由网友(空港里的旧少年)分享简介：谁能向我解释什么是Android系统的Ap​​p在一个正常的应用程序的好处（除了这一事实，系统应用程序不能被卸载）？特殊权限？Can somebody explain to me what are the benefits of Android System App over a "normal" app (b...

谁能向我解释什么是Android系统的Ap​​p在一个正常的应用程序的好处 （除了这一事实，系统应用程序不能被卸载）？ 特殊权限？

Can somebody explain to me what are the benefits of Android System App over a "normal" app (besides that fact that a system app cannot be uninstalled)? Special permissions?

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有一些混乱在这里。

首先，如果你说的是系统应用为摆明之一，FLAG_SYSTEM集，这一切都意味着，该应用程序位于/系统分区，这是只读的分区，基本上是固件装置。 （它只能被修改的OTA固件更新的一部分。）这些应用不能简单地除去，因为它们是在不能被修改的分区。

First, if you are talking about "system app" as just being one with FLAG_SYSTEM set, all this means is that the app is located on the /system partition, which is the read-only partition that is basically the firmware of the device. (It can only be modified as part of an OTA firmware update.) These apps can't be removed simply because they are on a partition that can't be modified.

唯一特别的超出了一个系统的应用是，有极少数的签字权限也可以授予系统映像上的任何应用程序。例如有一种允许直接与包管理器交谈安装一个应用程序（无需经过系统UI），这样的应用程序可以有;这是任何应用商店/市场$ P $的设备上对加载非常有用。

The only thing special about a system application beyond this is that there are a handful of signature permissions that can also be granted to any app on the system image. For example there is a permission to directly talk with the package manager to install an app (without going through the system UI) that such an app can have; this is useful for any app store / market pre-loaded on a device.

与所述平台证书签名是正交的概念 - 例如一个应用程序可以是在系统图像上或者安装作为第三方应用（虽然明显在几乎所有的情况下，这些来$ P $对安装）。这些应用程序可以访问一整套的低级别权限与平台进行交互。很少有应用程序都与此证书签名;它只是为核心平台的应用程序。除非你正在使用设备上的硬件供应商，您将无法访问这一点。

Being signed with the platform certificate is an orthogonal concept -- such an app can be either on the system image or installed as a third party app (though obviously in almost all cases these come pre-installed). Such apps have access to a whole suite of low-level permissions for interacting with the platform. Very few apps are signed with this certificate; it is only for core platform applications. Unless you are working with a hardware vendor on a device, you won't have access to this.

所有平台的证书（无论是提供给所有的应用程序，需要一个应用程序来与平台证书签署，或者可用于安装在系统分区应用程序）舱单平台的声明，就像任何其他应用程序的

All of the platform's certificates (whether they be available to all apps, require an app be signed with the platform cert, or are available to apps installed on the system partition) are declared by the platforms manifest, just like any other app:

http://android.git.kernel.org/?p=platform/frameworks/base.git;a=blob;f=core/res/AndroidManifest.xml