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Reactive

The Reactive class implements reactivity.

Reactive class

def __init__(
    self,
    default,
    *,
    layout=False,
    repaint=True,
    init=False,
    always_update=False,
    compute=True
):

Bases: Generic[ReactiveType]

Reactive descriptor.

Parameters
Parameter Default Description
default
ReactiveType | Callable[[], ReactiveType]
required

A default value or callable that returns a default.

layout
bool
False

Perform a layout on change.

repaint
bool
True

Perform a repaint on change.

init
bool
False

Call watchers on initialize (post mount).

always_update
bool
False

Call watchers even when the new value equals the old value.

compute
bool
True

Run compute methods when attribute is changed.

TooManyComputesError class

Bases: Exception

Raised when an attribute has public and private compute methods.

reactive class

def __init__(
    self,
    default,
    *,
    layout=False,
    repaint=True,
    init=True,
    always_update=False
):

Bases: Reactive[ReactiveType]

Create a reactive attribute.

Parameters
Parameter Default Description
default
ReactiveType | Callable[[], ReactiveType]
required

A default value or callable that returns a default.

layout
bool
False

Perform a layout on change.

repaint
bool
True

Perform a repaint on change.

init
bool
True

Call watchers on initialize (post mount).

always_update
bool
False

Call watchers even when the new value equals the old value.

var class

def __init__(self, default, init=True, always_update=False):

Bases: Reactive[ReactiveType]

Create a reactive attribute (with no auto-refresh).

Parameters
Parameter Default Description
default
ReactiveType | Callable[[], ReactiveType]
required

A default value or callable that returns a default.

init
bool
True

Call watchers on initialize (post mount).

always_update
bool
False

Call watchers even when the new value equals the old value.