android P非systemuid应用如何通过反射调用hide接口——系统修改方案
高通8909平台，项目需要集成GMS。开机后，SetupWizard一直报错，查看log发现是调用了系统的hide方法，显示Accessing hidden method进而报错java.lang.NoSuchMethodException。
百度找到了一篇入门贴：
https://blog.csdn.net/firedancer0089/article/details/82969969
然后找了一篇科普贴：
https://developer.android.com/distribute/best-practices/develop/restrictions-non-sdk-interfaces
官方科普贴有临时调试方案：
Android 9 (API level 28)
To enable access, use the following adb commands:
adb shell settings put global hidden_api_policy_pre_p_apps 1
adb shell settings put global hidden_api_policy_p_apps 1
To reset the API enforcement policy to the default settings, use the following commands:
adb shell settings delete global hidden_api_policy_pre_p_apps
adb shell settings delete global hidden_api_policy_p_apps
You can set the integer in the API enforcement policy to one of the following values:
0: Disable all detection of non-SDK interfaces. Using this setting disables all log messages for non-SDK interface usage and prevents you from testing your app using the StrictMode API. This setting is not recommended.
1: Enable access to all non-SDK interfaces, but print log messages with warnings for any non-SDK interface usage. Using this setting also allows you to test your app using the StrictMode API.
2: Disallow usage of non-SDK interfaces that belong to either the blacklist or the greylist and are restricted for your target API level.
设置0之后，重启设备可以解决我的问题，之后就找靠谱的解决方案。
可以从官方文档看到，除了临时调试方案，还有黑名单、灰名单和白名单，但是没有写如何修改。
重点来了，仅针对QC平台，我修改的文件：
frameworks/base/data/etc/hiddenapi-package-whitelist.xml
<config>
<hidden-api-whitelisted-app package="android.ext.services" />
<hidden-api-whitelisted-app package="com.android.apps.tag" />
<hidden-api-whitelisted-app package="com.android.basicsmsreceiver" />
<hidden-api-whitelisted-app package="com.android.bookmarkprovider" />
<hidden-api-whitelisted-app package="com.android.calllogbackup" />
<hidden-api-whitelisted-app package="com.android.camera" />
<hidden-api-whitelisted-app package="com.android.car.dialer" />
<hidden-api-whitelisted-app package="com.android.car.messenger" />
<hidden-api-whitelisted-app package="com.android.car.overview" />
<hidden-api-whitelisted-app package="com.android.car.stream" />
<hidden-api-whitelisted-app package="com.android.companiondevicemanager" />
<hidden-api-whitelisted-app package="com.android.dreams.basic" />
<hidden-api-whitelisted-app package="com.android.gallery" />
<hidden-api-whitelisted-app package="com.android.launcher3" />
<hidden-api-whitelisted-app package="com.android.mtp" />
<hidden-api-whitelisted-app package="com.android.musicfx" />
<hidden-api-whitelisted-app package="com.android.packageinstaller" />
<hidden-api-whitelisted-app package="com.android.printservice.recommendation" />
<hidden-api-whitelisted-app package="com.android.printspooler" />
<hidden-api-whitelisted-app package="com.android.providers.blockednumber" />
<hidden-api-whitelisted-app package="com.android.providers.calendar" />
<hidden-api-whitelisted-app package="com.android.providers.contacts" />
<hidden-api-whitelisted-app package="com.android.providers.downloads" />
<hidden-api-whitelisted-app package="com.android.providers.downloads.ui" />
<hidden-api-whitelisted-app package="com.android.providers.media" />
<hidden-api-whitelisted-app package="com.android.providers.tv" />
<hidden-api-whitelisted-app package="com.android.providers.userdictionary" />
<hidden-api-whitelisted-app package="com.android.smspush" />
<hidden-api-whitelisted-app package="com.android.spare_parts" />
<hidden-api-whitelisted-app package="com.android.statementservice" />
<hidden-api-whitelisted-app package="com.android.storagemanager" />
<hidden-api-whitelisted-app package="com.android.systemui.plugins" />
<hidden-api-whitelisted-app package="com.android.terminal" />
<hidden-api-whitelisted-app package="jp.co.omronsoft.openwnn" />
</config>
只需要加上应用包名即可。