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#import "ViewController.h"
 
@interface ViewController ()
 
 
@end
 
@implementation ViewController
 
- (void)viewDidLoad {
    [super viewDidLoad];
    [self beginGeneratingDeviceOrientationNotifications];
}
 
- (void)background {
    UIImage *imageA = [UIImage imageNamed:@"123.png"];
    CGSize imageSize = imageA.size;
    CGFloat newWidth = (([[ UIScreen mainScreen ] bounds].size.height) / imageSize.height) * imageSize.width;
    
    UIGraphicsBeginImageContext(self.view.frame.size);
    [imageA drawInRect:CGRectMake(0, 0, newWidth, [[ UIScreen mainScreen ] bounds].size.height)];
    UIImage *resizedImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    
    self.view.backgroundColor = [UIColor colorWithPatternImage:resizedImage];
}
 
- (void)beginGeneratingDeviceOrientationNotifications{
    NSLog(@"it started");
    [[NSNotificationCenter defaultCenter]
     addObserver:self
     selector:@selector(deviceOrientationDidChangeNotification:)
     name:UIDeviceOrientationDidChangeNotification
     object:nil];
}
 
- (void)deviceOrientationDidChangeNotification:(NSNotification*)note {
    [self background];
    NSLog(@"it changed");
}
 
 
- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
}
 
//- (UIImage *)imageWithImage:(UIImage *)image convertToSize:(CGSize)size {
//    UIGraphicsBeginImageContext(size);
//    [image drawInRect:CGRectMake(0, 0, size.width, size.height)];
//    UIImage *destImage = UIGraphicsGetImageFromCurrentImageContext();
//    UIGraphicsEndImageContext();
//    return destImage;
//}
 
 
@end