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Version: 0.3.1

01: Hello World

The smallest possible Weaverlet app. A single WeaverletComponent subclass with a layout-only get_layout method, handed to WeaverletApp. No callbacks, no IDs, no composition. Just to confirm the install works and to see the shape of a component.

The script​

from weaverlet.base import WeaverletComponent, WeaverletApp
from dash import html

class HelloWorldComponent(WeaverletComponent):

    def __init__(self, **kwargs):
        super().__init__(**kwargs)

    def get_layout(self):
        return html.Div(f'hello world!')

helloworld_component = HelloWorldComponent()
wapp = WeaverletApp(root_component=helloworld_component)
wapp.app.run(port=8086)

Expected output​

Running the app opens http://localhost:8086 showing a blank white page with the text "hello world!".

Notes​

  • Every Weaverlet app needs at least one WeaverletComponent subclass with get_layout implemented and a single WeaverletApp(root_component=...) call.
  • wapp.app.run(...) is the modern Dash 4 entry point. never app.run_server(...), which was removed in Dash 4.
  • The script uses the legacy import from weaverlet.base import .... The modern equivalent is from weaverlet import WeaverletComponent, WeaverletApp: both work in 0.3+.

Try it locally​

pip install weaverlet
# Save the script above as helloworld.py
python helloworld.py

See also​