我创建了一个列表,我想提取特定 id 的所有数据,这是我尝试过的,但我无法让它工作:
public Cursor fetchById(long id) throws SQLException {
Cursor mCursor = mDb.query(true, SQLITE_TABLE, new String[] {
KEY_ROWID, KEY_MATCH, KEY_TIME, KEY_BOOKMAKERS, KEY_ODDS1 },
KEY_ROWID + "=" + id, null, null, null, null, null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
通过调试,我可以看到“光标”中的数据为:
android.database.sqlite.SQLiteCursor@41e7a1c8
我希望这将是该 ID 处其他数据的完整字符串
这是我的数据库:
这是更多的数据库信息:
这是调用该方法的活动:
选择.java
public class Choice extends Activity {
private BetsDbAdapter dbHelper;
private SimpleCursorAdapter dataAdapter;
Long value;
TextView idshow;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.choicelayout);
//Database
dbHelper = new BetsDbAdapter(this);
dbHelper.open();
Bundle extras = getIntent().getExtras();
if(extras !=null){
value = extras.getLong("id");
}
String id = String.valueOf(value);
Cursor cursor = dbHelper.fetchById(value); //Here i call the function
idshow = (TextView) findViewById(R.id.textView1);
idshow.setText(cursor);
}
这是我的数据库处理程序:
BetsDbAdapter.java
public class BetsDbAdapter {
public static final String KEY_ROWID = "_id";
public static final String KEY_MATCH = "match";
public static final String KEY_TIME = "time";
public static final String KEY_BOOKMAKERS = "bookmakers";
public static final String KEY_ODDS1 = "odds1";
private static final String TAG = "BetsDbAdapter";
private DatabaseHelper mDbHelper;
private SQLiteDatabase mDb;
private static final String DATABASE_NAME = "Bets.db";
private static final String SQLITE_TABLE = "BetTable";
private static final int DATABASE_VERSION = 1;
private final Context mCtx;
private static final String DATABASE_CREATE = "CREATE TABLE if not exists "
+ SQLITE_TABLE + " (" + KEY_ROWID
+ " integer PRIMARY KEY autoincrement," + KEY_MATCH + ","
+ KEY_TIME + "," + KEY_BOOKMAKERS + "," + KEY_ODDS1 + ","
+ " UNIQUE (" + KEY_MATCH + "));";
private static class DatabaseHelper extends SQLiteOpenHelper {
DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
Log.w(TAG, DATABASE_CREATE);
db.execSQL(DATABASE_CREATE);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
Log.w(TAG, "Upgrading database from version " + oldVersion + " to "
+ newVersion + ", which will destroy all old data");
db.execSQL("DROP TABLE IF EXISTS " + SQLITE_TABLE);
onCreate(db);
}
}
public BetsDbAdapter(Context ctx) {
this.mCtx = ctx;
}
public BetsDbAdapter open() throws SQLException {
mDbHelper = new DatabaseHelper(mCtx);
mDb = mDbHelper.getWritableDatabase();
return this;
}
public void close() {
if (mDbHelper != null) {
mDbHelper.close();
}
}
public long createBets(String match, String time, String bookmakers,
String odds1) {
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_MATCH, match);
initialValues.put(KEY_TIME, time);
initialValues.put(KEY_BOOKMAKERS, bookmakers);
initialValues.put(KEY_ODDS1, odds1);
return mDb.insert(SQLITE_TABLE, null, initialValues);
}
public Cursor fetchById(long id) throws SQLException {
Cursor mCursor = mDb.query(true, SQLITE_TABLE, new String[] {
KEY_ROWID, KEY_MATCH, KEY_TIME, KEY_BOOKMAKERS, KEY_ODDS1 },
KEY_ROWID + "=" + id, null, null, null, null, null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}