Variable number formatter in text field

I want to insert a number into a Text Field.

If the is larger then 0.001 the number should be displayed as 1.234 (0.000). If the is smaller then 0.001 the number should be displayed as 1.234E-5 (0.000E+0).

I had a look in "LOCALE DATA MARKUP LANGUAGE (LDML)" using Choice Pat开发者_开发技巧terns but this seems not to work from Interface Builder.

How can I do this?

NSNumberFormatter doesn't work for you?

Try this on "changes ended" or whatever it is on the Mac.

- (IBAction) checkFloat: (id)sender
{
    double test = [sender doubleValue];
    if (test > 0.001)
        [sender setStringValue:[NSString stringWithFormat:@"%E",test];

    // etc.

}

Look up string formats here.