在PDF文件中的内容之后绘制图像

时间:2013-01-21 10:31:08

标签: ios objective-c pdf

我最近一直在寻找一个很好的PDF教程,文档等等。

我最终使用了this代码,但问题很少。

方案

我有一个包含标签,textView和imageView的视图。 现在,我们将调用标签name,textView description和imageView image

该名称作为标题。

描述非常非常可变,它可以是从2行到某些页面。

图片应该放在说明文字的末尾。

我正在使用此代码:

- (void)generatePDF{
    NSString *fileName = [NSString stringWithFormat:@"%@.pdf",nameString];
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    NSString *pdfFileName = [documentsDirectory stringByAppendingPathComponent:fileName];

    CFAttributedStringRef currentText = CFAttributedStringCreate(NULL,
                                                                 (CFStringRef)descriptionString, NULL);
    if (currentText) {
        CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString(currentText);
        if (framesetter) {

            // Create the PDF context using the default page: currently constants at the size
            // of 612 x 792.
            UIGraphicsBeginPDFContextToFile(pdfFileName, CGRectZero, nil);

            CFRange currentRange = CFRangeMake(0, 0);
            NSInteger currentPage = 0;
            BOOL done = NO;

            do {
                // Mark the beginning of a new page.
                UIGraphicsBeginPDFPageWithInfo(CGRectMake(0, 0, kDefaultPageWidth,
                                                          kDefaultPageHeight), nil);
                [self drawHeader]
                // Draw a page number at the bottom of each page
                currentPage++;
                [self drawPageNumber:currentPage];

                // Render the current page and update the current range to
                // point to the beginning of the next page.
                currentRange = [self renderPage:currentPage withTextRange:
                                currentRange andFramesetter:framesetter];

                // If we're at the end of the text, exit the loop.
                if (currentRange.location == CFAttributedStringGetLength
                    ((CFAttributedStringRef)currentText))
                    done = YES;
            } while (!done);

            // Close the PDF context and write the contents out.
            UIGraphicsEndPDFContext();

            // Release the framewetter.
            CFRelease(framesetter);

        } else {
            NSLog(@"Could not create the framesetter needed to lay out the atrributed string.");
        }
        // Release the attributed string.
        CFRelease(currentText);
    } else {
        NSLog(@"Could not create the attributed string for the framesetter");
    }

}

- (CFRange)renderPage:(NSInteger)pageNum withTextRange:(CFRange)currentRange
       andFramesetter:(CTFramesetterRef)framesetter
{
    // Get the graphics context.
    CGContextRef    currentContext = UIGraphicsGetCurrentContext();

    // Put the text matrix into a known state. This ensures
    // that no old scaling factors are left in place.
    CGContextSetTextMatrix(currentContext, CGAffineTransformIdentity);

    // Create a path object to enclose the text. Use 72 point
    // margins all around the text.
    CGRect    frameRect = CGRectMake(22,72, 468, 648);
    CGMutablePathRef framePath = CGPathCreateMutable();
    CGPathAddRect(framePath, NULL, frameRect);

    // Get the frame that will do the rendering.
    // The currentRange variable specifies only the starting point. The framesetter
    // lays out as much text as will fit into the frame.
    CTFrameRef frameRef = CTFramesetterCreateFrame(framesetter, currentRange, framePath, NULL);
    CGPathRelease(framePath);

    // Core Text draws from the bottom-left corner up, so flip
    // the current transform prior to drawing.
    CGContextTranslateCTM(currentContext, 0, kDefaultPageHeight);
    CGContextScaleCTM(currentContext, 1.0, -1.0);

    // Draw the frame.
    CTFrameDraw(frameRef, currentContext);

    // Update the current range based on what was drawn.
    currentRange = CTFrameGetVisibleStringRange(frameRef);
    currentRange.location += currentRange.length;
    currentRange.length = 0;
    CFRelease(frameRef);

    return currentRange;
}


- (void)drawPageNumber:(NSInteger)pageNum
{
    NSString* pageString = [NSString stringWithFormat:NSLocalizedString(@"Page", nil), pageNum];
    UIFont* theFont = [UIFont systemFontOfSize:12];
    CGSize maxSize = CGSizeMake(kDefaultPageWidth, 72);

    CGSize pageStringSize = [pageString sizeWithFont:theFont
                                   constrainedToSize:maxSize
                                       lineBreakMode:UILineBreakModeClip];
    CGRect stringRect = CGRectMake(((kDefaultPageWidth - pageStringSize.width) / 2.0),
                                   720.0 + ((72.0 - pageStringSize.height) / 2.0) ,
                                   pageStringSize.width,
                                   pageStringSize.height);

