android - E/SQLiteLog : (1) no such table: Cars on Android 9 Pie

Question

为什么数据库的应对不适用于 Android 9？我的实现是基于这个 example (video)。在从 4.1 到 10 的 Android 版本上一切正常，但在 9 Pie 上却不行。

这是我所做的:

fun importToApp(fileNameOnSD: String) {
        val sd = File(sdFolder)
        if (sd.canWrite()) {
            val currentDB = File(Environment.getDataDirectory(), dataTemp)
            val backupDB = File(sd, fileNameOnSD)
            if (currentDB.exists()) {
                try {
                    val src = FileInputStream(backupDB).channel
                    val dst = FileOutputStream(currentDB).channel
                    dst.transferFrom(src, 0, src.size())
                    src.close()
                    dst.close()
                } catch (e: FileNotFoundException) {
                    e.printStackTrace()
                } catch (e: IOException) {
                    e.printStackTrace()
                }
            }
        }
        copyData()
    }

    private fun copyData() {
        db.delete(TABLE, null, null)
        val dbBackup = context.openOrCreateDatabase(DB_TEMP, Context.MODE_PRIVATE, null)
        val cursor = dbBackup.query(true, TABLE, null, null, null, null, null, null, null)

        cursor.moveToFirst()
        while (!cursor.isAfterLast) {
            db.insert(TABLE, null, modelToValues(cursorToModel(cursor)))
            cursor.moveToNext()
        }
        cursor.close()
        context.deleteDatabase(dataTemp)
        utilities.toast(context.resources.getString(R.string.db_suc_imported), 0)
    } 

我还调用了该方法( as proposed here ):

override fun onOpen(db: SQLiteDatabase) {
        super.onOpen(db)
        if (Build.VERSION.SDK_INT == 28)
            db.disableWriteAheadLogging()
    }

这是Android Pie中引起的崩溃:

E/SQLiteLog: (1) no such table: Cars 
D/AndroidRuntime: Shutting down VM


    --------- beginning of crash
E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.easyapps.cryptnote, PID: 3174
    android.database.sqlite.SQLiteException: no such table: Cars (code 1 SQLITE_ERROR): , while compiling: SELECT DISTINCT * FROM Cars 
        at android.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method)
        at android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:903)
        at android.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:514)
        at android.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:588)
        at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:58)
        at android.database.sqlite.SQLiteQuery.<init>(SQLiteQuery.java:37)
        at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:46)
        at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1408)
        at android.database.sqlite.SQLiteDatabase.queryWithFactory(SQLiteDatabase.java:1255)
        at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1126)
        at com.easyapps.cryptnote.ListDatabase.copyData(CarsDatabase.kt:144)
        at com.easyapps.cryptnote.ListDatabase.importToApp(CarsDatabase.kt:137)
        at com.easyapps.cryptnote.ImportActivity$importDB$$inlined$apply$lambda$1.onClick(CarsActivity.kt:273)
        at android.view.View.performClick(View.java:6597)
        at android.view.View.performClickInternal(View.java:6574)
        at android.view.View.access$3100(View.java:778)
        at android.view.View$PerformClick.run(View.java:25885)
        at android.os.Handler.handleCallback(Handler.java:873)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:193)
        at android.app.ActivityThread.main(ActivityThread.java:6669)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
I/Process: Sending signal. PID: 3174 SIG: 9

此行 val cursor = dbBackup.query(true, TABLE, null, null, null, null, null, null, null)使应用程序崩溃。到目前为止，我在两种不同的真实 Android 设备上进行了测试，一种使用 Android Lollipop (Moto)，另一种使用 Android Pie (Samsung A40)。其他版本是虚拟的。最有趣的是它可以在带有 Android Pie 的三星上运行，但不能在带有 Android Pie 的虚拟设备上运行。尽管如此，我认为三星设备是个异常(exception)，我需要在所有 Android 设备上运行，无论是真实的还是虚拟的。

Answer 1

所以，我使用第一个 answer 解决了这个问题。 .我添加了一个内部类

class TempDataBase(private val context: Context, dbName: String, version: Int) : SQLiteOpenHelper(
        context,
        dbName, null,
        version
    ) {
        override fun onCreate(db: SQLiteDatabase) {
            db.execSQL("CREATE TABLE $TABLE ($ID INTEGER PRIMARY KEY AUTOINCREMENT, $TITLE TEXT, $NOTE TEXT, $DATE TEXT);")
        }

        override fun onUpgrade(db: SQLiteDatabase, oldVersion: Int, newVersion: Int) {
            db.execSQL("DROP TABLE IF EXISTS $TABLE")
            onCreate(db)
        }

        override fun onConfigure(db: SQLiteDatabase) {
            db.disableWriteAheadLogging()
            super.onConfigure(db)
        }
    }

并在我的 copyData() 中调用它方法:

private fun copyData() {
        db.delete(TABLE, null, null)
        val dbBackup = if (Build.VERSION.SDK_INT == Build.VERSION_CODES.P) {
            SQLiteDatabase.openDatabase(TempDataBase(context, DB_TEMP, 1).readableDatabase.path, null, SQLiteDatabase.OPEN_READWRITE)
        }
        else
            context.openOrCreateDatabase(DB_TEMP, Context.MODE_PRIVATE, null)
        val cursor = dbBackup.query(true, TABLE,null,null,null,null,null,null, null)
        cursor.moveToFirst()
        while (!cursor.isAfterLast) {
            db.insert(TABLE, null, modelToValues(cursorToModel(cursor)))
            cursor.moveToNext()
        }
        cursor.close()
        db.close()
        context.deleteDatabase(dataTemp)
        utilities.toast(context.resources.getString(R.string.db_suc_imported), 0)
    }

基本上，Android P 会查找数据库并检测到该数据库不存在，而其他版本并不真正要求临时数据库必须确实存在。我的内部类创建了一个临时数据库作为缓冲区来复制 Android 9 使用的数据。

谁还在寻找解决方案，请发表评论以获取更多信息，我会尽快回复。