSArray<NSString *> *data = [[NSString stringWithFormat:@"%@", result] componentsSeparatedByString:@","];
            completionHandler([data[0] floatValue], [data[1] floatValue], error);
        }
        else {
            NSLog(@"JS error getting page metrics: %@", error.localizedDescription);
            completionHandler(0, 0, error);
        }
    }];
}

//
//  Scroll the current HTML page to x, y using scrollTo(x,y) on the <HTML> element
//  Optional Completion Handler to do something when scroll finished
//
-(void)scrollHTMLTo:(float)x topY:(float)y completionHandler:(void (^)(NSError *error))completionHandler
{
    NSString *js = [NSString stringWithFormat:@"document.documentElement.scrollTo(%0.f, %0.f);", x, y];

    // Execute JS in WKWebView
    [self evaluateJavaScript:js completionHandler:^(id result, NSError *error)
    {
        dispatch_time_t delay = dispatch_time(DISPATCH_TIME_NOW, .25 * NSEC_PER_SEC);
        dispatch_after(delay, dispatch_get_main_queue(), ^{
            if(completionHandler) completionHandler(error);
        });
        if(error) NSLog(@"JS error scrollTo %@", error.localizedDescription);
    }];
}

//
//  Called Recursively until tiles are obtained for the entire pageRect.
//  Tiles are the size of visibleRect (WKWebView.bounts) but can be smaller.
//  tileData - Array of arrays holding CGRect & Img.
//
-(void)imageTilesForHTMLPage:(CGSize)pageSize visbleRect:(CGSize)visibleSize imgData:(NSMutableArray<NSArray *> *)tileData completionHandler:(void (^)(NSError *error))completionHandler
{
    __block CGRect currentRect;                         // In coordinates of pageSize (full).

    if(tileData.count == 0) {                           // No image tiles yet. Start at top left of html page for visible WKWebView bounds
        currentRect.origin.x = currentRect.origin.y = 0.0;
        currentRect.size = visibleSize;
    }
    else {
        NSArray *lastTile = [tileData lastObject];      // Calculate what the next tile rect is or call handler if done.
        CGRect lastTileRect;
    
#ifdef _MAC_OS_
        lastTileRect = ((NSValue *)lastTile[0]).rectValue;
#else
    lastTileRect = ((NSValue *)lastTile[0]).CGRectValue;
#endif
        // Check if anything more to get to right of last tile
        if((lastTileRect.origin.x + lastTileRect.size.width) < pageSize.width)
        {
            currentRect.origin.x = lastTileRect.origin.x + lastTileRect.size.width + 1;     // Next x to right of last tile
            currentRect.origin.y = lastTileRect.origin.y;                                   // Works on all rows
            currentRect.size.height = lastTileRect.size.height;
        
            currentRect.size.width = pageSize.width - currentRect.origin.x;                 // Get width of next tile to right of last
            if(currentRect.size.width > visibleSize.width)                                  // If more tiles to right use visible width
                currentRect.size.width = visibleSize.width;
        }
        else if((lastTileRect.origin.y + lastTileRect.size.height) < pageSize.height)       // New Row
        {
            currentRect.origin.x = 0;          // Reset x back to left side of hmtl
            currentRect.size.width = visibleSize.width;                                     // Reset width back to view width
        
            currentRect.origin.y = lastTileRect.origin.y + lastTileRect.size.height + 1;    // Get y below last row
            currentRect.size.height = pageSize.height - currentRect.origin.y;
            if(currentRect.size.height > visibleSize.height)                                // If more rows below use row height
                currentRect.size.height = visibleSize.height;
        }
        else {
            completionHandler(nil);
            return;
        }
    }
    [self imageTile:currentRect fromPageOfSize:pageSize inViewOfSize:visibleSize completionHandler:^(NSImage *tileImage, NSError *error)
    {
        if(error || !tileImage) {
            NSLog(@"Error getting image tiles %@", error.description);
            completionHandler(error);
            return;
        }
#ifdef _MAC_OS_
        [tileData addObject:@[[NSValue valueWithRect:NSRectFromCGRect(currentRect)], tileImage]];
#else
        [tileData addObject:@[[NSValue valueWithCGRect:currentRect], tileImage]];
#endif
        [self imageTilesForHTMLPage:(CGSize)pageSize visbleRect:(CGSize)visibleSize imgData:(NSMutableArray<NSArray *> *)tileData completionHandler:completionHandler];
    }];
}

