ExtendedTask
Supervise an extended, long-running task
reactive.ExtendedTask
reactive.ExtendedTask(self, func)Attributes
| Name | Description |
|---|---|
| error | Reactive value that tracks the error raised by the task, if the current status is “error”. If the status is not “error”, the value will be unset, and a silent exception will be raised if you try to read it. Calling code should generally not read this value directly, but instead use the result() method, which is designed to behave correctly regardless of the current status. |
| status | Reactive value that tracks the current status of the task. The value will be one of “initial”, “running”, “success”, “error”, or “cancelled”. |
| value | Reactive value that tracks the result of the task, if the current status is “success”. If the status is not “success”, the value will be unset, and a silent exception will be raised if you try to read it. Calling code should generally not read this value directly, but instead use the result() method, which is designed to behave correctly regardless of the current status. |
Methods
| Name | Description |
|---|---|
| cancel | Cancel the current invocation, if any. If there are pending invocations, cancel those too. |
| invoke | Request execution of the slow computation. If there’s already a computation in progress, this will queue up the new invocation to be run after the current one. The arguments to this function are passed to the underlying function. |
| result | Call from a reactive context (e.g. a render function, calc, or effect) to get the result of the computation. |
cancel
reactive.ExtendedTask.cancel()Cancel the current invocation, if any. If there are pending invocations, cancel those too.
invoke
reactive.ExtendedTask.invoke(*args, **kwargs)Request execution of the slow computation. If there's already a computation in progress, this will queue up the new invocation to be run after the current one. The arguments to this function are passed to the underlying function.
Returns
: None-
Immediately returns
None. The results of the computation will be available via theresult()method.
result
reactive.ExtendedTask.result()Call from a reactive context (e.g. a render function, calc, or effect) to get the result of the computation.
If the computation has finished successfully, the result will be returned.
If the computation has finished with an error, the error will be raised.
If the computation has never run, or the most recent run was cancelled, a silent exception will be raised that will clear any downstream outputs.
If the computation is currently running, a special type of silent exception will be raised that will cause the output to visually reflect that calculation is in progress.
reactive.ExtendedTask.invoke
reactive.ExtendedTask.invoke(*args, **kwargs)Request execution of the slow computation. If there's already a computation in progress, this will queue up the new invocation to be run after the current one. The arguments to this function are passed to the underlying function.
Returns
: None-
Immediately returns
None. The results of the computation will be available via theresult()method.
reactive.ExtendedTask.result
reactive.ExtendedTask.result()Call from a reactive context (e.g. a render function, calc, or effect) to get the result of the computation.
If the computation has finished successfully, the result will be returned.
If the computation has finished with an error, the error will be raised.
If the computation has never run, or the most recent run was cancelled, a silent exception will be raised that will clear any downstream outputs.
If the computation is currently running, a special type of silent exception will be raised that will cause the output to visually reflect that calculation is in progress.
reactive.ExtendedTask.cancel
reactive.ExtendedTask.cancel()Cancel the current invocation, if any. If there are pending invocations, cancel those too.