Question

I have two TextFields. One accepts only numerical values and the other hex values. I am using NSNumberformatter to set the numerical-only input, like:

NSNumberFormatter *formatter;
formatter = [[[NSNumberFormatter alloc] init] autorelease];
[formatter setNumberStyle:NSNumberFormatterNoStyle];

And then apply it to the TextField.

How do I do the same but only accepting Hex values? By hex I mean 1234567890ABCDEF.

Alternatively, if it cannot be done, how do I check that the text on that TextField is hex?

Thanks

Answer 1

See this answer for a much better explanation, but it would be something like:

- (void)controlTextDidChange:(NSNotification *)aNotification {
    NSError *outError;
    NSControl *textField = [aNotification object];
    NSString *myText = [textField stringValue];

    // check if myText is 0-9 or a-f, do something with it if its not hex.

    // update the NSNextField with the validated text
    [postingObject setStringValue:myText];
}