关于如何在App的UIView中显示PDF有很多资源。我现在正在做的是从UIViews创建一个PDF。
例如，我有一个UIView，其子视图如Textviews，UILabels，UIImages，那么如何将一个大的UIView整体转换为包括所有子视图和子子视图到PDF？
我检查了Apple's iOS reference。但是，它只涉及将文本/图像片段写入PDF文件。
我面临的问题是我想以PDF格式写入文件的内容很多。如果我将它们逐个写入PDF，那将是一项巨大的工作。这就是为什么我正在寻找一种方法将UIViews写入PDF甚至位图。
我已经尝试过在Stack Overflow中从其他Q / A复制的源代码。但它只给了我一张带有UIView边界大小的空白PDF。
-(void)createPDFfromUIView:(UIView*)aView saveToDocumentsWithFileName:(NSString*)aFilename
{
// Creates a mutable data object for updating with binary data, like a byte array
NSMutableData *pdfData = [NSMutableData data];
// Points the pdf converter to the mutable data object and to the UIView to be converted
UIGraphicsBeginPDFContextToData(pdfData, aView.bounds, nil);
UIGraphicsBeginPDFPage();
// draws rect to the view and thus this is captured by UIGraphicsBeginPDFContextToData
[aView drawRect:aView.bounds];
// remove PDF rendering context
UIGraphicsEndPDFContext();
// Retrieves the document directories from the iOS device
NSArray* documentDirectories = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask,YES);
NSString* documentDirectory = [documentDirectories objectAtIndex:0];
NSString* documentDirectoryFilename = [documentDirectory stringByAppendingPathComponent:aFilename];
// instructs the mutable data object to write its context to a file on disk
[pdfData writeToFile:documentDirectoryFilename atomically:YES];
NSLog(@"documentDirectoryFileName: %@",documentDirectoryFilename);
}
请帮忙。谢谢。
请注意，以下方法仅创建视图的位图;它不会创建实际的排版。
(void)createPDFfromUIView:(UIView*)aView saveToDocumentsWithFileName:(NSString*)aFilename
{
// Creates a mutable data object for updating with binary data, like a byte array
NSMutableData *pdfData = [NSMutableData data];
// Points the pdf converter to the mutable data object and to the UIView to be converted
UIGraphicsBeginPDFContextToData(pdfData, aView.bounds, nil);
UIGraphicsBeginPDFPage();
CGContextRef pdfContext = UIGraphicsGetCurrentContext();
// draws rect to the view and thus this is captured by UIGraphicsBeginPDFContextToData
[aView.layer renderInContext:pdfContext];
// remove PDF rendering context
UIGraphicsEndPDFContext();
// Retrieves the document directories from the iOS device
NSArray* documentDirectories = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask,YES);
NSString* documentDirectory = [documentDirectories objectAtIndex:0];
NSString* documentDirectoryFilename = [documentDirectory stringByAppendingPathComponent:aFilename];
// instructs the mutable data object to write its context to a file on disk
[pdfData writeToFile:documentDirectoryFilename atomically:YES];
NSLog(@"documentDirectoryFileName: %@",documentDirectoryFilename);
}
还要确保导入：QuartzCore / QuartzCore.h
另外，如果有人有兴趣，这里是Swift 3代码：
func createPdfFromView(aView: UIView, saveToDocumentsWithFileName fileName: String)
{
let pdfData = NSMutableData()
UIGraphicsBeginPDFContextToData(pdfData, aView.bounds, nil)
UIGraphicsBeginPDFPage()
guard let pdfContext = UIGraphicsGetCurrentContext() else { return }
aView.layer.render(in: pdfContext)
UIGraphicsEndPDFContext()
if let documentDirectories = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true).first {
let documentsFileName = documentDirectories + "/" + fileName
debugPrint(documentsFileName)
pdfData.write(toFile: documentsFileName, atomically: true)
}
}
如果有人有兴趣，这里是Swift 2.1代码：
func createPdfFromView(aView: UIView, saveToDocumentsWithFileName fileName: String)
{
let pdfData = NSMutableData()
UIGraphicsBeginPDFContextToData(pdfData, aView.bounds, nil)
