Filtering NSTextField – Take 2

Thanks to Jim Correia of Bare Bones Software, I have a slightly different method for filtering NSTextFields based on an NSFormatter. While my older method worked, this is a bit cleaner.

Like my old filter, this also has three methods:

- (void) setAcceptableCharacterSet:(NSCharacterSet *) inCharacterSet;
- (void) setMaximumLength:(int) inLength;
- (void) setMaximumValue:(int) inValue;

However, they’re called differently. You’d do something like this:

NSMutableCharacterSet *characterSet = [[NSMutableCharacterSet alloc] init];
[characterSet addCharactersInString:@"0123456789"];
[secondaryTextField setFormatter:[[[PartialFormatter alloc] init] autorelease]];
[[secondaryTextField formatter] setMaximumValue:65535];
[[secondaryTextField formatter] setAcceptableCharacterSet:characterSet];
[characterSet release];

Note that the formatter is based on NSFormatter and not NSNumberFormatter. I actually am using this for a number field as I want the number field to give me back a string instead of a number, so that’s why I put in the setMaximumValue and didn’t base it on NSNumberFormatter.

As always, feedback is welcome.

The attached code can be freely used in commercial and non-commercial projects. While I’d like some credit in the about box, it isn’t necessary. This code has no warranty and you assume all risk for using it.

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