android - 在 Android sqlite 中创建数据库失败

Question

运行最新版本的 Android Studio。项目是为 API 级别 23 及更高级别（Marshmallow）构建的，并使用 Pixel XL 模拟器。我已在 Manifest 中授予权限并在运行时获得写访问权限（根据 API 23 及更高版本的要求）

有一个按钮连接到这个

public void createDatabase(View view) {
    String[] permissions = {Manifest.permission.WRITE_EXTERNAL_STORAGE};
    requestPermissions(permissions, 1); 
}

我在 AndroidManifest.xml 中也有这个

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

这是我的权限授予代码

@Override

public void onRequestPermissionsResult(int requestCode, String 
                                      permissions[], int[] grantResults) {
  switch (requestCode) {
    case 1:
        if(grantResults[0] == PackageManager.PERMISSION_GRANTED){
            DbUtil.CreateDb(getApplicationContext().getApplicationInfo().dataDir + "/databases/game360.db");

        }
        else{
            //Permission denied.
        }
        break;
  }
}

这是 DBUtil.CreateDb

public static void CreateDb(String dbPath){
    SQLiteDatabase db = SQLiteDatabase.openOrCreateDatabase(dbPath, null);
    db.execSQL("CREATE TABLE if not exists user (id INTEGER PRIMARY KEY AUTOINCREMENT, " +
            "username VARCHAR NOT NULL unique, firstName VARCHAR NOT NULL, lastName VARCHAR NOT NULL)");
    ContentValues values = new ContentValues();
    values.put("username", "jj678");
    values.put("firstName", "brad");
    values.put("lastName", "pitt");
    db.insert("user",null, values);
    db.close();
}

当我在模拟器上运行应用程序并单击按钮时，我会按预期获得权限弹出窗口。在我授予权限 o 后，创建数据库被调用并且它失败并出现以下堆栈跟踪（错误代码 14）。知道为什么吗？

02-23 17:44:39.347 19358-19358/com.jtech.game360 E/SQLiteLog: (14) cannot open file at line 31278 of [2ef4f3a5b1]
02-23 17:44:39.347 19358-19358/com.jtech.game360 E/SQLiteLog: (14) os_unix.c:31278: (2) open(/data/user/0/com.jtech.game360/databases/game360.db) - 
02-23 17:44:39.348 19358-19358/com.jtech.game360 E/SQLiteDatabase: Failed to open database '/data/user/0/com.jtech.game360/databases/game360.db'.
    android.database.sqlite.SQLiteCantOpenDatabaseException: unknown error (code 14): Could not open database
        at android.database.sqlite.SQLiteConnection.nativeOpen(Native Method)
        at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:207)
        at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:191)
        at android.database.sqlite.SQLiteConnectionPool.openConnectionLocked(SQLiteConnectionPool.java:463)
        at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:185)
        at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:177)
        at android.database.sqlite.SQLiteDatabase.openInner(SQLiteDatabase.java:806)
        at android.database.sqlite.SQLiteDatabase.open(SQLiteDatabase.java:791)
        at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:694)
        at android.database.sqlite.SQLiteDatabase.openOrCreateDatabase(SQLiteDatabase.java:709)
        at com.jtech.game360.DbUtil.CreateDb(DbUtil.java:13)
        at com.jtech.game360.Main2Activity.onRequestPermissionsResult(Main2Activity.java:52)
        at android.app.Activity.dispatchRequestPermissionsResult(Activity.java:6553)
        at android.app.Activity.dispatchActivityResult(Activity.java:6432)

标签： androidsqlite

Answer 1

好像你缺少databases文件夹。尝试：

public static void CreateDb(String dbPath){
    File f = new File(dbPath);
    f.getParentFile().mkdirs();
    SQLiteDatabase db = SQLiteDatabase.openOrCreateDatabase(dbPath, null);
    // ...
}