adding black overlay with 0.3 opacity over UIImageView

Question

I have a UIImageView and I wanted to add a black overlay on top of it. What is the best way of doing this without having to override drawRect? I was thinking of adding a CALayer

Answer 1

The MDT answer is correct. This is just another way to use a CAGradientLayer beside of UIView . I think it will make what you want with more graphical options.

first you should add

#import 

to your ViewController.m and any place that you want to add this overlay to your UIImage use:

CAGradientLayer *gradientLayer = [CAGradientLayer layer];
gradientLayer.frame = myImageView.layer.bounds;

gradientLayer.colors = [NSArray arrayWithObjects:
                        (id)[UIColor colorWithWhite:0.9f alpha:0.7f].CGColor,
                        (id)[UIColor colorWithWhite:0.0f alpha:0.3f].CGColor,
                        nil];

gradientLayer.locations = [NSArray arrayWithObjects:
                           [NSNumber numberWithFloat:0.0f],
                           [NSNumber numberWithFloat:0.5f],
                           nil];

//If you want to have a border for this layer also
gradientLayer.borderColor = [UIColor colorWithWhite:1.0f alpha:1.0f].CGColor;
gradientLayer.borderWidth = 1;
[myImageView.layer addSublayer:gradientLayer];

I hope this will help you make it