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Lazy

marimo.lazy

lazy(
    element: Union[
        Callable[[], object],
        object,
        Callable[[], Coroutine[None, None, object]],
    ],
    show_loading_indicator: bool = False,
)

Bases: UIElement[bool, bool]

Lazy load a component until it is visible.

Use mo.lazy to defer rendering of an item until it's visible. This is useful for loading expensive components only when they are needed, e.g., only when an accordion or tab is opened.

The argument to mo.lazy can be an object to render lazily, or a function that returns the object to render (that is, functions are lazily evaluated). The function can be synchronous or asynchronous. Using a function is useful when the item to render is the result of a database query or some other expensive operation.

Examples:

Create a lazy-loaded tab:

tabs = mo.ui.tabs(
    {"Overview": tab1, "Charts": mo.lazy(expensive_component)}
)

Create a lazy-loaded accordion:

accordion = mo.ui.accordion({"Charts": mo.lazy(expensive_component)})

Usage with async functions:

async def expensive_component(): ...


mo.lazy(expensive_component)

PARAMETER DESCRIPTION
element

Object or callable that returns content to be lazily loaded.

TYPE: Union[Callable[[], object], object, Callable[[], Coroutine[None, None, object]]]

show_loading_indicator

Whether to show a loading indicator while the content is being loaded. Defaults to False.

TYPE: bool DEFAULT: False

text property

text: str

A string of HTML representing this element.

value property writable

value: T

The element's current value.

batch

batch(**elements: UIElement[JSONType, object]) -> batch

Convert an HTML object with templated text into a UI element.

This method lets you create custom UI elements that are represented by arbitrary HTML.

Example
user_info = mo.md(
    '''
    - What's your name?: {name}
    - When were you born?: {birthday}
    '''
).batch(name=mo.ui.text(), birthday=mo.ui.date())

In this example, user_info is a UI Element whose output is markdown and whose value is a dict with keys 'name' and 'birthday' (and values equal to the values of their corresponding elements).

PARAMETER DESCRIPTION
elements

the UI elements to interpolate into the HTML template.

TYPE: UIElement[JSONType, object] DEFAULT: {}

callout

callout(
    kind: Literal[
        "neutral", "danger", "warn", "success", "info"
    ] = "neutral"
) -> Html

Create a callout containing this HTML element.

A callout wraps your HTML element in a raised box, emphasizing its importance. You can style the callout for different situations with the kind argument.

Examples:

mo.md("Hooray, you did it!").callout(kind="success")
mo.md("It's dangerous to go alone!").callout(kind="warn")

center

center() -> Html

Center an item.

Example
mo.md("# Hello, world").center()
RETURNS DESCRIPTION
Html

An Html object.

form

form(
    label: str = "",
    *,
    bordered: bool = True,
    loading: bool = False,
    submit_button_label: str = "Submit",
    submit_button_tooltip: Optional[str] = None,
    submit_button_disabled: bool = False,
    clear_on_submit: bool = False,
    show_clear_button: bool = False,
    clear_button_label: str = "Clear",
    clear_button_tooltip: Optional[str] = None,
    validate: Optional[
        Callable[[Optional[JSONType]], Optional[str]]
    ] = None,
    on_change: Optional[
        Callable[[Optional[T]], None]
    ] = None
) -> form[S, T]

Create a submittable form out of this UIElement.

Creates a form that gates submission of a UIElement's value until a submit button is clicked. The form's value is the value of the underlying element from the last submission.

Examples:

Convert any UIElement into a form:

prompt = mo.ui.text_area().form()

Combine with HTML.batch to create a form made out of multiple UIElements:

form = (
    mo.ui.md(
        '''
    **Enter your prompt.**

    {prompt}

    **Choose a random seed.**

    {seed}
    '''
    )
    .batch(
        prompt=mo.ui.text_area(),
        seed=mo.ui.number(),
    )
    .form()
)

PARAMETER DESCRIPTION
label

A text label for the form.

TYPE: str DEFAULT: ''

bordered

Whether the form should have a border.

TYPE: bool DEFAULT: True

loading

Whether the form should be in a loading state.

TYPE: bool DEFAULT: False

submit_button_label

The label of the submit button.

TYPE: str DEFAULT: 'Submit'

submit_button_tooltip

The tooltip of the submit button.

TYPE: Optional[str] DEFAULT: None

submit_button_disabled

Whether the submit button should be disabled.

TYPE: bool DEFAULT: False

clear_on_submit

Whether the form should clear its contents after submitting.

TYPE: bool DEFAULT: False

show_clear_button

Whether the form should show a clear button.

TYPE: bool DEFAULT: False

clear_button_label

The label of the clear button.

TYPE: str DEFAULT: 'Clear'

clear_button_tooltip

The tooltip of the clear button.

TYPE: Optional[str] DEFAULT: None

validate

A function that takes the form's value and returns an error message if invalid, or None if valid.

TYPE: Optional[Callable[[Optional[JSONType]], Optional[str]]] DEFAULT: None

on_change

A callback that takes the form's value and returns an error message if invalid, or None if valid.

TYPE: Optional[Callable[[Optional[T]], None]] DEFAULT: None

left

left() -> Html

Left-justify.

Example
mo.md("# Hello, world").left()
RETURNS DESCRIPTION
Html

An Html object.

right

right() -> Html

Right-justify.

Example
mo.md("# Hello, world").right()
RETURNS DESCRIPTION
Html

An Html object.

send_message

send_message(
    message: Dict[str, object],
    buffers: Optional[Sequence[bytes]],
) -> None

Send a message to the element rendered on the frontend from the backend.

style

style(
    style: Optional[dict[str, Any]] = None, **kwargs: Any
) -> Html

Wrap an object in a styled container.

Example
mo.md("...").style({"max-height": "300px", "overflow": "auto"})
mo.md("...").style(max_height="300px", overflow="auto")
PARAMETER DESCRIPTION
style

an optional dict of CSS styles, keyed by property name

TYPE: Optional[dict[str, Any]] DEFAULT: None

**kwargs

CSS styles as keyword arguments

TYPE: Any DEFAULT: {}