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Soulstorm
May 4, 2011, 02:03 AM
I am trying to create a basic PDF viewer for iOS, and I am pretty much stuck. I only want it to be able to view PDFs and jump to a specific page.

Here is what I have done so far:

#import "SFPDFViewerController.h"
#import <QuartzCore/QuartzCore.h>

@implementation SFPDFViewerController
@synthesize currentPageIndex;

- (void)viewDidLoad
{
currentPageIndex = 1;

myDocumentRef = CGPDFDocumentCreateWithURL((CFURLRef)[NSURL URLWithString:@"file:///Users/soulstorm/Desktop/Basic%20UNIX%20Tutorial.pdf"]);
myPageRef = CGPDFDocumentGetPage(myDocumentRef, currentPageIndex);
//CGRect pageRect = CGRectIntegral(CGPDFPageGetBoxRect(myPageRef, kCGPDFCropBox));
CGRect pageRect = self.view.bounds;

CATiledLayer *tiledLayer = [CATiledLayer layer];
tiledLayer.delegate = self;
tiledLayer.tileSize = CGSizeMake(200.0, 200.0);
tiledLayer.levelsOfDetail = 1000;
tiledLayer.levelsOfDetailBias = 1000;
tiledLayer.frame = pageRect;

myContentView = [[UIView alloc] initWithFrame:pageRect];
[myContentView.layer addSublayer:tiledLayer];

CGRect viewFrame = self.view.frame;
viewFrame.origin = CGPointZero;
viewFrame.size.height-= 44;

scrollView = [[UIScrollView alloc] initWithFrame:viewFrame];
scrollView.delegate = self;
scrollView.contentSize = pageRect.size;
scrollView.maximumZoomScale = 3.0;
[scrollView addSubview:myContentView];

[self.view addSubview:scrollView];

[self.view setBackgroundColor:[UIColor whiteColor]];
[scrollView setBackgroundColor:[UIColor whiteColor]];
}

- (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
// e.g. self.myOutlet = nil;
}

- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView
{
return myContentView;
}

- (void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx
{
NSLog(@"draw layer...");
CGContextSetRGBFillColor(ctx, 1.0, 1.0, 1.0, 1.0);
CGContextFillRect(ctx, CGContextGetClipBoundingBox(ctx));
CGContextTranslateCTM(ctx, 0.0, layer.bounds.size.height);
CGContextScaleCTM(ctx, 1.0, -1.0);
CGContextConcatCTM(ctx, CGPDFPageGetDrawingTransform(myPageRef, kCGPDFCropBox, layer.bounds, 0, true));
CGContextDrawPDFPage(ctx, myPageRef);
}

#pragma mark - Functions
- (IBAction)goToNextPage:(id)sender
{
[self displayNextPage];
}
- (IBAction)goToPreviewsPage:(id)sender
{
[self displayPreviewsPage];
}

- (void)displayNextPage
{
currentPageIndex++;
[self reloadCurrentPage];
}
- (void)displayPreviewsPage
{
currentPageIndex--;
[self reloadCurrentPage];
}
- (void)reloadCurrentPage
{
NSLog(@"reloading current page... %i", currentPageIndex);
myPageRef = CGPDFDocumentGetPage(myDocumentRef, currentPageIndex);
//[self.view setNeedsDisplay];
//[self.view.layer setNeedsDisplay];
//[myContentView.layer setNeedsDisplay];
}
#pragma mark -
- (void)dealloc
{
[myContentView release];
myContentView = nil;
CGPDFDocumentRelease(myDocumentRef);
myDocumentRef = NULL;
myPageRef = NULL;
[super dealloc];
}
@end

The above code displays the first page of the PDF corectly, but when I try to go to the next page, it will remain on the first one, and sometimes when zooming I can see parts of the second page.

Can anyone point me in the right direction?



jnoxx
May 4, 2011, 02:53 AM
Look for the library called Leaves, it's on google groups called, Leaves-Developers :>

camerono
May 5, 2011, 07:45 AM
Seems to me that what you're attempting is already provided for you in QuickLook (http://developer.apple.com/library/ios/ipad/#documentation/FileManagement/Conceptual/DocumentInteraction_TopicsForIOS/Articles/UsingtheQuickLookFramework.html) (introduced in iOS 4.1, I believe)
:apple:

Soulstorm
May 5, 2011, 10:55 AM
Seems to me that what you're attempting is already provided for you in QuickLook (http://developer.apple.com/library/ios/ipad/#documentation/FileManagement/Conceptual/DocumentInteraction_TopicsForIOS/Articles/UsingtheQuickLookFramework.html) (introduced in iOS 4.1, I believe)
:apple:

Indeed, but I think that Quicklook does not provide jumping to a specific page inside a document...

Shawnpk
May 5, 2011, 11:51 AM
Indeed, but I think that Quicklook does not provide jumping to a specific page inside a document...

I could be wrong, but isn't this how Apple implements PDF viewing in iBooks? And in iBooks there is a way to jump to a specific page. More than one way actually.

jnoxx
May 6, 2011, 02:08 AM
I'm interested in a basic tutorial from this QuickLook thing, could allways be usefull ;)
Thanksies! :)