blocks|key|716427|text|这些都与服务有关。我们都知道，服务在后台继续运行，它们也消耗了一些内存来执行。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|716428|因此，随着越来越多的应用程序在android设备上运行，设备内存不断降低，当设备内存变得非常低时，android系统开始终止进程，从而释放进程占用的内存。|716429|但是您可能正在对服务执行一些重要的任务，这也可能在服务停止时终止。因此，这些概念是告诉android系统，当设备内存稳定时，以及当它准备重新启动服务时，您想要执行什么操作。|716430|最简单的解释就是，|716431|START_STICKY-告诉系统，在服务从低内存恢复后，当有足够的内存可用时，创建服务的新副本。在这里，您将失去以前计算过的结果。|offset|length|style|CODE|716432|START_NOT_STICKY-告诉系统，即使它有足够的内存，也不要麻烦地重新启动服务。|716433|START_REDELIVER_INTENT-告诉系统在崩溃后重新启动服务，并重新传递崩溃时存在的意图。|716434|entityMap^0|0|0|0|0|0|D|0|0|H|0|0|N|0^^$0|@$1|2|3|4|5|6|7|T|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|U|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|V|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|W|8|@]|9|@]|A|$]]|$1|H|3|I|5|6|7|X|8|@$J|Y|K|Z|L|M]]|9|@]|A|$]]|$1|N|3|O|5|6|7|10|8|@$J|11|K|12|L|M]]|9|@]|A|$]]|$1|P|3|Q|5|6|7|13|8|@$J|14|K|15|L|M]]|9|@]|A|$]]|$1|R|3|-4|5|6|7|16|8|@]|9|@]|A|$]]]|S|$]]

These are related to services. We all know that services keeps on running in the background and they also consume some memory to execute. 

So, as more of the application runs on android device, the device memory keeps on getting low and when the time arises, when the device memory gets critically low, the android system starts terminating processes, so as to release the memory occupied by the processes.

But you might be doing some important task with the services, that could also get terminated as the service stops. so these concepts are to tell the android system what action you want to perform when the device memory gets stable and when it is ready to relaunch the services.

The simplest explanation of these could be,

<code>START_STICKY-</code> tells the system to create a fresh copy of the service, when sufficient memory is available, after it recovers from low memory. Here you will lose the results that might have computed before.

<code>START_NOT_STICKY-</code> tells the system not to bother to restart the service, even when it has sufficient memory.

<code>START_REDELIVER_INTENT-</code> tells the system to restart the service after the crash and also redeliver the intents that were present at the time of crash.

blocks|key|508706|text|嗯，我在你的链接里读了那条线，上面写的都是。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|508707|如果您的服务由于内存不足而被Android杀死，而Android清除了一些内存，那么.|508708|粘性：...Android将重新启动您的服务，因为设置了特定的标志。|ordered-list-item|508709|NOT_STICKY：...Android不会在意重新开始，因为标志告诉安卓它不应该麻烦。|508710|REDELIVER_INTENT：...Android将重新启动服务，并向服务的onStartCommand()重新传递相同的意图，因为再次使用标志。|offset|length|style|CODE|508711|508712|508713|entityMap^0|0|0|0|0|14|G|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|T|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|A|$]]|$1|G|3|H|5|F|7|V|8|@]|9|@]|A|$]]|$1|I|3|J|5|F|7|W|8|@$K|X|L|Y|M|N]]|9|@]|A|$]]|$1|O|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]|$1|P|3|-4|5|6|7|10|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|11|8|@]|9|@]|A|$]]]|R|$]]

Well, I read the thread in your link, and it says it all.

if your service is killed by Android due to low memory, and Android clears some memory, then...

<ol>
<li>STICKY: ...Android will restart your service, because that particular flag is set.</li>
<li>NOT_STICKY: ...Android will not care about starting again, because the flag tells Android it shouldn't bother.</li>
<li>REDELIVER_INTENT: ...Android will restart the service AND redeliver the same intent to <code>onStartCommand()</code> of the service, because, again, of the flag.</li>
</ol>

