Load PDF in UIViewcontroller

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Load PDF in UIViewcontroller

Hello!

I am creating a simple PDF reader. All of the sample codes that i saw i had to tap a button to open the pdf. But what i really want is to open the pdf file when te app runs, without tapping a button.

This is my viewDidLoad code in ViewController.m:

- (void)viewDidLoad

{

[superviewDidLoad];

NSString *path = [[NSBundlemainBundle] pathForResource:@"399_KIT_ELEITORAL_BX_01"ofType:@"pdf"];

PageViewController *page = [[PageViewControlleralloc] initWithPDFAtPath:path];

[selfpresentViewController:page animated:YEScompletion:NULL];

}

When i run the app, it doesn`t show the pdf.

Thank you!

Posted on Feb 3, 2014 4:58 AM

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Answer 1

msuper69

Level 6

8,705 points

Feb 3, 2014 5:05 AM in response to LeoRegin

Put that code in ViewWillAppear.

The view is not visible in viewDidLoad; viewDidLoad tells you that the view has been loaded into memory.

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Answer 2

LeoRegin Author

Level 1

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Feb 3, 2014 5:15 AM in response to msuper69

I put the code in ViewWillAppear, but it still doesn`t appear:

This is the whole code:

@interfaceViewController ()

@end

@implementation ViewController

- (void)viewDidLoad

{

[superviewDidLoad];

}

- (void)viewWillAppear

{

NSString *path = [[NSBundlemainBundle] pathForResource:@"399_KIT_ELEITORAL_BX_01"ofType:@"pdf"];

PageViewController *page = [[PageViewControlleralloc] initWithPDFAtPath:path];

[selfpresentViewController:page animated:YEScompletion:NULL];

}

- (void)didReceiveMemoryWarning

{

[superdidReceiveMemoryWarning];

// Dispose of any resources that can be recreated.

}

@end

Thank you!

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Answer 3

msuper69

Level 6

8,705 points

Feb 3, 2014 5:15 AM in response to LeoRegin

Where is [super viewWillAppear] in viewWillAppear?

That is required whenever you subclass UIViewController.

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Answer 4

LeoRegin Author

Level 1

0 points

Feb 3, 2014 5:23 AM in response to msuper69

- (void)viewWillAppear

{

[super viewWillAppear];

NSString *path = [[NSBundlemainBundle] pathForResource:@"399_KIT_ELEITORAL_BX_01"ofType:@"pdf"];

PageViewController *page = [[PageViewControlleralloc] initWithPDFAtPath:path];

[selfpresentViewController:page animated:YEScompletion:NULL];

}

It says that:

No visible @interface for 'UIViewController' declares the selector 'viewWillAppear'

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Answer 5

msuper69

Level 6

8,705 points

Feb 3, 2014 5:25 AM in response to LeoRegin

The method declaration for viewWillAppear is viewWillAppear:animated where animated is a BOOL.

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Answer 6

LeoRegin Author

Level 1

0 points

Feb 3, 2014 5:30 AM in response to msuper69

Two errors appear...

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Answer 7

msuper69

Level 6

8,705 points

Feb 3, 2014 5:33 AM in response to LeoRegin

You have to use a BOOL in place of animated. For example, [super viewWillAppear:YES];

You've also left off the ending semi-colon which is a syntax requirement of Objective-C.

Statements end with a semi-colon in Objective-C and that line is missing the semi-colon.

You really need to review the basics of Objective-C as these are all very basic concepts.

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Answer 8

LeoRegin Author

Level 1

0 points

Feb 3, 2014 5:39 AM in response to msuper69

I'm sorry for the mistakes, i am new im Objective-C, but i think i will only learn programming lwhile i do this. I apreciate your help!

This is the new code:

- (void)viewWillAppear

{

[superviewWillAppear:YES];

NSString *path = [[NSBundlemainBundle] pathForResource:@"399_KIT_ELEITORAL_BX_01"ofType:@"pdf"];

PageViewController *page = [[PageViewControlleralloc] initWithPDFAtPath:path];

[selfpresentViewController:page animated:YEScompletion:NULL];

}

But it still doesn't show the pdf...

I need your help to finish this task.

Thank you!

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Answer 9

msuper69

Level 6

8,705 points

Feb 3, 2014 5:44 AM in response to LeoRegin

Try using some NSLog statements placed strategically in your code to display some of the objects.

For instance, NSLog(@"viewWillAppear path=%@", path); (after your NSString *path ...)

What does this statement output?

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Answer 10

LeoRegin Author

Level 1

0 points

Feb 3, 2014 5:51 AM in response to msuper69

The original project was to tap a button with a IBAction to load the pdf.

But now i'm trying to open it when the app runs, without any button.
So i copy the code under -(void)openPDF and paste it in -(void)viewWillAppear, because it doesn't need to be an action anymore, right?

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