blocks|key|607661|text|整个过程还是仅仅是活动？|type|blockquote|depth|inlineStyleRanges|entityRanges|data|607662|Android终止进程。您可以自己处理掉活动(例如，调用finish())，当它们被垃圾收集时，Android可以将部分堆空间返回给系统。然而，Android并不是以这种方式主动地去除单个组件--这是整个过程，否则什么也不做。|unstyled|offset|length|style|CODE|607663|后续问题:我们应该倾听哪些事件，以确保我们在发生这种情况时被发出信号？|607664|当您的进程终止时，不会调用任何内容。|607665|entityMap^0|0|S|8|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@$E|Q|F|R|G|H]]|9|@]|A|$]]|$1|I|3|J|5|6|7|S|8|@]|9|@]|A|$]]|$1|K|3|L|5|D|7|T|8|@]|9|@]|A|$]]|$1|M|3|-4|5|D|7|U|8|@]|9|@]|A|$]]]|N|$]]

<blockquote>
 The entire process or just the activities?
</blockquote>

Android terminates processes. You can get rid of activities yourself (e.g., call <code>finish()</code>), and when they get garbage-collected, Android can return some of your heap space to the system. However, Android does not proactively get rid of individual components this way -- it's the entire process or nothing.

<blockquote>
 Follow up question: what events should we be listening to, to make sure we are signaled when this happens?
</blockquote>

Nothing is called when your process is terminated.

blocks|key|1327660|text|实际上，如果Android需要内存，它将终止您的整个进程。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1327661|活动被释放，并在被销毁后成为垃圾收集的候选对象，释放进程中的空间。释放进程中的空间对Android可用的内存没有影响。|1327662|Activity.onDestroy被称为最大努力.可以在不调用其onDestroy方法的情况下销毁活动。onPause得到了保证。|1327663|安卓为每个进程分配了一个优先级，一个介于-15到16之间的数字，称为oom_adj。数量越多，一个过程就越有可能被杀死。只有系统应用程序的oom_adj+<+0。当前可见的应用程序的oom_adj为0。一个进程没有UI，但是正在运行的服务将在4-5区域。不可见且没有正在运行的服务的进程具有更高的oom_adj，而不在后端堆栈中的进程的值将最高。|1327664|每个设备都有一个编译表，这是Android系统的一部分，它将oom_adj值与低内存条件相关联。例如，这个表表示，如果Android的内存降到了最后的8M，那么它应该杀死任何oom_adj为12或更高的进程。随着内存状况变得更加糟糕，Android可以用越来越低的oom_adj杀死进程。|1327665|当Android因为需要内存而扼杀您的进程时，它会使用相当于杀死-9的方法。|1327666|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|O|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|P|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|Q|8|@]|9|@]|A|$]]|$1|H|3|I|5|6|7|R|8|@]|9|@]|A|$]]|$1|J|3|K|5|6|7|S|8|@]|9|@]|A|$]]|$1|L|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|M|$]]

Android will, indeed, terminate your entire process, if it needs memory.

Activities are freed and become candidates for garbage collection after they are destroyed, freeing up space within your process. Freeing space within your process has no affect on the memory available to Android.

Activity.onDestroy is called best-effort. It is possible for an Activity to be destroyed without its onDestroy method being called. onPause is guaranteed.

Android assigns each process a priority, a number between -15 and 16, called oom_adj. The bigger the number, the more likely a process is to be killed. Only system applications have oom_adj &lt; 0. The currently visible app has an oom_adj of 0. A process with no UI, but a running service will be in the 4-5 area. A process that is not visible and that has no running service will have a higher oom_adj, and a process that is not in the back-stack will have the highest value.

Each device has a compiled-in table, part of the Android system, that associates oom_adj values with low memory conditions. This table says, for instance, that if Android gets down to its last 8 M of memory, it should kill any process with an oom_adj of, say, 12 or higher. As the memory situation gets more dire, Android is allowed to kill processes with lower and lower oom_adj.

When Android kills your process, because it needs memory, it does so with the equivalent of kill -9.

blocks|key|1327690|text|如果系统认为Android组件占用过多内存，它的进程将被终止。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1327691|但是，由于您使用的是前台服务，所以Android将尽力不扼杀您的进程，直到内存资源非常低。对于您的活动，您应该覆盖onSavedInstanceState以保存您的数据，以防您的活动在此场景中被终止。|offset|length|1327692|此外，为了使您的进程被系统杀死以回收资源，您应该尽可能地减少内存占用。您可以在两个进程中将服务和活动组件分开，因为该活动及其UI资源通常比服务占用更多的内存。通过在单独的进程中承载活动组件，可以保护您的服务不会随着活动一起被杀死。|1327693|entityMap|0|LINK|mutability|MUTABLE|url|http://developer.android.com/reference/android/app/Activity.html#onSaveInstanceState%2528android.os.Bundle%2529^0|0|1L|K|0|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Q|8|@]|9|@$D|R|E|S|1|T]]|A|$]]|$1|F|3|G|5|6|7|U|8|@]|9|@]|A|$]]|$1|H|3|-4|5|6|7|V|8|@]|9|@]|A|$]]]|I|$J|$5|K|L|M|A|$N|O]]]]

The process that hosts the Android components will be killed if system consider it using too much memory.

However, since your are using a foreground service, Android will try hard to not kill you process until the memory resource is extremely low. For you activities, you should overwrite the <a href="http://developer.android.com/reference/android/app/Activity.html#onSaveInstanceState%28android.os.Bundle%29" rel="nofollow">onSavedInstanceState</a> to save your data in case your activity is killed in this scenario.

Also, in order to keep your process being killed by system to reclaim resource, you should keep your memory footprint as small as possible. You can separate your service and the activity components in two processes, because the activity, along with its UI resource, is usually taking much memory than the service. By hosting the activity components in a separate process can protected your service from killed along with the activities.

We are developing an app that needs a foreground service to collect data. I am trying to understand how Android deals with the process and it's activities, if it is bound to a foreground service.

What can Android decide to throw out if it needs more memory? The entire process or just the activities? What is expected behavior?

Follow up question: what events should we be listening to, to make sure we are signaled when this happens? Activity.onDestroy? Is it guaranteed to be fired?

What can Android decide to throw out if it needs more memory?

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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我们正在开发一个应用程序，需要前台服务来收集数据。我试图了解Android是如何处理进程和它的活动的，如果它是绑定到前台服务的话。如果Android需要更多的内存，它能决定扔掉什么呢？整个过程还是仅仅是活动？什么是预期的行为？后续问题:我们应该倾听哪些事件，以确保我们在发生这种情况时被发出信号？Activity.onD...

问如果Android需要更多的内存，它能决定扔掉什么呢？
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问如果Android需要更多的内存，它能决定扔掉什么呢？EN