How to set alpha of uiclearcolor?

Question

I am currently doing this:

UIColor *myColor = [UIColor clearColor]; 

This is great but i would like to specify a certain alpha of "myColor". How would i do so?

Answer 1

If you have an existing color, you can return a new one with a specified alpha, like this:

- (void)setBackgroundColor:(UIColor *)color  {     self.backgroundColor = [color colorWithAlphaComponent:0.3f]; } 

Answer 2

[UIColor clearColor] is, how should I put it?, clear!

It is a convenience class method returning a UIColor with alpha at zero.

If you want a color with a fractional amount of transparency:

+ (UIColor *)colorWithRed:(CGFloat)red green:(CGFloat)green blue:(CGFloat)blue alpha:(CGFloat)alpha 

Or one of the other UIColor class methods.

Answer 3

You can use colorWithWhite:alpha like so:

[UIColor colorWithWhite:1.0 alpha:0.5];

Or if you want a specific color:

[UIColor colorWithRed:1.0 green:1.0 blue:0.3 alpha:0.72];

Check out the docs.

Answer 4

For Swift you can use:

UIColor.black.withAlphaComponent(0.5)

Or RGB Colors:

UIColor(red: 0/255.0 , green: 0/255.0 , blue: 0/255.0 , alpha: 0.5)