@UnsupportedAppUsage注释描述了什么

Question

我正在构建具有系统许可权的企业应用程序，它需要使用BluetoothAdapter类setScanMode中的功能。这是一个隐藏的API，仅适用于系统签名的apk，现在此函数上方有@UnsupportedAppUsage，任何人都可以帮助我理解此注释。

https://android.googlesource.com/platform/frameworks/base/+/master/core/java/android/bluetooth/BluetoothAdapter.java

Answer 1

如果我们转到注释源：

/**
 * Indicates that a class member, that is not part of the SDK, is used by apps.
 * Since the member is not part of the SDK, such use is not supported.
 *
 * <p>This annotation acts as a heads up that changing a given method or field
 * may affect apps, potentially breaking them when the next Android version is
 * released. In some cases, for members that are heavily used, this annotation
 * may imply restrictions on changes to the member.
 *
 * <p>This annotation also results in access to the member being permitted by the
 * runtime, with a warning being generated in debug builds.
 *
 * <p>For more details, see go/UnsupportedAppUsage.
 *
 * {@hide}
 */

基本上，这意味着它正在被应用程序使用，即使它在技术上不是 SDK 的一部分，因此不受支持。对于任何为 AOSP 做出贡献的人来说，这似乎更像是一个警告，而不是您需要过多担心的事情。

Answer 2

上述注释来源描述是正确的。现在，我的 Pie 代码中出现了一个异常，而以前则没有。我正在通过 TextView.class 中的某些字段设置光标处理程序颜色，这些字段现在不受支持，并导致在无法在 Pie 中设置句柄颜色的情况下发生异常。这不仅仅是一个警告。