ScrollView for ipad Image scrolling and scaling through gestures

 

When previewing an image on an ipad, if we want to scale and scroll (similar to google maps), we need to use ScrollView

 

------- View Controller definition:

 

@ Interface TestBedViewController: UIViewController <UIScrollViewDelegate>

 

{

 

UIImage * weathermap;

 

}

 

@ Property (retain) UIImage * weathermap;

 

@ End

 

 

@ Implementation TestBedViewController

 

@ Synthesize weathermap;

 

// Specify the Image in all the scrollviews when using the zoom gesture.

 

-(UIView *) viewForZoomingInScrollView :( UIScrollView *) scrollView

 

{

 

Return [self. view viewwithtagag: 201];

 

}

 

 

/*

 

-(Void) scrollViewDidEndZooming :( UIScrollView *) scrollView withView :( UIView *) view atScale :( float) scale

 

{

 

}

 

*/

 

 

-(Void) viewDidLoad

 

{

 

 

// Create a scroll view and set the size and height of the proxy object px py width

 

UIScrollView * sv = [[UIScrollView alloc] initWithFrame: CGRectMake (0.0f, 0.0f, 3200000f, 284.0f)] autorelease];

 

Sv. contentSize = self. weathermap. size; // The UIImage object to be scaled.

 

Sv. delegate = self; // sets the proxy object

 

 

// Create an image object

 

UIImageView * iv = [[UIImageView alloc] initWithImage: self. weathermap] autorelease];

 

Iv. userInteractionEnabled = YES;

 

Iv. tag= 201;

 

 

// Calculate the zoom Value

 

Float minzoomx = sv. frame. size. width/self. weathermap. size. width;

 

Float minzoomy = sv. frame. size. height/self. weathermap. size. height;

 

Sv. minimumZoomScale = MIN (minzoomx, minzoomy); // the minimum scale to the current ScrollView

 

Sv. maximumZoomScale = 3.0f; // scale up to three times the image size.

 

 

// Add an image in scorllView

 

[Sv addSubview: iv];

 

[Self. view addSubview: sv];

 

}

 

@ End

 

Author sdhjob