    [pageString drawInRect:stringRect withFont:theFont];
}

我想知道如何在描述结束后立即在页面末尾绘制图像。

我用这种方式画了标题:

-(void)drawHeader{
    NSString *headerString = nameString;
    UIFont* theFont = [UIFont boldSystemFontOfSize:15];
    CGSize maxSize = CGSizeMake(kDefaultPageWidth, 72);

    CGSize pageStringSize = [headerString sizeWithFont:theFont constrainedToSize:maxSize lineBreakMode:UILineBreakModeClip];
    CGRect stringRect = CGRectMake(22,22,pageStringSize.width,pageStringSize.height);

    [headerString drawInRect:stringRect withFont:theFont];
}

它会显示在每个页面的开头。

现在我不知道如何在内容(描述)之后绘制图像!

任何帮助都非常感谢!

4 个答案:

答案 0 :(得分:4)

在上下文中绘制pdf就像在画布中绘图一样。

绘制动态文本和图像的最佳方法是创建和使用绘制方法,返回用于在页面中绘制的高度,并简单地保留变量以通过递增计算下一个绘图orgin y位置返回值。还有一个单独的偏移量变量来检查页面框架。

要将图像绘制到pdf上下文中,您可以使用以下示例。您还可以通过Core Graphics渲染CGImage,但是您必须考虑画布的旋转(CGContext),因为那些因为Core Graphics中的坐标原点位于右下角,所以将以颠倒的方式显示(翻转)。

UIImage *gymLogo=[UIImage imageNamed:@"logo.png"];
CGPoint drawingLogoOrigin = CGPointMake(5,5);
[gymLogo drawAtPoint:drawingLogoOrigin];

快乐编码:)

答案 1 :(得分:1)

首先在pdf_tutorialViewController.h文件

中创建自定义方法
- (void)drawImage:(UIImage *)img  atRect:(CGRect)rect inContext:(CGContextRef)ctx;

/////////////// pdf_tutorialViewController.m file //////////

并添加UIImage并在您的方法结尾处调用drawImage:atRect:inContext:方法。

- (CFRange)renderPage:(NSInteger)pageNum withTextRange:(CFRange)currentRange
       andFramesetter:(CTFramesetterRef)framesetter
{
  ////////////////////////////////////////////////////////////////////////////////////
       UIImage *logoimg = [UIImage imageNamed:@"1.png"];
       [self drawImage:logoimg atRect:CGRectMake("Your Size") inContext:currentContext];
       return currentRange;
  ////////////////////////////////////////////////////////////////////////////////////
} 

并添加

代码
- (void)drawImage:(UIImage *)img  atRect:(CGRect)rect inContext:(CGContextRef)ctx
{
    UIImage *myImage = (UIImage *)img;
    [myImage drawInRect:rect];
    //[myImage release];
}

此代码可能对您有所帮助:)

谢谢

答案 2 :(得分:1)

这里是UIView的子类,可以做你想要的......

您可以将其放在UIScrollView中。在超级浏览-sizeThatFits:期间,请致电-layoutSubviews以获取正确的框架尺寸。 (也适用于您的封闭滚动视图&#39> contentSize 。)

请注意,我在UILabel上添加了一个类别,该类别返回-sizeThatFits:的合理大小,您可能希望提供自己的实现。

<强> View.h

#import <UIKit/UIKit.h>

@interface View : UIView
@property ( nonatomic, strong, readonly ) UILabel * descriptionLabel ;
@property ( nonatomic, strong, readonly ) UILabel * nameLabel ;
@property ( nonatomic, strong, readonly ) UIImageView * pdfImageView ;

@property ( nonatomic ) CGPDFDocumentRef pdf ;

@end

<强> View.m

#import "View.h"

@implementation UILabel (SizeThatFits)
-(CGSize)sizeThatFits:(CGSize)fitSize
{
    return [ self.text sizeWithFont:self.font constrainedToSize:fitSize ] ;
}
@end

@interface View ()
@property ( nonatomic, strong, readonly ) UIImage * pdfImage ;
@end

@implementation View
@synthesize descriptionLabel = _descriptionLabel ;
@synthesize nameLabel = _nameLabel ;
@synthesize pdfImageView = _pdfImageView ;
@synthesize pdfImage = _pdfImage ;

-(void)dealloc
{
    CGPDFDocumentRelease( _pdf ) ;
}

-(CGSize)sizeThatFits:(CGSize)size
{
    CGSize fitSize = (CGSize){ size.width, CGFLOAT_MAX } ;