blocks|key|712681|text|这两种代码只有在手机耗尽内存并在服务完成执行之前终止服务时才有意义。START_STICKY告诉操作系统在拥有足够的内存后重新创建服务，并再次调用onStartCommand()，结果为null。START_NOT_STICKY告诉操作系统不要再重新创建服务了。还有第三个代码START_REDELIVER_INTENT，它告诉操作系统重新创建服务并将相同的意图重新传递给onStartCommand()。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|712682|本文由戴安·哈克伯恩(+Dianne+Hackborn+)撰写，比官方文档更好地解释了这一背景。|712683|来源：http://android-developers.blogspot.com.au/2010/02/service-api-changes-starting-with.html|offset|length|712684|这里的关键部分是函数返回的新结果代码，它告诉系统，如果它的进程在运行时被终止，它应该对服务做什么：|712685|START_STICKY基本上与之前的行为相同，在该行为中，服务将被“启动”并将由系统重新启动。与以前版本平台的唯一不同之处在于，如果由于其进程被终止而重新启动，则将在服务的下一个实例上调用onStartCommand()，而不是完全不调用它。使用此模式的服务应该始终检查这种情况，并对其进行适当处理。
START_NOT_STICKY说，在从onStartCreated()返回之后，如果进程被终止，没有剩余的启动命令要交付，那么服务将停止而不是重新启动。对于那些只在执行发送给它们的命令时才能运行的服务来说，这更有意义。例如，可能每15分钟启动一次服务，从警报开始轮询某个网络状态。如果它在做这件事时被杀死了，最好让它停下来，下次警报响的时候就开始。
START_REDELIVER_INTENT类似于START_NOT_STICKY，除非该服务的进程在调用stopSelf()之前被终止，否则该意图将被重新传递到它，直到它完成为止(除非经过多次尝试，它仍然无法完成，此时系统就放弃了)。这对于接收要执行的工作命令的服务非常有用，并且希望确保它们最终完成发送的每个命令的工作。|blockquote|712686|712687|entityMap|0|LINK|mutability|MUTABLE|url|http://android-developers.blogspot.com.au/2010/02/service-api-changes-starting-with.html^0|0|0|3|2G|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|V|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|W|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|X|8|@]|9|@$F|Y|G|Z|1|10]]|A|$]]|$1|H|3|I|5|6|7|11|8|@]|9|@]|A|$]]|$1|J|3|K|5|L|7|12|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|13|8|@]|9|@]|A|$]]|$1|N|3|-4|5|6|7|14|8|@]|9|@]|A|$]]]|O|$P|$5|Q|R|S|A|$T|U]]]]

Both codes are only relevant when the phone runs out of memory and kills the service before it finishes executing. START_STICKY tells the OS to recreate the service after it has enough memory and call onStartCommand() again with a null intent. START_NOT_STICKY tells the OS to not bother recreating the service again. There is also a third code START_REDELIVER_INTENT that tells the OS to recreate the service AND redelivery the same intent to onStartCommand().

This article by Dianne Hackborn explained the background of this a lot better then the official documentation.

Source: <a href="http://android-developers.blogspot.com.au/2010/02/service-api-changes-starting-with.html" rel="noreferrer">http://android-developers.blogspot.com.au/2010/02/service-api-changes-starting-with.html</a>

The key part here is a new result code returned by the function, telling the system what it should do with the service if its process is killed while it is running:

<blockquote>
 START_STICKY is basically the same as the previous behavior, where the
 service is left "started" and will later be restarted by the system.
 The only difference from previous versions of the platform is that it
 if it gets restarted because its process is killed, onStartCommand()
 will be called on the next instance of the service with a null Intent
 instead of not being called at all. Services that use this mode should
 always check for this case and deal with it appropriately.
 
 START_NOT_STICKY says that, after returning from onStartCreated(), if
 the process is killed with no remaining start commands to deliver,
 then the service will be stopped instead of restarted. This makes a
 lot more sense for services that are intended to only run while
 executing commands sent to them. For example, a service may be started
 every 15 minutes from an alarm to poll some network state. If it gets
 killed while doing that work, it would be best to just let it be
 stopped and get started the next time the alarm fires.
 
 START_REDELIVER_INTENT is like START_NOT_STICKY, except if the
 service's process is killed before it calls stopSelf() for a given
 intent, that intent will be re-delivered to it until it completes
 (unless after some number of more tries it still can't complete, at
 which point the system gives up). This is useful for services that are
 receiving commands of work to do, and want to make sure they do
 eventually complete the work for each command sent.
</blockquote>

I am unable to understand 

<ol>
<li>START_STICKY,</li>
<li>START_NOT_STICKY and </li>
<li>START_REDELIVER_INTENT </li>
</ol>

Can anyone explain clearly with examples.

I went through <a href="https://stackoverflow.com/questions/9093271/start-sticky-and-start-not-sticky">this</a> link but couldn't understand it clearly.

What is START_STICKY,START_NOT_STICKY and START_REDELIVER_INTENT Service

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我无法理解START_STICKY，START_NOT_STICKY和START_REDELIVER_INTENT有人能用例子解释清楚吗。我浏览了链接，但无法清楚地理解它。

问什么是START_STICKY、START_NOT_STICKY和START_REDELIVER_INTENT服务？
EN

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问什么是START_STICKY、START_NOT_STICKY和START_REDELIVER_INTENT服务？EN