(Coroutine)管理类——TaskManager工具分享
By D.S.Qiu
尊重他人的劳动，支持原创，转载请注明出处：http.dsqiu.iteye.com
在分享 vp_Timer 中提到，没有继承的MonoBehaviour，没有Update，InVoke 和StartCoroutine的机制，vp_Timer就是提供了InVoke的机制，而且还可以统一管理。本篇D.S.Qiu要分享的TaskManager就是一个协程 管理类。 TaskManager —— Unity3D Managed Coroutines with Start, Stop, Resume ，看着就觉得很强大，当然是对于我这种对协程理解不深的来说。下面贴出 The Motivation of the author：
/// The motivation for this is twofold:
///
/// 1. The existing coroutine API provides no means of stopping specific
/// coroutines; StopCoroutine only takes a string argument, and it stops
/// all coroutines started with that same string; there is no way to stop
/// coroutines which were started directly from an enumerator. This is
/// not robust enough and is also probably pretty inefficient.
///
/// 2. StartCoroutine and friends are MonoBehaviour methods. This means
/// that in order to start a coroutine, a user typically must have some
/// component reference handy. There are legitimate cases where such a
/// constraint is inconvenient. This implementation hides that
/// constraint from the user.
代码很简单，但却很解渴，Unity官方只听过了StopCoroutine(string methodName)或StopAllCoroutine() 这两个停止方法，从api就会觉得Unity的整体方法论还不完善，所以才会觉得TaskManager的难能可贵。由于源码简单，就不做解释了，See source for document ：
/// Simple, really. There is no need to initialize or even refer to TaskManager.
/// When the first Task is created in an application, a "TaskManager" GameObject
/// will automatically be added to the scene root with the TaskManager component
/// attached. This component will be responsible for dispatching all coroutines
/// behind the scenes.
///
/// Task also provides an event that is triggered when the coroutine exits.
using UnityEngine;
using System.Collections;
/// A Task object represents a coroutine. Tasks can be started, paused, and stopped.
/// It is an error to attempt to start a task that has been stopped or which has
/// naturally terminated.
public class Task
{
/// Returns true if and only if the coroutine is running. Paused tasks
/// are considered to be running.
public bool Running {
get {
return task.Running;
}
}
/// Returns true if and only if the coroutine is currently paused.
public bool Paused {
get {
return task.Paused;
}
}
/// Delegate for termination subscribers. manual is true if and only if
/// the coroutine was stopped with an explicit call to Stop().
public delegate void FinishedHandler(bool manual);
/// Termination event. Triggered when the coroutine completes execution.
public event FinishedHandler Finished;
/// Creates a new Task object for the given coroutine.
///
/// If autoStart is true (default) the task is automatically started
/// upon construction.
public Task(IEnumerator c, bool autoStart = true)
{
task = TaskManager.CreateTask(c);
task.Finished += TaskFinished;
if(autoStart)
Start();
}
/// Begins execution of the coroutine
public void Start()
{
task.Start();
}
/// Discontinues execution of the coroutine at its next yield.
public void Stop()
{
task.Stop();
}
public void Pause()
{
task.Pause();
}
public void Unpause()
{
task.Unpause();
}
void TaskFinished(bool manual)
{
FinishedHandler handler = Finished;
if(handler != null)
handler(manual);
}
TaskManager.TaskState task;
}
class TaskManager : MonoBehaviour
{
public class TaskState
{
public bool Running {
get {
return running;
}
}
public bool Paused {
get {
return paused;
}
}
public delegate void FinishedHandler(bool manual);
public event FinishedHandler Finished;
IEnumerator coroutine;
bool running;
bool paused;
bool stopped;
public TaskState(IEnumerator c)
{
coroutine = c;
}
public void Pause()
{
paused = true;
}
public void Unpause()
{
paused = false;
}
public void Start()
{
running = true;
singleton.StartCoroutine(CallWrapper());
}
public void Stop()
{
stopped = true;
running = false;
}
IEnumerator CallWrapper()
{
yield return null;
IEnumerator e = coroutine;
while(running) {
if(paused)
yield return null;
else {
if(e != null && e.MoveNext()) {
yield return e.Current;
}
else {
running = false;
}
}
}
FinishedHandler handler = Finished;
if(handler != null)
handler(stopped);
}
}
static TaskManager singleton;
public static TaskState CreateTask(IEnumerator coroutine)
{
if(singleton == null) {
GameObject go = new GameObject("TaskManager");
singleton = go.AddComponent();
}
return new TaskState(coroutine);
}
}
Usage Example:
/// Example usage:
///
/// ----------------------------------------------------------------------------
/// IEnumerator MyAwesomeTask()
/// {
/// while(true) {
/// Debug.Log("Logcat iz in ur consolez, spammin u wif messagez.");
/// yield return null;
//// }
/// }
///
/// IEnumerator TaskKiller(float delay, Task t)
/// {
/// yield return new WaitForSeconds(delay);
/// t.Stop();
/// }
///
/// void SomeCodeThatCouldBeAnywhereInTheUniverse()
/// {
/// Task spam = new Task(MyAwesomeTask());
/// new Task(TaskKiller(5, spam));
/// }
/// ----------------------------------------------------------------------------
小结：
本文主要是分享我的收藏的一些“干货”，TaskManager 和 vp_Timer 在项目中发挥了很大的作用，D.S.Qiu 一再觉得强大的东西不都是复杂的，能够使用最简单的本质方法解决问题才是代码设计的追求。 文末附上了相关的链接以及TaskManager的代码。
如果您对D.S.Qiu有任何建议或意见可以在文章后面评论，或者发邮件（[email protected])交流，您的鼓励和支持是我前进的动力，希望能有更多更好的分享。
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参考：
①Unity-TaskManager：https://github.com/krockot/Unity-TaskManager
②Programmer Instincts：http://programmerinstincts.com/214/