Max-height

The max-height style sets a maximum height for a widget.

Syntax

max-height: <scalar>;

The max-height style accepts a <scalar> that defines an upper bound for the height of a widget. That is, the height of a widget is never allowed to exceed max-height.

Example

The example below shows some placeholders that were defined to span vertically from the top edge of the terminal to the bottom edge. Then, we set max-height individually on each placeholder.

Outputmax_height.pymax_height.tcss

from textual.app import App
from textual.containers import Horizontal
from textual.widgets import Placeholder


class MaxHeightApp(App):
    CSS_PATH = "max_height.tcss"

    def compose(self):
        yield Horizontal(
            Placeholder("max-height: 10w", id="p1"),
            Placeholder("max-height: 999", id="p2"),
            Placeholder("max-height: 50%", id="p3"),
            Placeholder("max-height: 10", id="p4"),
        )


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

Horizontal {
    height: 100%;
    width: 100%;
}

Placeholder {
    height: 100%;
    width: 1fr;
}

#p1 {
    max-height: 10w;
}

#p2 {
    max-height: 999;  /* (1)! */
}

#p3 {
    max-height: 50%;
}

#p4 {
    max-height: 10;
}

1. This won't affect the placeholder because its height is less than the maximum height.

CSS

/* Set the maximum height to 10 rows */
max-height: 10;

/* Set the maximum height to 25% of the viewport height */
max-height: 25vh;

Python

# Set the maximum height to 10 rows
widget.styles.max_height = 10

# Set the maximum height to 25% of the viewport height
widget.styles.max_height = "25vh"

See also

• min-height to set a lower bound on the height of a widget.
• height to set the height of a widget.