Unable to tell a child widget to be 100% the height of the parent widget

Given this code:

from textual.app import App, ComposeResult
from textual.containers import Horizontal
from textual.widgets import Static

class HeightApp( App[ None ] ):

    CSS = """
    Horizontal {
        border: solid red;
        height: auto;
    }

    Static {
        border: solid green;
        width: auto;
    }

    #fill_parent {
        height: auto;
    }

    #static {
        height: 23;
    }
    """

    def compose( self ) -> ComposeResult:
        yield Horizontal(
            Static( "How to make this as tall as container?", id="fill_parent" ),
            Static( "This has default\nheight\nbut a\nfew lines" ),
            Static( "I have a static height", id="static" ),
        )

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

this is the output: Now imagine you want to make the first widget exactly as tall as the containing widget. Given all other things seen in CSS, it feels like you should be able to set the height of fill_parent to 100% and it will vertically fill the parent – in effect matching the height of the tallest non-relative-sized widget. But if I do that the widget does this instead: It’s as if it is taking the height from the container’s container, or simply the Screen.

Note the same happens if height is set to 1fr.

Raising this issue to first check if this is the expected behaviour.

[willmcgugan]

Should be fixed in main. Making that column expand is now as simple as:

height: 100%;

[davep]

If I’m understanding you correctly… that’s fine, the enclosing Horizontal avoids those:

I’ve not dived into the code yet (this issue is for future investigation for me as much as anything), but I feel like there could be a tweak to be had here regarding deciding which child height wins when trying to decide the best height.