android/app/src/main/java/com/nextcloud/client/core/AsyncRunner.kt

59 lines
2.4 KiB
Kotlin

/*
* Nextcloud - Android Client
*
* SPDX-FileCopyrightText: 2019 Chris Narkiewicz <hello@ezaquarii.com>
* SPDX-License-Identifier: AGPL-3.0-or-later
*/
package com.nextcloud.client.core
typealias OnResultCallback<T> = (result: T) -> Unit
typealias OnErrorCallback = (error: Throwable) -> Unit
typealias OnProgressCallback<P> = (progress: P) -> Unit
typealias IsCancelled = () -> Boolean
typealias TaskFunction<RESULT, PROGRESS> = (
onProgress: OnProgressCallback<PROGRESS>,
isCancelled: IsCancelled
) -> RESULT
/**
* This interface allows to post background tasks that report results via callbacks invoked on main thread.
* It is provided as an alternative for heavy, platform specific and virtually untestable [android.os.AsyncTask]
*
* Please note that as of Android R, [android.os.AsyncTask] is deprecated and [java.util.concurrent] is a recommended
* alternative.
*/
interface AsyncRunner {
/**
* Post a quick background task and return immediately returning task cancellation interface.
*
* Quick task is a short piece of code that does not support interruption nor progress monitoring.
*
* @param task Task function returning result T; error shall be signalled by throwing an exception.
* @param onResult Callback called when task function returns a result.
* @param onError Callback called when task function throws an exception.
* @return Cancellable interface, allowing cancellation of a running task.
*/
fun <RESULT> postQuickTask(
task: () -> RESULT,
onResult: OnResultCallback<RESULT>? = null,
onError: OnErrorCallback? = null
): Cancellable
/**
* Post a background task and return immediately returning task cancellation interface.
*
* @param task Task function returning result T; error shall be signalled by throwing an exception.
* @param onResult Callback called when task function returns a result,
* @param onError Callback called when task function throws an exception.
* @param onProgress Callback called when task function reports progress update.
* @return Cancellable interface, allowing cancellation of a running task.
*/
fun <RESULT, PROGRESS> postTask(
task: TaskFunction<RESULT, PROGRESS>,
onResult: OnResultCallback<RESULT>? = null,
onError: OnErrorCallback? = null,
onProgress: OnProgressCallback<PROGRESS>? = null
): Cancellable
}