移除 UIColor CGColor - KVC 警告

Question

How to remove [[UIColor grayColor] CGColor] stupid warning?

[self setValue:
     [[UIColor grayColor] CGColor] 
          forKeyPath:[NSString stringWithFormat:@"_View_%@%d.layer.borderColor", 
              i>=10?@"":@"0", i]];

Incompatible pointer types sending 'CGColorRef' (aka 'struct CGColor *') to parameter of type 'id'

thanks.

Answer 1

cast CGColor to id type:

[self setValue:
     (id)[[UIColor grayColor] CGColor] 
          forKeyPath:[NSString stringWithFormat:@"_View_%@%d.layer.borderColor", 
              i>=10?@"":@"0", i]];

Answer 2

This will perform same as above code.

[self setValue:
 (id)[[UIColor grayColor] CGColor] 
      forKeyPath:[NSString stringWithFormat:@"_View_%02d.layer.borderColor", i]];