Big_Double 2016-08-05 10:15 采纳率: 20%
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用adb shell无法显示数据库中的内容,本人初学者

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public class MainActivity extends AppCompatActivity {

private MyDatabaseHelper dbHelper;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    dbHelper = new MyDatabaseHelper(this, "BookStore.db", null, 2);
    Button createDatabase = (Button)findViewById(R.id.create_database);
    Button addData = (Button)findViewById(R.id.add_data);

    createDatabase.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
            dbHelper.getWritableDatabase();
        }
    });

    addData.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
            SQLiteDatabase db = dbHelper.getWritableDatabase();
            ContentValues values = new ContentValues();
            values.put("name", "the da vinci code");
            values.put("author", "Dan Brown");
            values.put("pages", 454);
            values.put("price", 16.96);
            db.insert("Book", null, values);
            values.clear();
            values.put("name", "the lost symbol");
            values.put("author", "Dan Brown");
            values.put("pages", 510);
            values.put("price", 19.95);
            db.insert("Book", null, values);
            Log.d("MyDatabaseHelper", "insert succeed");
        }
    });
}

}

public class MyDatabaseHelper extends SQLiteOpenHelper {

public static final String CREATE_BOOK = "create table Book ("
        + "id integer primary key autoincrement, "
        + "author text, "
        + "price real, "
        + "pages integer, "
        + "name text)";
public static final String CREATE_CATEGORY = "create table Category ("
        + "id integer primary key autoincrement, "
        + "category_name text, "
        + "category_code integer)";

private Context mContext;

public MyDatabaseHelper(Context context, String name, CursorFactory factory, int version) {

    super(context, name, factory, version);
    Log.d("MyDatabaseHelper", "执行MyDatabaseHelper构造方法");
    mContext = context;

}

@Override
public void onCreate(SQLiteDatabase db) {
    Log.d("MyDatabaseHelper", "执行onCreate方法");
    db.execSQL(CREATE_BOOK);
    db.execSQL(CREATE_CATEGORY);
    Toast.makeText(mContext, "Create succeeded", Toast.LENGTH_SHORT).show();
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    Log.d("MyDatabaseHelper", "执行onUpgrade方法");
    db.execSQL("drop table if exists Book");
    db.execSQL("drop table if exists Category");
    onCreate(db);
}

}

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1条回答 默认 最新

  • dabocaiqq 2017-03-04 15:53
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