java - SQLite 没有在 Android studio 中创建任何表

Question

嗨，我正在尝试制作抽奖表，但是我确实创建了数据库，但没有创建表，运行面板显示我创建了它，但 sqlite 浏览器显示其中没有任何内容。这是代码:在数据库java中:

        public void onCreate(SQLiteDatabase db)
    {

        // Note the use of super, which calls the constructor of the SQLiteOpenHelper class,
        // which does the actual work of opening the database.
        Log.d(TAG, "DatabaseHelper onCreate");
        Log.d(TAG, RaffleTable.CREATE_STATEMENT);
        db.execSQL(RaffleTable.CREATE_STATEMENT);

    }

在 raffletalbe.java 中:

public class RaffleTable {

public static final String TABLE_NAME = "Raffle";

public static final String KEY_ID = "raffle_id";
public static final String KEY_NAME = "raffle_name";
public static final String KEY_PRICE = "price";
public static final String KEY_START = "raffle_start";
public static final String KEY_END = "raffle_end";
public static final String KEY_DESCRIPTION = "raffle_description";
public static final String KEY_TYPE = "raffle_type";
public static final String KEY_PRIZE = "raffle_prize";
public static final String KEY_LIMIT = "raffle_limit";

public static final String CREATE_STATEMENT = "CREATE TABLE "
        + TABLE_NAME
        + " (" + KEY_ID + " integer primary key autoincrement, "
        + KEY_NAME + " string not null, "
        + KEY_DESCRIPTION + " string, "
        + KEY_START + " string not null, "
        + KEY_END + " string not null, "
        + KEY_TYPE +  " integer not null, "
        + KEY_LIMIT + " integer, "
        + KEY_PRIZE + " String, "
        + KEY_PRICE + " real);";

运行面板中显示的内容:

D/RaffleDatabase: DatabaseHelper onCreate
CREATE TABLE Raffle (raffle_id integer primary key autoincrement, raffle_name string not null, raffle_description string, raffle_start string not null, raffle_end string not null, raffle_type integer not null, raffle_limit integer, raffle_prize String, price real);

这是我用来插入表格的代码:

        Raffle Ruffle1 = new Raffle();
    Ruffle1.setRuffleDes("742 Evergreen Terrace");
    Ruffle1.setRuffleEnd("20190102");
    Ruffle1.setRuffleStart("20190101");
    Ruffle1.setRuffleLimit(5);
    Ruffle1.setRuffleName("testing");
    Ruffle1.setRufflePrize("cooper");
    Ruffle1.setRuffleType("Normal");
    Ruffle1.setRufflePrice(1000);

    Raffle Ruffle2 = new Raffle();
    Ruffle2.setRuffleDes("742 Evergreen Terrace");
    Ruffle2.setRuffleEnd("20190102");
    Ruffle2.setRuffleStart("20190101");
    Ruffle2.setRuffleLimit(5);
    Ruffle2.setRuffleName("testing");
    Ruffle2.setRufflePrize("cooper");
    Ruffle2.setRuffleType("Normal");
    Ruffle2.setRufflePrice(1000);

    RaffleTable.insert(db, Ruffle1);
    RaffleTable.insert(db, Ruffle2);

Answer 1

你的代码没有任何问题。您只需将更新后的文件放入浏览器中即可。可能您的浏览器正在读取旧文件，这就是您无法读取更新内容的原因。