打印 UIView，但不是通过渲染为位图图像 [英] Print a UIView, but NOT by rendering as a bitmap image

问题描述

假设您有一个只有文本(即 UILabel)和一些黑线的简单 UIView.

Say you have a simple UIView with only text (ie, UILabel) and maybe some black lines.

这正是打印 UIView 的方法...

Here's exactly how you can print that UIView...

将其渲染为 UIImage，然后打印...

render it as a UIImage, and print that...

- (IBAction)printB:(id)sender
    {
    // we want to print a normal view ... some UILabels, maybe a black line

    // in this technique, depressingly we CREATE AN IMAGE of the view...

    // step 1. make a UIImage, of the whole view.

    UIGraphicsBeginImageContextWithOptions(self.printMe.bounds.size, NO, 0.0);

    // [self.printMe.layer renderInContext:UIGraphicsGetCurrentContext()];
    // UIImage *asAnImage = UIGraphicsGetImageFromCurrentImageContext();
    // .... or, more futuristically.....
    [self.printMe drawViewHierarchyInRect:self.printMe.bounds
        afterScreenUpdates:NO];
    UIImage *snapshotImage = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    // step 2. choose grayscale, etc

    UIPrintInfo *info = [UIPrintInfo printInfo];
    info.orientation = UIPrintInfoOrientationPortrait;
    info.outputType = UIPrintInfoOutputGrayscale;

    // step 3, print that UIImage

    UIPrintInteractionController *pic =
       [UIPrintInteractionController sharedPrintController];
    pic.delegate = self;
    //pic.printingItem = asAnImage;
    pic.printingItem = snapshotImage;
    pic.printInfo = info;

    UIPrintInteractionCompletionHandler completionHandler =
    ^(UIPrintInteractionController *pic, BOOL completed, NSError *error)
        {
        if (error)
            NSLog(@"failed... %@ %ld", error.domain, (long)error.code);
        if (completed)
            NSLog(@"completed yes");
        else
            NSLog(@"completed no");
        };     

    [pic presentAnimated:YES completionHandler:completionHandler];
    }

但这会给你带来糟糕的结果.这是一种可笑的印刷排版方式.它应该作为附言或其他东西发送.

But this gives you crap results. It's a ridiculous way to print typography. It should be being sent as postscript, or something.

在 iPad 屏幕上...

on iPad screen...

打印时..

请注意，当然，如果您使用视网膜 ipad 会好一点，但这不是重点.将文本信息、黑线打印为图像是荒谬的.

Note that, of course, if you use a retina ipad it's a bit better, but that's not the point. it's ridiculous to print text information, black lines, as an image.

现在，你认为你可以打印一个像这样的 UIView ......

Now, you'd think you could print a UIView something like this ...

pic.printFormatter = [someUIView viewPrintFormatter];

但无论如何我都无法让它发挥作用.

but I can't get that to work no matter what I try.

有人有这方面的东西吗?谢谢！

Does anyone have anything on this? Thanks!

PS - 请注意，在 iOS 中，我们最近从使用 renderInContext 更改为使用快照调用.这对这里的问题完全没有影响，干杯.

PS - note that in iOS, we've recently changed from using renderInContext to using the snapshot call. It makes absolutely no difference to the issue here, cheers.

推荐答案

As Apple Doc 状态，UIView 的 viewPrintFormatter 属性定义在 UIView 类别中，但它仅适用于以下类型的实例:UITextView、MKMapView 和 >UIWebView.

As Apple Doc states, viewPrintFormatter attribute of UIView is defined in a UIView category but it's available only for instances of type: UITextView, MKMapView and UIWebView.

所以你可以:

• 使用图层属性打印 UIView 并展平其所有内容
• 使用要打印的内容初始化 UIWebView 并赋予其 viewPrintFormatter 属性到 pageRenderer 并渲染每个页面

这篇关于打印 UIView，但不是通过渲染为位图图像的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！