Android Espresso java.lang.SecurityException: 权限 android.permission.SYSTEM_ALERT_WINDOW 不是可更改的权限类型

Question

我有一个 Espresso 脚本需要 SYSTEM_ALERT_WINDOW 权限。我使用以下代码授予所有测试脚本的权限：

@Rule public GrantPermissionRule permissionRule = GrantPermissionRule.grant(Manifest.permission.SYSTEM_ALERT_WINDOW, Manifest.permission.CAMERA,
        Manifest.permission.WRITE_EXTERNAL_STORAGE);

我有一个特殊的 Android包含权限的测试用例清单。

<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />

这适用于来自不同品牌和 Android 版本的大多数设备，从 Android 5.X 到 Android 8.x（大约 15+ 设备).但是，在我的 Android 6.0 华为 P8 Lite 上，出现以下错误：

junit.framework.AssertionFailedError: Failed to grant permissions, see logcat for details
    at junit.framework.Assert.fail(Assert.java:50)
    at android.support.test.runner.permission.PermissionRequester.requestPermissions(PermissionRequester.java:110)
    at android.support.test.rule.GrantPermissionRule$RequestPermissionStatement.evaluate(GrantPermissionRule.java:128)
    at org.junit.rules.RunRules.evaluate(RunRules.java:20)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access[=14=]0(ParentRunner.java:58)
    at org.junit.runners.ParentRunner.evaluate(ParentRunner.java:268)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
    at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.junit.runners.Suite.runChild(Suite.java:128)
    at org.junit.runners.Suite.runChild(Suite.java:27)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access[=14=]0(ParentRunner.java:58)
    at org.junit.runners.ParentRunner.evaluate(ParentRunner.java:268)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:115)
    at android.support.test.internal.runner.TestExecutor.execute(TestExecutor.java:56)
    at android.support.test.runner.AndroidJUnitRunner.onStart(AndroidJUnitRunner.java:384)
    at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:1890)

当我检查 logcat 时，显示了以下附加错误：

I/GrantPermissionCallable: Permission: android.permission.WRITE_EXTERNAL_STORAGE is already granted!
I/GrantPermissionCallable: Permission: android.permission.CAMERA is already granted!
I/UiAutomationShellCmd: Requesting permission: pm grant [PACKAGE_NAME_MY_APP] android.permission.SYSTEM_ALERT_WINDOW

E/GrantPermissionCallable: Permission: android.permission.SYSTEM_ALERT_WINDOW cannot be granted!

java.lang.SecurityException: Permission android.permission.SYSTEM_ALERT_WINDOW is not a changeable permission type
    at com.android.server.pm.PackageManagerService.enforceDeclaredAsUsedAndRuntimeOrDevelopmentPermission(PackageManagerService.java:3665)
    at com.android.server.pm.PackageManagerService.grantRuntimePermission(PackageManagerService.java:3698)
    at android.content.pm.IPackageManager$Stub.onTransact(IPackageManager.java:398)
    at com.android.server.pm.PackageManagerService.onTransact(PackageManagerService.java:2807)
    at com.android.server.pm.HwPackageManagerService.onTransact(HwPackageManagerService.java:506)
    at android.os.Binder.execTransact(Binder.java:453)

我还尝试在设备上手动更改测试应用程序和待测试应用程序的 'display over other apps' 权限。但这也没有改变任何东西。

当我从 GrantPermissionRule 中删除 SYSTEM_ALERT_WINDOW 权限时，所有其他测试 运行 正常。 我不明白为什么这会在某些设备上失败。

我使用以下网站进行研究，但其中 none 个有用：

• Android permission code
• PackageManagerService Android code

Answer 1

我做了以下事情来解决这个问题。首先，我将以下行添加到 Espresso AndroidManifest

<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />

我没有将权限规则添加到我的所有测试用例中，而是将其添加到特定的测试用例中。

@Rule public GrantPermissionRule grantPermissionRule = GrantPermissionRule.grant(Manifest.permission.SYSTEM_ALERT_WINDOW);

如果设备无法绘制叠加层，我将忽略测试。

@Before
public void shouldPerformTest()
{
    boolean shouldPerformTest = true;
    if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M)
    {
        shouldPerformTest = Settings.canDrawOverlays(getContext());
    }

    Assume.assumeTrue(shouldPerformTest);
}