Question

我正在iOS应用中动态构建PDF文档。我试图将HTML格式的字符串转换为NSAttributedString，然后将其放在我的PDF文档页面上。

如果我将字符串视为普通的NSString，我可以设置它的框架并将其放置在页面的任何位置（字符串中包含的html标签）。

如果我使用initWithString创建NSAttributedString，我也可以将结果属性字符串放在页面的任何位置。

如果我使用

将字符串转换为NSAttributedString

NSAttributedString initWithData:options:documentAttributes:error:

转换工作完美，标签转换为属性。但是当我尝试将字符串的框架放在页面上时，文本会被剪切，因为我将框架向下移动并从0,0向右移动。我可以将文本向下移动20个点，然后逐行剪切文本。当所有文本从页面上消失时，我可以向右移动框架，直到原点大于宽度。

代码：

#pragma mark - === PDF BUILD Methods === -

- (void)buildPDF {

self.pdfPageSize = CGSizeMake(850.0, 1100.0);
UIFont *titleFont = [UIFont fontWithName:@"Dispatch-Bold" size:24.0];
UIFont *bodyFont = [UIFont systemFontOfSize:18.0];

// Open a new PDF dcument
[self setupPDFDocumentNamed:@"testPDF" Width:self.pdfPageSize.width Height:self.pdfPageSize.height];

//cover page
[self beginPDFPage];

NSString *title = [NSString stringWithFormat:@"How to Tie a %@", self.knot.knotName];
[self addText:title withFrame:CGRectMake(0, 10, 850, 30) font:titleFont alignment:NSTextAlignmentCenter];

[self addLineWithFrame:CGRectMake(10, 40, 830, 2) withColor:[CSCColors favoritesColor]];

NSString *imageName = [NSString stringWithFormat:@"%@_0", self.knot.knotID];
[self addImage:[UIImage imageNamed:imageName] atPoint:CGPointMake(50, 50)];

// addText method works, but addHTML method does not
//[self addText:self.knot.knotDescription withFrame:CGRectMake(400, 50, 300, 500) font:bodyFont alignment:NSTextAlignmentLeft];
[self addHTMLText:self.knot.knotDescription withFrame:CGRectMake(400, 50, 300, 500) font:bodyFont alignment:NSTextAlignmentLeft];

//close out the PDF
[self finishPDF];

}

-(void)setupPDFDocumentNamed:(NSString*)name Width:(float)width Height:(float)height {
self.pdfPageSize = CGSizeMake(width, height);

NSString *newPDFName = [NSString stringWithFormat:@"%@.pdf", name];

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];

NSString *pdfPath = [documentsDirectory stringByAppendingPathComponent:newPDFName];

UIGraphicsBeginPDFContextToFile(pdfPath, CGRectZero, nil);
}

- (void)beginPDFPage {
UIGraphicsBeginPDFPageWithInfo(CGRectMake(0, 0, self.pdfPageSize.width, self.pdfPageSize.height), nil);
}

- (void)finishPDF {
UIGraphicsEndPDFContext();
}

- (void)addText:(NSString*)text withFrame:(CGRect)frame font:(UIFont*)font alignment:(NSTextAlignment)alignment{

// Set up character and paragraph attributes
UIColor * cscBlueColor = [UIColor colorWithRed:0.0 green:0.53 blue:0.8 alpha:1.0];

NSMutableParagraphStyle *paraStyle = [[NSMutableParagraphStyle alloc] init];
paraStyle.lineBreakMode = NSLineBreakByWordWrapping;
paraStyle.alignment = alignment;

//Calculate frame
NSDictionary *attr = @{NSFontAttributeName:font};

CGRect textRect = [text boundingRectWithSize:frame.size options:NSStringDrawingUsesLineFragmentOrigin attributes:attr context:nil];

CGSize stringSize = textRect.size;

float textWidth = frame.size.width;

if (textWidth < stringSize.width)
    textWidth = stringSize.width;
if (textWidth > _pdfPageSize.width)
    textWidth = _pdfPageSize.width - frame.origin.x;

CGRect renderingRect = CGRectMake(frame.origin.x, frame.origin.y, textWidth, stringSize.height);

NSDictionary *renderingAttr = @{NSParagraphStyleAttributeName:paraStyle, NSFontAttributeName:font, NSForegroundColorAttributeName:cscBlueColor};
[text drawInRect:renderingRect withAttributes:renderingAttr];

