scrollview 图片放大 捏合 瓦片地图 相关注意事项

就职文博公司要为博物馆做APP 涉及到瓦片地图的编写 在这里总结一些开发中遇到的问题 (将会不断更新 也是学习阶段)

着急写项目的同学 可以直接看code4上现成的瓦片地图代码：http://www.code4app.com/ios/Tiled-Scroll-View/4fba3fd66803fa8413000000

1. 首先实现利用scrollview实现图片的缩放： 需要设置

maximumZoomScale;     // default is 1.0. must be > minimum zoom scale to enable zooming  *****只有设置了这个属性值大于1.0 才能实现缩放效果

下面上代码

//.h 文件

#import <UIKit/UIKit.h>

@interface HDMapView : UIScrollView <UIScrollViewDelegate>

-(instancetype)initWithFrame:(CGRect)frame andContentSize:(CGSize)contentSize;

-(void)setMapImage:(UIImage*)image;

@end

//.m 文件

#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=;

        self.frame = frame;

        self.delegate = self;

        self.contentSize = contentSize;

        self.myImageView = [[UIImageView alloc]initWithFrame:CGRectMake(, , contentSize.width, contentSize.height)];

        self.myImageView.userInteractionEnabled = YES;

        [self addSubview:self.myImageView];

        UITapGestureRecognizer *twiceTap = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(tapTwice)];

        twiceTap.numberOfTapsRequired = ;

        twiceTap.numberOfTouchesRequired = ;

        [self.myImageView addGestureRecognizer:twiceTap];

    }

    return self;

}

-(void)tapTwice

{

    if (self.zoomScale > ) {

        [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];

}