UIGraphicsBeginPDFPage()
guard let pdfContext = UIGraphicsGetCurrentContext() else { return }
aView.layer.renderInContext(pdfContext)
UIGraphicsEndPDFContext()
if let documentDirectories = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true).first {
let documentsFileName = documentDirectories + "/" + fileName
debugPrint(documentsFileName)
pdfData.writeToFile(documentsFileName, atomically: true)
}
}
从UIView创建PDF的一种超级简单方法是使用UIView扩展
Swift 4.2
extension UIView {
// Export pdf from Save pdf in drectory and return pdf file path
func exportAsPdfFromView() -> String {
let pdfPageFrame = self.bounds
let pdfData = NSMutableData()
UIGraphicsBeginPDFContextToData(pdfData, pdfPageFrame, nil)
UIGraphicsBeginPDFPageWithInfo(pdfPageFrame, nil)
guard let pdfContext = UIGraphicsGetCurrentContext() else { return "" }
self.layer.render(in: pdfContext)
UIGraphicsEndPDFContext()
return self.saveViewPdf(data: pdfData)
}
// Save pdf file in document directory
func saveViewPdf(data: NSMutableData) -> String {
let paths = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
let docDirectoryPath = paths[0]
let pdfPath = docDirectoryPath.appendingPathComponent("viewPdf.pdf")
if data.write(to: pdfPath, atomically: true) {
return pdfPath.path
} else {
return ""
}
}
}
图片来源：http://www.swiftdevcenter.com/create-pdf-from-uiview-wkwebview-and-uitableview/
这将从UIView生成PDF并打开打印对话框，目标C.将- (IBAction)PrintPDF:(id)sender附加到屏幕上的按钮。添加#import <QuartzCore/QuartzCore.h>框架
H档案
@interface YourViewController : UIViewController <MFMailComposeViewControllerDelegate,UIPrintInteractionControllerDelegate>
{
UIPrintInteractionController *printController;
}
- (IBAction)PrintPDF:(id)sender;
M文件
-(void)createPDFfromUIView:(UIView*)aView saveToDocumentsWithFileName:(NSString*)aFilename
{
NSMutableData *pdfData = [NSMutableData data];
UIGraphicsBeginPDFContextToData(pdfData, aView.bounds, nil);
UIGraphicsBeginPDFPage();
CGContextRef pdfContext = UIGraphicsGetCurrentContext();
[aView.layer renderInContext:pdfContext];
UIGraphicsEndPDFContext();
NSArray* documentDirectories = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask,YES);
NSString* documentDirectory = [documentDirectories objectAtIndex:0];
NSString* documentDirectoryFilename = [documentDirectory stringByAppendingPathComponent:aFilename];
NSString *file = [documentDirectory stringByAppendingPathComponent:@"yourPDF.pdf"];
NSURL *urlPdf = [NSURL fileURLWithPath: file];
[pdfData writeToFile:documentDirectoryFilename atomically:YES];
NSLog(@"documentDirectoryFileName: %@",documentDirectoryFilename);
}
- (IBAction)PrintPDF:(id)sender
{
[self createPDFfromUIView:self.view saveToDocumentsWithFileName:@"yourPDF.pdf"];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *path = [documentsDirectory stringByAppendingPathComponent:@"yourPDF.pdf"];
NSData *myData = [NSData dataWithContentsOfFile: path];
UIPrintInteractionController *pic = [UIPrintInteractionController sharedPrintController];
if(pic && [UIPrintInteractionController canPrintData: myData] ) {
pic.delegate = self;
UIPrintInfo *printInfo = [UIPrintInfo printInfo];
printInfo.outputType = UIPrintInfoOutputGeneral;
printInfo.jobName = [path lastPathComponent];
printInfo.duplex = UIPrintInfoDuplexLongEdge;
pic.printInfo = printInfo;
pic.showsPageRange = YES;
pic.printingItem = myData;
void (^completionHandler)(UIPrintInteractionController *, BOOL, NSError *) = ^(UIPrintInteractionController *pic, BOOL completed, NSError *error) {
