iOS Gradient with noise overlaid (like https://www.dropbox.com/s/6a6lsqasee0zp1q/bgview.png?dl=0)

gistfile1.m

// Just a quick hack to achieve something like this: https://www.dropbox.com/s/6a6lsqasee0zp1q/bgview.png?dl=0
@interface MMGradientBackgroundView()

@property (strong, nonatomic) UIImage *noiseImage;

@end

@implementation MMGradientBackgroundView

- (instancetype)initWithFrame:(CGRect)frame {
    if (self = [super initWithFrame:frame]) {
        [self commonInit];
    }

    return self;
}

- (instancetype)init {
    if (self = [super init]) {
        [self commonInit];
    }

    return self;
}

- (void)commonInit {
    self.noiseImage = [UIImage imageNamed:@"[email protected]"]; // https://www.dropbox.com/s/t9ky8226eybqfia/noisemap%402x.png?dl=0
}


- (void)drawRect:(CGRect)rect {
    [super drawRect:rect];

    CGContextRef context = UIGraphicsGetCurrentContext();
    CGColorRef startColor = [UIColor colorWithWhite:.46f alpha:1.0f].CGColor;
    CGColorRef endColor = [UIColor colorWithWhite:0.f alpha:0.f].CGColor;
    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
    CGFloat locations[] = { 0.0f, 1.0f };

    NSArray *colors = @[(__bridge id)startColor, (__bridge id)endColor];

    CGGradientRef gradient = CGGradientCreateWithColors(colorSpace, (__bridge CFArrayRef)colors, locations);

    CGPoint startPoint = CGPointMake(CGRectGetMidX(rect), CGRectGetMinY(rect));
    CGPoint endPoint = CGPointMake(CGRectGetMidX(rect), CGRectGetMaxY(rect));

    CGContextSaveGState(context);
    CGContextAddRect(context, rect);
    CGContextClip(context);

    CGContextDrawLinearGradient(context, gradient, startPoint, endPoint, 0);
    CGContextRestoreGState(context);

    CGGradientRelease(gradient);
    CGColorSpaceRelease(colorSpace);

    CGContextDrawTiledImage(context, CGRectMake(0, 0, self.noiseImage.size.width, self.noiseImage.size.height), self.noiseImage.CGImage);
}

@end