我正在使用下面的代码生成 PDF,但它会导致内存泄漏,有人可以帮忙吗?代码如下。
- (void)drawText:(NSString*)textToDraw inFrame:(CGRect)frameRect {
NSMutableAttributedString *string = [[[NSMutableAttributedString alloc]
initWithString:textToDraw] autorelease];
// make a few words bold
CTFontRef helveticaBold = CTFontCreateWithName(CFSTR("Helvetica-Bold"), 8.0, NULL);
[string addAttribute:(id)kCTFontAttributeName
value:(id)helveticaBold
range:NSMakeRange(0, [string length])];
// add some color.
if (_flag == 1) {
[string addAttribute:(id)kCTForegroundColorAttributeName
value:(id)[UIColor whiteColor].CGColor
range:NSMakeRange(0, [string length])];
} else {
[string addAttribute:(id)kCTForegroundColorAttributeName
value:(id)[UIColor blackColor].CGColor
range:NSMakeRange(0, [string length])];
}
// layout master
CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString((CFAttributedStringRef)string);
CGMutablePathRef framePath = CGPathCreateMutable();
CGPathAddRect(framePath, NULL, frameRect);
// Get the frame that will do the rendering.
CFRange currentRange = CFRangeMake(0, 0);
CTFrameRef frameRef = CTFramesetterCreateFrame(framesetter, currentRange, framePath, NULL);
CGPathRelease(framePath);
// 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);
CGContextSetRGBFillColor(currentContext, 0, 0, 0, 1.0);
// Core Text draws from the bottom-left corner up, so flip
// the current transform prior to drawing.
CGContextTranslateCTM(currentContext, 0, frameRect.origin.y*2);
CGContextScaleCTM(currentContext, 1.0, -1.0);
// Draw the frame.
CTFrameDraw(frameRef, currentContext);
CGContextScaleCTM(currentContext, 1.0, -1.0);
CGContextTranslateCTM(currentContext, 0, (-1)*frameRect.origin.y*2);
CFRelease(frameRef);
//CFRelease(stringRef);
CFRelease(framesetter);
}
我在生成时多次调用此函数
PDF,每次这都会导致内存泄漏。