为什么没有sqlite错误代码

Question

为什么我没有得到SQLite失败的错误代码？我想创建一个数据库，并得到以下堆栈跟踪（当然，跟踪的顶部）：

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) 

我的代码工作在模拟器中，工作在一台Nexus 7，但没有其他设备上

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); 
    } 

下面是第二次尝试一个完整的日志。这与第一个有点不同，但仍然没有错误代码。

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，这很愚蠢。如果连接了设备并选择了“USB存储”连接，则SD卡将无法访问。道德故事：如果您的应用访问SD卡，请勿启用“USB存储”。

尽管如此，Android的应发出错误代码 - 我会提交一个bug。