SQLite数据库rowid失败

Question

我一直在制作一个在线教程中的应用程序，在其中我正在制作一个用于存储女孩性感的数据库。目前，它必须能够存储数据并查看数据。一切都很好，只是当我显示每个条目时，属于它们的行id都是NULL。我试着把它固定了两天，但到目前为止我还没有运气。我还是一个新手，有经验的人能告诉我如何解决这个问题吗？

主要活动如下：

public class SQLiteExample extends Activity implements OnClickListener {
Button sqlUpdate, sqlView, sqlModify, sqlGetInfo, sqlDelete;
EditText sqlName, sqlHotness, sqlRow;
@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.sqliteexample);
    initiate();
}
@Override
public void onClick(View v) {
    // TODO Auto-generated method stub
    switch (v.getId()){
    case R.id.bSQLUpdate:
        boolean didItWork = true;
        try{
        String name = sqlName.getText().toString();
        String hotness = sqlHotness.getText().toString();
        HotOrNot entry = new HotOrNot(SQLiteExample.this);
        entry.open();
        entry.createEntry(name, hotness);
        entry.close();
        }catch(Exception e){
            didItWork = false;
        }finally{
            if (didItWork){
                print("YESSSS", "it's working!");
            }
            else{
                print("NOOOOO", "Something went wrong");
            }
        }
        break;
    case R.id.bSQLOpenView:
        Intent openView = new Intent(SQLiteExample.this, SQLView.class);
        startActivity(openView);
        return;
    case R.id.bgetInfo:
        String s = sqlRow.getText().toString();
        long l = Long.parseLong(s);
        HotOrNot hon = new HotOrNot(this);
        hon.open();
        String returnedName = hon.getName(l);
        String returnedHotness = hon.getHotness(l);
        hon.close();
        sqlName.setText(returnedName);
        sqlHotness.setText(returnedHotness);
        break;
    }
}
private void initiate() {
    sqlUpdate = (Button) findViewById(R.id.bSQLUpdate);
    sqlView = (Button) findViewById(R.id.bSQLOpenView);
    sqlModify = (Button) findViewById(R.id.bSQLmodify);
    sqlGetInfo = (Button) findViewById(R.id.bgetInfo);
    sqlDelete = (Button) findViewById(R.id.bSQLdelete);
    sqlName = (EditText) findViewById(R.id.etSQLName);
    sqlHotness = (EditText) findViewById(R.id.etSQLHotness);
    sqlRow = (EditText) findViewById(R.id.etSQLrowInfo);

    sqlView.setOnClickListener(this);
    sqlUpdate.setOnClickListener(this);
    sqlModify.setOnClickListener(this);
    sqlGetInfo.setOnClickListener(this);
    sqlDelete.setOnClickListener(this);
}
public void print(String title, String message){
    Dialog d = new Dialog(this);
    d.setTitle(title);
    TextView tv = new TextView(this);
    tv.setText(message);
    d.setContentView(tv);
    d.show();
};
}

数据库类：

public class HotOrNot {
public static final String KEY_ROWID = "_id";
public static final String KEY_NAME = "persons_name";
public static final String KEY_HOTNESS = "persons_hotness";
private static final String DATABASE_NAME = "HotOrNotdb";
private static final String DATABASE_TABLE = "peopleTable";
private static final int DATABASE_VERSION = 1;
private DbHelper ourHelper;
private final Context ourContext;
private SQLiteDatabase ourDatabase;
private static class DbHelper extends SQLiteOpenHelper{
    public DbHelper(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
        // TODO Auto-generated constructor stub
    }
    @Override
    public void onCreate(SQLiteDatabase db) {
        // TODO Auto-generated method stub
        db.execSQL("CREATE TABLE " + DATABASE_TABLE + " (" +
                KEY_ROWID + " INTEGER PRIMARY_KEY AUTOINCREMENT, " + 
                KEY_NAME + " TEXT NOT NULL, " + 
                KEY_HOTNESS + " TEXT NOT NULL);"                    
        );
    }
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // TODO Auto-generated method stub
        db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE);
        onCreate(db);
    }
}
public HotOrNot(Context c){
    ourContext = c;
}
public HotOrNot open() throws SQLException{
    ourHelper = new DbHelper(ourContext);
    ourDatabase = ourHelper.getWritableDatabase();
    return this;
}
public void close(){
    ourHelper.close();
}
public long createEntry(String name, String hotness) {
    // TODO Auto-generated method stub
    ContentValues cv = new ContentValues();
    cv.put(KEY_NAME, name);
    cv.put(KEY_HOTNESS, hotness);
    return ourDatabase.insert(DATABASE_TABLE, null, cv);
}
public String getData() {
    // TODO Auto-generated method stub
    String[] columns = new String[]{KEY_ROWID, KEY_NAME, KEY_HOTNESS};
    Cursor c = ourDatabase.query(DATABASE_TABLE, columns, null, null, null, null, null);
    String result = "";
    int iRow = c.getColumnIndex(KEY_ROWID);
    int iName = c.getColumnIndex(KEY_NAME);
    int iHotness = c.getColumnIndex(KEY_HOTNESS);
    for(c.moveToFirst(); !c.isAfterLast(); c.moveToNext()){
        result = result + c.getString(iRow) + " " + c.getString(iName) + " " + c.getString(iHotness) + "n";
    }
    return result;
}
}

查看活动：

public class SQLView extends Activity implements OnClickListener{
TextView tv;
Button back;
@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.sqlview);
    initiate();
    HotOrNot info = new HotOrNot(this);
    info.open();
    String data = info.getData();
    info.close();
    tv.setText(data);
}
private void initiate(){
    tv = (TextView) findViewById(R.id.tvSQLInfo);
    back = (Button) findViewById(R.id.bBack);
    back.setOnClickListener(this);
}
@Override
public void onClick(View v) {
    // TODO Auto-generated method stub
    Intent back = new Intent(SQLView.this, SQLiteExample.class);
    startActivity(back);
    return;
};
}

提前感谢！

Answer 1

存在SQL语法错误。更改

KEY_ROWID + " INTEGER PRIMARY_KEY AUTOINCREMENT, "

至

KEY_ROWID + " INTEGER PRIMARY KEY AUTOINCREMENT, "

即使下划线成为空格。

卸载您的应用程序，以便再次调用onCreate()。由于您并没有看到有关语法的错误，所以此版本的SQL并没有运行。