MaskedInput¶

A masked input derived from Input, allowing to restrict user input and give visual aid via a simple template mask, which also acts as an implicit validator.

• Focusable
• Container

Example¶

The example below shows a masked input to ease entering a credit card number.

from textual.app import App, ComposeResult
from textual.widgets import Label, MaskedInput


class MaskedInputApp(App):
    # (1)!
    CSS = """
    MaskedInput.-valid {
        border: tall $success 60%;
    }
    MaskedInput.-valid:focus {
        border: tall $success;
    }
    MaskedInput {
        margin: 1 1;
    }
    Label {
        margin: 1 2;
    }
    """

    def compose(self) -> ComposeResult:
        yield Label("Enter a valid credit card number.")
        yield MaskedInput(
            template="9999-9999-9999-9999;0",  # (2)!
        )


app = MaskedInputApp()

if __name__ == "__main__":
    app.run()

Reactive Attributes¶

The template string format¶

A MaskedInput template length defines the maximum length of the input value. Each character of the mask defines a regular expression used to restrict what the user can insert in the corresponding position, and whether the presence of the character in the user input is required for the MaskedInput value to be considered valid, according to the following table:

There are some special characters that can be used to control automatic case conversion during user input: > converts all subsequent user input to uppercase; < to lowercase; ! disables automatic case conversion. Any other character that appears in the template mask is assumed to be a separator, which is a character that is automatically inserted when user reaches its position. All mask characters can be escaped by placing \ in front of them, allowing any character to be used as separator. The mask can be terminated by ;c, where c is any character you want to be used as placeholder character. The placeholder parameter inherited by Input can be used to override this allowing finer grain tuning of the placeholder string.

Messages¶

• MaskedInput.Changed
• MaskedInput.Submitted

Bindings¶

The masked input widget defines the following bindings:

Component Classes¶

The masked input widget provides the following component classes:

template = template

action_cursor_left()

action_cursor_left_word()

action_cursor_right()

action_cursor_right_word()

action_delete_left()

action_delete_left_all()

action_delete_left_word()

action_delete_right()

action_delete_right_word()

action_home()

clear()

insert_text_at_cursor(text)

validate(value)

validate_value(value)