    CGSize result = { size.width, 0 } ;
    result.height = [ self.headerLabel sizeThatFits:fitSize ].height
        + [ self.label sizeThatFits:fitSize ].height
        + self.pdfImage.size.height * fitSize.width / self.pdfImage.size.width ;
    return result ;
}

-(void)layoutSubviews
{
    CGRect bounds = self.bounds ;
    CGRect slice ;

    CGRectDivide( bounds, &slice, &bounds, [ self.headerLabel sizeThatFits:bounds.size ].height, CGRectMinYEdge ) ;
    self.headerLabel.frame = slice ;

    CGRectDivide( bounds, &slice, &bounds, [ self.label sizeThatFits:bounds.size ].height, CGRectMinYEdge ) ;
    self.label.frame = slice ;

    self.pdfImageView.frame = bounds ;
}

-(void)setPdf:(CGPDFDocumentRef)pdf
{
    CGPDFDocumentRelease( _pdf ) ;
    _pdf = CGPDFDocumentRetain( pdf ) ;
    _pdfImage = nil ;
}

-(UILabel *)descriptionLabel
{
    if ( !_descriptionLabel )
    {
        UILabel * label = [[ UILabel alloc ] initWithFrame:CGRectZero ] ;
        label.numberOfLines = 0 ;
        //
        // ... configure label here
        //
        [ self addSubview:label ] ;
        _descriptionLabel = label ;
    }
    return _descriptionLabel ;
}

-(UILabel *)nameLabel
{
    if ( !_nameLabel )
    {
        UILabel * label = [[ UILabel alloc ] initWithFrame:CGRectZero ] ;
        label.numberOfLines = 0 ;
        //
        // ... configure label here
        //
        [ self addSubview:label ] ;
        _nameLabel = label ;
    }
    return _nameLabel ;
}

-(UIView *)pdfImageView
{
    if ( !_pdfImageView )
    {
        UIImageView * imageView = [[ UIImageView alloc ] initWithFrame:CGRectZero ] ;
        [ self addSubview:imageView ] ;
        _pdfImageView = imageView ;
    }

    return _pdfImageView ;
}

-(UIImage *)pdfImage
{
    if ( !_pdfImage )
    {
        CGPDFPageRef page = CGPDFDocumentGetPage( self.pdf, 1 ) ; // 1 indexed
        CGRect mediaBox = CGPDFPageGetBoxRect( page, kCGPDFMediaBox ) ;
        UIGraphicsBeginImageContextWithOptions( mediaBox.size, NO, self.window.screen.scale ) ;

        CGContextRef c = UIGraphicsGetCurrentContext() ;
        CGContextScaleCTM( c, 1.0f, -1.0f ) ;
        CGContextTranslateCTM( c, 0.0, -mediaBox.size.height ) ;

        CGContextDrawPDFPage( c, page ) ;

        _pdfImage = UIGraphicsGetImageFromCurrentImageContext() ;

        self.pdfImageView.image = _pdfImage ;

        UIGraphicsEndImageContext() ;
    }

    return _pdfImage ;
}

@end

如果您需要页码页脚,可以按照相同的模式在底部添加另一个UILabel。

答案 3 :(得分:0)

NSString *fileName = @"myInfo.pdf";
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *pdfFileName = [documentsDirectory stringByAppendingPathComponent:fileName];

if ([passwordString length]) {
    NSDictionary *dictionary = [[NSDictionary alloc] initWithObjectsAndKeys:passwordString, kCGPDFContextOwnerPassword, passwordString, kCGPDFContextUserPassword, kCFBooleanFalse, kCGPDFContextAllowsCopying, kCFBooleanFalse, kCGPDFContextAllowsPrinting,  nil]; // Providing Password Protection for PDF File
    UIGraphicsBeginPDFContextToFile(pdfFileName, CGRectZero, dictionary);
    [dictionary release];
} else {
    UIGraphicsBeginPDFContextToFile(pdfFileName, CGRectZero, nil);
}

UIGraphicsBeginPDFPageWithInfo(CGRectMake(0, 0, 612.0, heightOfView), nil); //612,792 Width  & Height of the pdf page which we want to generate.
NSString *pngPath = [documentsDirectory stringByAppendingPathComponent:[NSString stringWithFormat:@"%d.png", 123]];
UIImage *pngImage = [UIImage imageWithContentsOfFile:pngPath];

[pngImage drawInRect:CGRectMake((612 - self.frame.size.width) / 2, 0, self.frame.size.width, heightOfView)]; // Size of the image we want to draw in pdf file.
UIGraphicsEndPDFContext();