如何在iphone应用程序中将饼图保存为pdf文件

Posted 2023-03-12

【中文标题】如何在iphone应用程序中将饼图保存为pdf文件

【英文标题】：how to save a pie graph in pdf file in iphone app

【发布时间】：2012-04-20 09:02:01

【问题描述】：

我有创建饼图的 iphone 应用程序，我希望该图表应保存在 iphone 的 pdf 文件中。

下面是 PieChart 的代码，但我如何将其保存为 pdf

   -(void)createGraph

  PieClass *myPieClass=[[PieClass alloc]initWithFrame:CGRectMake(400,40, 320, 230)];


  myPieClass.itemArray=[[NSArray alloc]initWithObjects:textFieldOne.text,textFieldTwo.text,textFieldThree.text, nil];

 myPieClass.myColorArray=[[NSArray alloc]initWithObjects:[UIColor purpleColor],[UIColor redColor],[UIColor orangeColor], nil];

 myPieClass.radius=100;
 [self.view addSubview:myPieClass];

  [self creatPDFFromView:@"mydata.pdf"];

 

    -(void)createPDFfromUIView:(UIView*)aView saveToDocumentsWithFileName:(NSString*)aFilename


     

// 创建一个可变数据对象用于更新二进制数据，如字节数组

  NSMutableData *pdfData = [NSMutableData data];

// 将pdf转换器指向可变数据对象和要转换的UIView

 UIGraphicsBeginPDFContextToData(pdfData, aView.bounds, nil);
 UIGraphicsBeginPDFPage();
 CGContextRef pdfContext = UIGraphicsGetCurrentContext();

// 将矩形绘制到视图中，因此这会被 UIGraphicsBeginPDFContextToData 捕获

   [aView.layer renderInContext:pdfContext];

// 移除 PDF 渲染上下文

    UIGraphicsEndPDFContext();

// 从 ios 设备检索文档目录

   NSArray* documentDirectories =   NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask,YES);

  NSString* documentDirectory = [documentDirectories objectAtIndex:0];
  NSString* documentDirectoryFilename = [documentDirectory stringByAppendingPathComponent:aFilename];

// 指示可变数据对象将其上下文写入磁盘上的文件

 [pdfData writeToFile:documentDirectoryFilename atomically:YES];
 NSLog(@"documentDirectoryFileName: %@",documentDirectoryFilename);
 

【问题讨论】：

也许这会有所帮助：[如何在 iOS 中将 UIView 转换为 PDF？][1] [1]：***.com/questions/5443166/…

【参考方案1】：

您要在该视图中创建为 pdf 的视图，请执行以下更改

NSString *fileName=@"PdfFromView.pdf";
[self createPDFfromUIView:self.view saveToDocumentsWithFileName:fileName];


-(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);

执行此代码后，转到文档文件夹，您将找到包含与您传入的视图相同内容的 pdf 文档

块引用

[self createPDFfromUIView:self.view saveToDocumentsWithFileName:fileName]

块引用

这个方法调用。 这段代码运行良好感谢 Antonio

【讨论】：

这段代码工作正常，但我没有在 pdf 文件中看到我的数据

代码正在运行，但我的 pdf 文件中没有看到任何数据

UITextView *textView=[[UITextView alloc]initWithFrame:CGRectMake(0, 0,320,250)]; textView.text=@"这是文本视图内容"; [self.view addSubview:textView]; NSString *fileName=@"PdfFromView.pdf"; [self createPDFfromUIView:self.view saveToDocumentsWithFileName:fileName]; 现在您发现 textview 内容在 pdf 文档中

【参考方案2】：

取自这里：

How to Convert UIView to PDF within iOS?

(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);

【讨论】：

以及如何给这个文件一个文件名

我可以称这个方法为 [self creatPDFFromView:fileName];

这只是一个例子，复制代码并用它做你想做的事，但是如果你想将它用作方法，是的，将它称为 ex: [self creatPDFFromView:@"myFile .pdf"];

如果你有空，我们可以聊聊这个解决方案吗

我已经尝试过了，但是在我的实现中作为您给定的代码出现异常