}

- (void)addHTMLText:(NSString*)text withFrame:(CGRect)frame font:(UIFont *)font alignment:(NSTextAlignment)alignment{

NSMutableAttributedString *myString = [[NSMutableAttributedString alloc] initWithData:[text dataUsingEncoding:NSUTF8StringEncoding]
                                                                              options:@{NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType,
                                                                          NSCharacterEncodingDocumentAttribute: [NSNumber numberWithInt:NSUTF8StringEncoding]}
                                                                   documentAttributes:nil
                                                                                error:nil];
NSRange myRange;
myRange.location = 0;
myRange.length = myString.length;

// Set up character and paragraph attributes
UIColor * cscBlueColor = [UIColor colorWithRed:0.0 green:0.53 blue:0.8 alpha:1.0];

NSMutableParagraphStyle *paraStyle = [[NSMutableParagraphStyle alloc] init];
paraStyle.lineBreakMode = NSLineBreakByWordWrapping;
paraStyle.paragraphSpacing = 10.0f;
paraStyle.alignment = alignment;

NSDictionary *renderingAttr = @{NSParagraphStyleAttributeName:paraStyle, NSFontAttributeName:font, NSForegroundColorAttributeName:cscBlueColor};
[myString addAttributes:renderingAttr range:myRange];


//Calculate frame
NSStringDrawingContext *sdctx = [[NSStringDrawingContext alloc] init];
CGRect textRect = [myString boundingRectWithSize:CGSizeMake(frame.size.width, CGFLOAT_MAX) options:NSStringDrawingUsesLineFragmentOrigin context:sdctx];

CGSize stringSize = textRect.size;

float textWidth = frame.size.width;

if (textWidth < stringSize.width)
    textWidth = stringSize.width;
if (textWidth > _pdfPageSize.width)
    textWidth = _pdfPageSize.width - frame.origin.x;

CGRect renderingRect = CGRectMake(frame.origin.x, frame.origin.y, textWidth, stringSize.height);

// fill rect so we can visualize the frame
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(context, [UIColor lightGrayColor].CGColor);
CGContextFillRect(context, renderingRect);

//[myString drawInRect:renderingRect];
[myString drawWithRect:renderingRect options:NSStringDrawingUsesLineFragmentOrigin context:sdctx];

}


- (void)addImage:(UIImage*)image atPoint:(CGPoint)point {
CGRect imageFrame = CGRectMake(point.x, point.y, image.size.width, image.size.height);
[image drawInRect:imageFrame];
}

- (void)addLineWithFrame:(CGRect)frame withColor:(UIColor*)color {
CGContextRef currentContext = UIGraphicsGetCurrentContext();

CGContextSetStrokeColorWithColor(currentContext, color.CGColor);

// this is the thickness of the line
CGContextSetLineWidth(currentContext, 2);

CGPoint startPoint = frame.origin;
CGPoint endPoint = CGPointMake(frame.origin.x + frame.size.width, frame.origin.y);

CGContextBeginPath(currentContext);
CGContextMoveToPoint(currentContext, startPoint.x, startPoint.y);
CGContextAddLineToPoint(currentContext, endPoint.x, endPoint.y);

CGContextClosePath(currentContext);
CGContextDrawPath(currentContext, kCGPathFillStroke);

}

有什么想法吗？

屏幕上限：

对于前两个屏幕上限，我使用了

NSAttributedString initWithData:options:documentAttributes:error:

生成属性字符串

在第一个框架中，框架设置为{400,50,300,500}并且文本被完全剪裁。

在第二帧中，{400,50,401,500}显示文字，但前两行文字被剪裁在顶部。如果我将框架移动到20，则所有线条都可见。

在最后一个屏幕截图中，我只使用initWithString来获取属性字符串，除了HTML没有转换为属性外，一切正常。

grey box is frame of text enter image description here

我还清理了HTML字符串，以确保标记和类调用没有引入一些奇怪的属性。清理后的字符串具有相同的结果：

<html><body><p>Landlubbers need not apply. The Sheet Bend is an essential knot to know and one of the first knots taught to new sailors. It is very fast to tie and is useful when joining two ropes of different diameters.</p><p>Also known as Becket bend (when made fast to an eye instead of a loop), the Sheet Bend is often considered one of the most essential knots and is related in structure to the bowline. If the two free ends are not on the same side of the knot, the result is a left-handed sheet bend of significantly reduced strength.</p></body></html>

由于

将NSAttributedString放入PDF中的问题

0 个答案: