[Question] How does the expand=True (or int) even work?

[angrymidget4728]

Question

I was initially under the impression that the expand property is a jacked-up/combined version of certain css properties, and while that is true to some extent, it doesn't seem flexible (assuming I'm using it correctly).

The following code gives what I wanted.

    content1 = ft.Container(
        expand=1, 
        bgcolor=ft.colors.GREY_900, 
        margin=ft.margin.only(20,0,20,20), 
        border_radius=8,
        # content=ft.Text('item', expand=1,)
    )
    
    page.add(tabs)
    page.add(content1)

But as soon as add content, it shrinks the column to fit the content.

    content1 = ft.Container(
        expand=1, 
        bgcolor=ft.colors.GREY_900, 
        margin=ft.margin.only(20,0,20,20), 
        border_radius=8,
        content=ft.Text('item', expand=1,)
    )
    
    page.add(tabs)
    page.add(content1)

I recognize that this is the same behavior that occurs for Row() (since the tabs are in a row) but in such a case it is causing more problems than fix. My immediate thought was to use page.width but I realized that wouldn't be the same as the css vh measurement that constantly updates according to window size. Is using page.width/page.on_window_event with page.update() my only way or is there a more elegant/built-in way to tackle this using just the expand property?

EDIT:
As an analogy, practically any element in Figma has three options for both height and width each: fixed width, fill container, hug contents. From my test of Flet, the expand=True seems to apply 'fill container' for both height and width of a control when there is no content present. If you add content, then it takes its own liberty to make height=fill container, but width=hug contents (if in a column, and vice versa for row).
How do I take control of this behavior with Flet similar to Figma?

Code sample

No response

Error message

No response

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• I have searched for answers to my question both in the issues and in previous discussions.

[EmberLightVFX]

I don't know why but if I added alignment=ft.alignment.top_left, to content1 it works as I would expect

    content1 = ft.Container(
        expand=1, 
        alignment=ft.alignment.top_left,
        bgcolor=ft.colors.GREY_900, 
        margin=ft.margin.only(20,0,20,20), 
        border_radius=8,
        content=ft.Text('item', expand=1,)
    )
    
    page.add(content1)