iOS开发笔记——PDF的显示和浏览

今天的任务是：在iOS上加载显示pdf文件。

方法一：利用webview

-(void)loadDocument:(NSString *)documentName inView:(UIWebView *)webView { NSString *path = [[NSBundle mainBundle] pathForResource:documentName ofType:nil]; NSURL *url = [NSURL fileURLWithPath:path]; NSURLRequest *request = [NSURLRequest requestWithURL:url]; [webView loadRequest:request]; }

利：1.实现简单

2.还是实现简单

弊：1.仅能浏览，拿不到任何回调，safari不会鸟任何人。

2.固定竖版拖动，想实现翻页动效果就扒瞎

下面的方法可以解决webview 显示pdf的弊，相对的，要付出一些汗水作为代价了。

方法二：利用CGContextDrawPDFPage

CGPDFDocumentRef GetPDFDocumentRef(NSString *filename) { CFStringRef path; CFURLRef url; CGPDFDocumentRef document; size_t count; path = CFStringCreateWithCString (NULL, [filename UTF8String], kCFStringEncodingUTF8); url = CFURLCreateWithFileSystemPath (NULL, path, kCFURLPOSIXPathStyle, 0); CFRelease (path); document = CGPDFDocumentCreateWithURL (url); CFRelease(url); count = CGPDFDocumentGetNumberOfPages (document); if (count == 0) { printf("[%s] needs at least one page!\n", [filename UTF8String]); return NULL; } else { printf("[%ld] pages loaded in this PDF!\n", count); } return document; } void DisplayPDFPage (CGContextRef myContext, size_t pageNumber, NSString *filename) { CGPDFDocumentRef document; CGPDFPageRef page; document = GetPDFDocumentRef (filename); page = CGPDFDocumentGetPage (document, pageNumber); CGContextDrawPDFPage (myContext, page); CGPDFDocumentRelease (document); }

这样显示出来的pdf单页是倒立的，Quartz坐标系和UIView坐标系不一样所致，调整坐标系，使pdf正立：

CGContextRef context = UIGraphicsGetCurrentContext(); CGContextTranslateCTM(context, 80, self.frame.size.height-60); CGContextScaleCTM(context, 1, -1);

配合iOS5强大的UIPageViewController实现翻页浏览

- (PDFViewController *)viewControllerAtIndex:(NSUInteger)index { //Return the PDFViewController for the given index. if (([self.pagePDF count] == 0 )|| (index > [self.pagePDF count]) ) { return nil; } //Create a new view controller and pass suitable data. PDFViewController *dataViewController = [[PDFViewController alloc]initWithNibName:@"PDFViewController" bundle:nil]; //dataViewController.pdfview = [self.pagePDF objectAtIndex:index]; dataViewController.pdfview = [[PDFView alloc]initWithFrame:self.view.frame atPage:index]; [dataViewController.view addSubview:dataViewController.pdfview]; NSLog(@"index = %d",index); return dataViewController; } - (NSUInteger) indexOfViewController:(PDFViewController *)viewController { return [self.pagePDF indexOfObject:viewController.pdfview]; } - (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerBeforeViewController:(UIViewController *)viewController { NSUInteger index = [self indexOfViewController:(PDFViewController *)viewController]; if ((index == 0 ) || (index == NSNotFound)){ return nil; } index--; return [self viewControllerAtIndex:index]; } - (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerAfterViewController:(UIViewController *)viewController { NSUInteger index = [self indexOfViewController:(PDFViewController *)viewController]; if (index == NSNotFound) { return nil; } index++; if (index == [self.pagePDF count]){ return nil; } return [self viewControllerAtIndex:index]; }

后续将完成涂鸦pdf后保存创建新pdf的功能。

特别感谢cclv的帮助和指点。