Is it possible to create Screen "template"?

[yikaifeng]

I want to create king of template for screens. It has header, footer, other main space is a horizontal container:

• with left sidebar (menu)
• with right vertical container
  The vertical container has:
• container id='page'
• RichLog

So, on every child screen I just want to compose only inside container id=page. In compose method I write 'yield from super().compose()', but I can't get container with 'self.query_one('#page', Container)', the error is "NoMatches: No nodes match '#page' on My screen()"

[willmcgugan]

You can only query the DOM once it has been mounted, not in the compose method.

How about this?

def compose(self) -> ComposeResult:
    with Vertical(id="page"):
        yield from super().compose()

[yikaifeng]

I meant, I have class MyScreen with those containers. Then I want to create child screens classes like ChildScreen(MyScreen) with the same structure/design except Container(id='page'). And I want to compose only the container content. Menu and log anyways the same

[willmcgugan]

That's how you would do it. Use yield from with your custom content.

In the base class:

def compose(self) -> ComposeResult:
    yield Footer()
    yield Panel()
    with Container(id='page'):
        yield from self.custom()

def custom(self) -> ComposeResult:
    yield Static("Hello, World")

In the super class, define custom:

def custom(self) -> ComposeResult:
    yield Static("My customized content")

[yikaifeng]

Thank you very much