//
//  ImgRect = location of rect in full page size. Has to be translated into what is visible and where.
//  pageSize = Full size of HTML page, visible or not.
//  viewSize = essentially the wkwebview.bounds.size - HTML scroll bars.
//
-(void)imageTile:(CGRect)imgRect fromPageOfSize:(CGSize)pageSize inViewOfSize:(CGSize)viewSize completionHandler:(void (^)(IMAGE_OBJ *tileImage, NSError *error))completionHandler
{
    float x = imgRect.origin.x;     // Always do this to make the desired rect visible in the rect of viewSize
    float y = imgRect.origin.y;

    CGRect rectToGetFromView;

    rectToGetFromView.origin.x = 0;
    rectToGetFromView.origin.y = 0;
    rectToGetFromView.size = imgRect.size;

    // If img is smaller than the viewport, determine where it is after scroll
    if(imgRect.size.width < viewSize.width)
        rectToGetFromView.origin.x = viewSize.width - imgRect.size.width;

    if(imgRect.size.height < viewSize.height)
        rectToGetFromView.origin.y = viewSize.height - imgRect.size.height;

    [self scrollHTMLTo:x topY:y completionHandler:^(NSError *error)
    {
        if(!error) {
            WKSnapshotConfiguration *sc = [WKSnapshotConfiguration new];
            sc.rect = rectToGetFromView;
            [self takeSnapshotWithConfiguration:sc completionHandler:^(IMAGE_OBJ *img, NSError *error)
            {
                if(error) NSLog(@"Error snapshotting image tile: %@", error.description);
                completionHandler(img, error);
            }];
        }
        else {
            NSLog(@"Error scrolling for next image tile %@", error.description);
            completionHandler(nil, error);
        }
    }];
}
@end

用法

在为您的 WKWebView 处理打印的任何内容中使用类别,如下所示:

-(void)print:(id)sender
{
    // Set this as per your needs
    NSPrintInfo *pInfo = [NSPrintInfo sharedPrintInfo];
    pInfo.verticallyCentered = YES;
    pInfo.horizontallyCentered = NO;
    pInfo.horizontalPagination = NSAutoPagination;
    pInfo.verticalPagination = NSAutoPagination;
    pInfo.orientation = NSPaperOrientationLandscape;
    pInfo.bottomMargin = 30;
    pInfo.topMargin = 30;
    pInfo.leftMargin = 30;
    pInfo.rightMargin = 30;
    pInfo.scalingFactor = .60;
    
    [_webView HTMLPageMetrics:^(CGSize htmlSize, CGSize visibleSize, NSError *error)
    {
        self->_imgTileData = [NSMutableArray new];
 
        [self->_webView imageTilesForHTMLPage:htmlSize visbleRect:visibleSize imgData:self->_imgTileData completionHandler:^(NSError *error) {
            if(!error) {
                TiledImageView *tiv = [[TiledImageView alloc] initWithFrame:CGRectMake(0,0,htmlSize.width,htmlSize.height) imageTiles:self->_imgTileData];
                [tiv printWithPrintInfo:pInfo];
            }
        }];
    }
}

这是作为 Github 要点的代码:Above code

然后从下面的内容 WKWebView 开始向右滚动:

一个人得到这个带有正确分页的打印对话框:

这是我的 swift 版本(针对 OSX 11 更新)@Altimac 的解决方案。

@available(OSX 11.0, *)
extension BrowserViewController
{
    func print(pdf: Bool)
    {
        guard var printInfoDictionary = NSPrintInfo.shared.dictionary().mutableCopy() as? [NSPrintInfo.AttributeKey: Any] else { return }
        
        printInfoDictionary[NSPrintInfo.AttributeKey.jobDisposition] = pdf ? NSPrintInfo.JobDisposition.preview : NSPrintInfo.JobDisposition.spool
        printInfoDictionary[NSPrintInfo.AttributeKey.detailedErrorReporting] = true
        
        let printInfo = NSPrintInfo(dictionary: printInfoDictionary)
        printInfo.horizontalPagination = .automatic
        printInfo.verticalPagination = .automatic
        printInfo.isVerticallyCentered = false
        printInfo.isHorizontallyCentered = false
        printInfo.leftMargin = 10
        printInfo.rightMargin = 10
        printInfo.topMargin = 10
        printInfo.bottomMargin = 10
        
        let printOperation = theWebView.printOperation(with: printInfo)
        
        printOperation.showsPrintPanel = false
        printOperation.showsProgressPanel = false
        
        printOperation.runModal(for: self.view.window!, delegate: self, didRun: nil, contextInfo: nil)
    }
}

似乎至少对我有用。