Simple image browser [zoomed images, sliding back to normal]

Appdelegate. h

#import "AppDelegate.h"#import "RootViewController.h"@implementation AppDelegate- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions{    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];    // Override point for customization after application launch.    self.window.backgroundColor = [UIColor whiteColor];    [self.window makeKeyAndVisible];        RootViewController *rootCtrl = [[RootViewController alloc] init];        UINavigationController *navCtrl = [[UINavigationController alloc] initWithRootViewController:rootCtrl];        NSMutableArray *mutArrary = [[NSMutableArray alloc] init];        for (int i=0; i<5; i++)    {        NSString *imgName = [NSString stringWithFormat:@"%d.JPG",i];        UIImage *image = [UIImage imageNamed:imgName];        [mutArrary addObject:image];    }        rootCtrl.images = mutArrary;        self.window.rootViewController = navCtrl;        return YES;}@end

Rootviewcontroller. h

@ Interface rootviewcontroller: uiviewcontroller <uiscrollviewdelegate> {nsinteger _ index;} @ property (nonatomic, retain) nsarray * images; // store the displayed Image

Rootviewcontroller. m

# Import "rootviewcontroller. H "# import" photoscrollview. H "@ interface rootviewcontroller () @ end @ implementation rootviewcontroller-(ID) initwithnibname :( nsstring *) bundle :( nsbundle *) handle {self = [Super initwithnibname: nibnameornil Bundle: nibbundleornil]; If (Self) {// custom initialization} return self;}-(void) viewdidload {[Super viewdidload]; // create a rolling view uiscrollview * scrollvi Ew = [[uiscrollview alloc] initwithframe: cgrectmake (0, 0,340,480)]; // hide the horizontal scroll bar scrollview. showshorizontalscrollindicator = no; scrollview. backgroundcolor = [uicolor blackcolor]; scrollview. delegate = self; // sets the page effect scrollview. pagingenabled = yes; // sets the content size to scrollview. contentsize = cgsizemake (340 * _ images. count, 480); [self. view addsubview: scrollview]; for (INT I = 0; I <self. images. count; I ++) {photo Scrollview * photoview = [[photoscrollview alloc] initwithframe: cgrectmake (340 * I, 0,320,480)]; photoview. tag = I + 100; // pass the value to photoview. image = _ images [I]; [scrollview addsubview: photoview] ;}# Pragma mark-uiscrollview delegate-(void) scrollviewdidenddecelerating :( uiscrollview *) scrollview {// 1. get the current page number int currentpage = scrollview. contentoffset. x/340; // 2. restore previous scaling attempts if (currentpage! = _ Index) {// obtain the view int tag = _ index + 100; photoscrollview * view = (photoscrollview *) [scrollview viewwithtag: Tag]; // restore [view setzoomscale: 1];} // 3. record the current page number _ Index = currentpage;}/* # pragma mark-Navigation // In a storyboard-based application, you will often want to do a little preparation before navigation-(void) prepareforsegue :( uistoryboardsegue *) segue sender :( ID) sender {// get the New View Controller Using [segue destinationviewcontroller]. // pass the selected object to the New View Controller .} * // @ end

Photoscrollview. h

@interface PhotoScrollView : UIScrollView<UIScrollViewDelegate>{    UIImageView *_imageView;}@property(nonatomic, retain)UIImage *image;

Photoscrollview. m

# Import "photoscrollview. H "@ implementation photoscrollview-(ID) initwithframe :( cgrect) frame {self = [Super initwithframe: frame]; If (Self) {_ imageview = [[uiimageview alloc] initwithframe: self. bounds]; // data cannot be set here // _ imageview. image = _ image; [self addsubview: _ imageview]; // you can specify the maximum magnification. maximumzoomscale = 2.0; // you can specify the minimum zoomscale. minimumzoomscale =. 5; // hide the scroll bar self. showshorizontalscrollindicator = no; self. showsverticalscrollindicator = no; // sets the proxy self. delegate = self; // Add gesture uitapgesturerecognizer * tap = [[uitapgesturerecognizer alloc] initwithtarget: Self action: @ selector (tapactoin :)]; tap. numberoftapsrequired = 2; [self addgesturerecognizer: tap];} return self;} // gesture RESPONSE event-(void) tapactoin :( uitapgesturerecognizer *) tap {If (self. zoomscale> 1) {// zoom out [self setzoomscale: 1 animated: Yes];} else {// zoom in [self setzoomscale: 2 animated: Yes];}-(void) setimage :( uiimage *) image {_ image = image; _ imageview. image = _ image ;}# Pragma mark-uiscrollview delegate-(uiview *) viewforzoominginscrollview :( uiscrollview *) scrollview {return _ imageview;} @ end

Simple image browser [zoomed images, sliding back to normal]