Allow only alphabetic characters
Allow only digits
Edited field expects email address
Allow any character
Edited field expects the name of a person
Edited field expects numbers
Like %GTK_INPUT_PURPOSE_FREE_FORM, but characters are hidden
Edited field expects phone number
Like %GTK_INPUT_PURPOSE_DIGITS, but characters are hidden
Allow any character, in addition to control codes
Edited field expects URL
Describes primary purpose of the input widget.
This information is useful for on-screen keyboards and similar input methods to decide which keys should be presented to the user.
Note that the purpose is not meant to impose a totally strict rule about allowed characters, and does not replace input validation. It is fine for an on-screen keyboard to let the user override the character set restriction that is expressed by the purpose. The application is expected to validate the entry contents, even if it specified a purpose.
The difference between %GTK_INPUT_PURPOSE_DIGITS and %GTK_INPUT_PURPOSE_NUMBER is that the former accepts only digits while the latter also some punctuation (like commas or points, plus, minus) and “e” or “E” as in 3.14E+000.
This enumeration may be extended in the future; input methods should interpret unknown values as “free form”.