Notes for scrollview Image zoom-in and Kneading tile maps, scrollview tiles

Notes for scrollview Image zoom-in and Kneading tile maps, scrollview tiles

The inaugural Wenbo company wants to write tile maps for the museum APP. Here we will summarize some problems encountered in the development process (which will be updated continuously and will also be the learning stage)

Anxious to write the project can directly look at code4 on the ready-made tile map code: http://www.code4app.com/ios/Tiled-Scroll-View/4fba3fd66803fa8413000000

1. First, use scrollview to scale the image: You need to set

MaximumZoomScale; // default is 1.0. must be> minimum zoom scale to enable zooming ***** the zoom effect can be achieved only when the value of this attribute is set to be greater than 1.0

The code below

//. H file # import <UIKit/UIKit. h> @ interface HDMapView: UIScrollView <UIScrollViewDelegate>-(instancetype) initWithFrame :( CGRect) frame andContentSize :( CGSize) contentSize;-(void) setMapImage :( UIImage *) image; @ end //. m file # import "HDMapView. h "@ interface HDMapView () @ property (strong, nonatomic) UIImageView * myImageView; @ end @ implementation HDMapView-(instancetype) initWithFrame :( CGRect) frame andContentSize :( CGSize) contentSize {self = [super initWithFrame: frame]; if (self) {self. maximumZoomScale = 17; self. frame = frame; self. delegate = self; self. contentSize = contentSize; self. myImageView = [[UIImageView alloc] initWithFrame: CGRectMake (0, 0, contentSize. width, contentSize. height)]; self. myImageView. userInteractionEnabled = YES; [self addSubview: self. myImageView]; UITapGestureRecognizer * twiceTap = [[UITapGestureRecognizer alloc] initWithTarget: self action: @ selector (tapTwice)]; twiceTap. numberOfTapsRequired = 2; twiceTap. numberOfTouchesRequired = 1; [self. myImageView addGestureRecognizer: twiceTap];} return self;}-(void) tapTwice {if (self. zoomScale> 3) {[self setZoomScale: 1.0 animated: YES];} else {CGFloat a = self. zoomScale; a ++; [self setZoomScale: a animated: YES] ;}}-(void) setMapImage :( UIImage *) image {self. myImageView. image = image ;}# pragma mark-UIScrollViewDelegate-(UIView *) viewForZoomingInScrollView :( UIScrollView *) scrollView {return self. myImageView;}-(void) scrollViewDidEndZooming :( UIScrollView *) scrollView withView :( UIView *) view atScale :( CGFloat) scale {[self setZoomScale: scale animated: YES];}