- (void)viewDidLoad {

    [super viewDidLoad];

    UIButton * btn = [UIButton buttonWithType:UIButtonTypeContactAdd];

    btn.frame =CGRectMake(30, 30, 30, 30);

    [self.view addSubview:btn];

    [btn addTarget:self action:@selector(btnClick:) forControlEvents:UIControlEventTouchUpInside];

}

-(void)btnClick:(UIButton *)sender

{

    [self savePhoto];

}

// 保存图片到相册功能，ALAssetsLibraryiOS9.0 以后用photoliabary 替代，

-(void)savePhoto

{

    UIImage * image = [self captureImageFromView:self.view];

    ALAssetsLibrary * library = [ALAssetsLibrary new];

    NSData * data = UIImageJPEGRepresentation(image, 1.0);

    [library writeImageDataToSavedPhotosAlbum:data metadata:nil completionBlock:nil];

}

//截图功能

-(UIImage *)captureImageFromView:(UIView *)view

{

    CGRect screenRect = [view bounds];

    UIGraphicsBeginImageContext(screenRect.size);

    CGContextRef ctx = UIGraphicsGetCurrentContext();

    [view.layer renderInContext:ctx];

    UIImage * image = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    return image;

}