android.os.AsyncTask#getStatus ( )源码实例Demo

/**
 * 如果任务未执行完毕，则取消任务
 *
 * @param clazz Activity Class
 */
public void unregisterAsyncTask(Class<? extends BaseActivity> clazz) {
    ArrayList<AsyncTask> tasks = new ArrayList<>(mTasks.removeAll(clazz));
    int size = tasks.size();
    if (size > 0) {
        for (int i = 0; i < size; i++) {
            AsyncTask task = tasks.get(i);
            //you may call the cancel() method but if it is not handled in doInBackground() method
            if (task != null && task.getStatus() != AsyncTask.Status.FINISHED) {
                task.cancel(true);
            }
        }
    }
}
 

/**
 * Try to execute the supplied async task.
 *
 * @param asyncTask The async task to be executed.
 *
 * @see AsyncTask#execute(Object[])
 */
@SuppressWarnings("unchecked")
public static void executeTask(@Nullable AsyncTask asyncTask) {
    try {
        if (asyncTask != null && asyncTask.getStatus() != AsyncTask.Status.RUNNING) {
            asyncTask.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, (Object[]) null);
        }
    } catch (Exception ignored) {
    }
}
 

/**
 * Try to cancel the supplied async task.
 *
 * @param asyncTask The async task to be cancelled.
 *
 * @see AsyncTask#cancel(boolean)
 */
public static void cancelTask(@Nullable AsyncTask asyncTask) {
    try {
        if (asyncTask != null && asyncTask.getStatus() == AsyncTask.Status.RUNNING) {
            asyncTask.cancel(true);
        }
    } catch (Exception ignored) {
    }
}
 

public boolean addTask(String key, AsyncTask<?, ?, ?> task) {
	synchronized (lock) {
		if (runningTasks.containsKey(key)) {
			AsyncTask<?, ?, ?> tempTask = runningTasks.get(key);
			if (tempTask != null && tempTask.getStatus() != Status.FINISHED)
				return false;
		}
		runningTasks.put(key, task);
		return true;
	}
}
 

/**
 * Cancel an {@link AsyncTask}.
 *
 * @param mayInterruptIfRunning <tt>true</tt> if the thread executing this
 *        task should be interrupted; otherwise, in-progress tasks are allowed
 *        to complete.
 */
public static void cancelTask(AsyncTask<?, ?, ?> task, boolean mayInterruptIfRunning) {
    if (task != null && task.getStatus() != AsyncTask.Status.FINISHED) {
        task.cancel(mayInterruptIfRunning);
    }
}