//self.content = nil;
if(!completed && error){
NSLog(@"Print Error: %@", error);
}
};
[pic presentAnimated:YES completionHandler:completionHandler];
}
}
使用Swift 5 / iOS 12，您可以将CALayer的render(in:)方法与UIGraphicsPDFRenderer的writePDF(to:withActions:)方法结合使用，以便从UIView实例创建PDF文件。
以下Playground示例代码显示了如何使用render(in:)和writePDF(to:withActions:)：
import UIKit
import PlaygroundSupport
let view = UIView(frame: CGRect(x: 0, y: 0, width: 100, height: 100))
view.backgroundColor = .orange
let subView = UIView(frame: CGRect(x: 20, y: 20, width: 40, height: 60))
subView.backgroundColor = .magenta
view.addSubview(subView)
let outputFileURL = PlaygroundSupport.playgroundSharedDataDirectory.appendingPathComponent("MyPDF.pdf")
let pdfRenderer = UIGraphicsPDFRenderer(bounds: view.bounds)
do {
try pdfRenderer.writePDF(to: outputFileURL, withActions: { context in
context.beginPage()
view.layer.render(in: context.cgContext)
})
} catch {
print("Could not create PDF file: \(error)")
}
注意：要在Playground中使用playgroundSharedDataDirectory，首先需要在macOS“Documents”文件夹中创建一个名为“Shared Playground Data”的文件夹。
下面的UIViewController子类完整实现显示了重构iOS应用程序的前一个示例的可能方法：
import UIKit
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
let view = UIView(frame: CGRect(x: 0, y: 0, width: 100, height: 100))
view.backgroundColor = .orange
let subView = UIView(frame: CGRect(x: 20, y: 20, width: 40, height: 60))
subView.backgroundColor = .magenta
view.addSubview(subView)
createPDF(from: view)
}
func createPDF(from view: UIView) {
let documentDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!
let outputFileURL = documentDirectory.appendingPathComponent("MyPDF.pdf")
print("URL:", outputFileURL) // When running on simulator, use the given path to retrieve the PDF file
let pdfRenderer = UIGraphicsPDFRenderer(bounds: view.bounds)
do {
try pdfRenderer.writePDF(to: outputFileURL, withActions: { context in
context.beginPage()
view.layer.render(in: context.cgContext)
})
} catch {
print("Could not create PDF file: \(error)")
}
}
}
我不知道为什么，但是casilic的答案给了我iOS6.1上的空白屏幕。以下代码有效。
-(NSMutableData *)createPDFDatafromUIView:(UIView*)aView
{
// Creates a mutable data object for updating with binary data, like a byte array
NSMutableData *pdfData = [NSMutableData data];
// Points the pdf converter to the mutable data object and to the UIView to be converted
UIGraphicsBeginPDFContextToData(pdfData, aView.bounds, nil);
UIGraphicsBeginPDFPage();
CGContextRef pdfContext = UIGraphicsGetCurrentContext();
// draws rect to the view and thus this is captured by UIGraphicsBeginPDFContextToData
[aView.layer renderInContext:pdfContext];
// remove PDF rendering context
UIGraphicsEndPDFContext();
return pdfData;
}
-(NSString*)createPDFfromUIView:(UIView*)aView saveToDocumentsWithFileName:(NSString*)aFilename
{
// Creates a mutable data object for updating with binary data, like a byte array
NSMutableData *pdfData = [self createPDFDatafromUIView:aView];
// Retrieves the document directories from the iOS device
NSArray* documentDirectories = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask,YES);
NSString* documentDirectory = [documentDirectories objectAtIndex:0];
NSString* documentDirectoryFilename = [documentDirectory stringByAppendingPathComponent:aFilename];
// instructs the mutable data object to write its context to a file on disk
[pdfData writeToFile:documentDirectoryFilename atomically:YES];
NSLog(@"documentDirectoryFileName: %@",documentDirectoryFilename);
return documentDirectoryFilename;
}