在测试用例 espresso 之前清除数据库

我使用 espresso 来清除我的应用程序中的数据库 我像这样设置活动

@Rule
@JvmField
val activity = ActivityTestRule<PhotoPrinterActivity>(PhotoPrinterActivity::class.java,false,false)

这是我之前的功能

@Before
open fun setup() {
    clearDatabase()
    activity.launchActivity(null)
    // Waiting for start app success fully

}

这是我清晰的数据库代码

fun clearDatabase() {
    val databaseList = InstrumentationRegistry.getInstrumentation().targetContext.databaseList()
    for (database in databaseList) {

        // when transaction rollback files exists they are always locked so we can't delete them
        if (database.contains(".db-journal")) {
            InstrumentationRegistry.getTargetContext().deleteDatabase(database)
            continue
        }

        // when using transaction write ahead logging then this db files are listed but often they don't exist
        if (database.contains(".db-wal") || database.contains(".db-shm")) {
            InstrumentationRegistry.getTargetContext().deleteDatabase(database)
            continue
        }
        Log.v("EspressoMacchiato", "deleting " + database)
        var databasePath = InstrumentationRegistry.getInstrumentation().targetContext.getDatabasePath(database)
        if (databasePath.exists()) {
            InstrumentationRegistry.getInstrumentation().targetContext.deleteDatabase(database)
        }
    }

}

问题是当清除数据库成功并执行将一些数据添加到数据库时，

android.database.sqlite.SQLiteReadOnlyDatabaseException: attempt to write a readonly database (code 1032)
at android.database.sqlite.SQLiteConnection.nativeExecuteForLastInsertedRowId(Native Method)
at android.database.sqlite.SQLiteConnection.executeForLastInsertedRowId(SQLiteConnection.java:786)
at android.database.sqlite.SQLiteSession.executeForLastInsertedRowId(SQLiteSession.java:788)

任何人请帮助我！非常感谢！

Use @课前 http://junit.sourceforge.net/javadoc/org/junit/BeforeClass.html and 仪器注册中心 https://developer.android.com/reference/android/support/test/InstrumentationRegistry.html在您的 espresso 测试中删除数据库：

@BeforeClass
public static void beforeClass() {
    InstrumentationRegistry.getTargetContext().deleteDatabase("database_name");
}

为了防止同时执行多个浓缩咖啡测试时出现错误，请使用Android 测试协调器 https://developer.android.com/training/testing/junit-runner.html#using-android-test-orchestrator。它将分别执行所有这些。