爲什麼沒有sqlite錯誤代碼

Question

爲什麼我沒有得到SQLite失敗的錯誤代碼？我想創建一個數據庫，並得到以下堆棧跟蹤（當然，跟蹤的頂部）：

E/SqliteDatabaseCpp(11974): sqlite3_open_v2 
("/mnt/sdcard/myapp/mydatabase.db", &handle, 6, NULL) failed 
E/SQLiteDatabase(11974): Failed to open the database. closing it. 
E/SQLiteDatabase(11974): android.database.sqlite.SQLiteCantOpenDatabaseException: unable to open database file 
E/SQLiteDatabase(11974): at android.database.sqlite.SQLiteDatabase.dbopen(Native Method) 

我的代碼工作在模擬器中，工作在一臺Nexus 7，但沒有其他設備上

public SQLiteDatabase openOrCreateDatabase (String name, int mode, 
               SQLiteDatabase.CursorFactory factory, 
               DatabaseErrorHandler errorHandler) 
    { 
    File f = getDatabasePath (name); 
    System.out.println ("opening db: " + f.getPath()); 
    return super.openOrCreateDatabase (f.getPath(), mode, factory, errorHandler); 
    } 

下面是第二次嘗試一個完整的日誌。這與第一個有點不同，但仍然沒有錯誤代碼。

W/dalvikvm(3314): threadid=1: thread exiting with uncaught exception (group=0x40a801f8) 
E/AndroidRuntime(3314): FATAL EXCEPTION: main 
E/AndroidRuntime(3314): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.myapp.myapp/com.myapp.myapp.main.MainActivity}: android.database.sqlite.SQLiteCantOpenDatabaseException: unable to open database file 
E/AndroidRuntime(3314): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1956) 
E/AndroidRuntime(3314): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981) 
E/AndroidRuntime(3314): at android.app.ActivityThread.access$600(ActivityThread.java:123) 
E/AndroidRuntime(3314): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147) 
E/AndroidRuntime(3314): at android.os.Handler.dispatchMessage(Handler.java:99) 
E/AndroidRuntime(3314): at android.os.Looper.loop(Looper.java:137) 
E/AndroidRuntime(3314): at android.app.ActivityThread.main(ActivityThread.java:4424) 
E/AndroidRuntime(3314): at java.lang.reflect.Method.invokeNative(Native Method) 
E/AndroidRuntime(3314): at java.lang.reflect.Method.invoke(Method.java:511) 
E/AndroidRuntime(3314): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:812) 
E/AndroidRuntime(3314): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:579) 
E/AndroidRuntime(3314): at dalvik.system.NativeStart.main(Native Method) 
E/AndroidRuntime(3314): Caused by: android.database.sqlite.SQLiteCantOpenDatabaseException: unable to open database file 
E/AndroidRuntime(3314): at android.database.sqlite.SQLiteDatabase.dbopen(Native Method) 
E/AndroidRuntime(3314): at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:1013) 
E/AndroidRuntime(3314): at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:986) 
E/AndroidRuntime(3314): at android.database.sqlite.SQLiteDatabase.openOrCreateDatabase(SQLiteDatabase.java:1051) 
E/AndroidRuntime(3314): at android.app.ContextImpl.openOrCreateDatabase(ContextImpl.java:782) 
E/AndroidRuntime(3314): at android.content.ContextWrapper.openOrCreateDatabase(ContextWrapper.java:221) 
E/AndroidRuntime(3314): at android.content.ContextWrapper.openOrCreateDatabase(ContextWrapper.java:221) 
E/AndroidRuntime(3314): at com.myapp.myapp.dbaccess.DatabaseContext.openOrCreateDatabase(DbHelper.java:63) 
E/AndroidRuntime(3314): at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:157) 
E/AndroidRuntime(3314): at com.myapp.myapp.dbaccess.DbHelper.getDb(DbHelper.java:184) 
E/AndroidRuntime(3314): at com.myapp.myapp.dbaccess.DbHelper.getZRoot(DbHelper.java:650) 
E/AndroidRuntime(3314): at com.myapp.myapp.dbaccess.ZNodeCache.getRequiredNodes(ZNodeCache.java:37) 
E/AndroidRuntime(3314): at com.myapp.myapp.dbaccess.ZNodeCache.<init>(ZNodeCache.java:22) 
E/AndroidRuntime(3314): at com.myapp.myapp.main.MainActivity.onCreate(MainActivity.java:81) 
E/AndroidRuntime(3314): at android.app.Activity.performCreate(Activity.java:4465) 
E/AndroidRuntime(3314): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049) 
E/AndroidRuntime(3314): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920) 
E/AndroidRuntime(3314): ... 11 more 

Answer 1

嗯，這很愚蠢。如果連接了設備並選擇了「USB存儲」連接，則SD卡將無法訪問。道德故事：如果您的應用訪問SD卡，請勿啓用「USB存儲」。

儘管如此，Android的應發出錯誤代碼 - 我會提交一個bug。