我有兩個類,我的主類和另一個用於處理sqlite。我遇到的問題是當它到達主類的db.open()時崩潰,我不知道爲什麼。Android的SQLite開放數據庫崩潰
主類:
public class RingerSchedule extends Activity
{
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
DBAdapter db = new DBAdapter(this);
db.open(); //crash!
//more stuff
}
}
源碼類:
public class DBAdapter
{
public static final String KEY_ROWID = "id";
public static final String KEY_TO = "to";
public static final String KEY_FROM = "from";
public static final String KEY_DAY = "day";
public static final String KEY_FUNCTION = "function";
private static final String TAG = "DBAdapter";
private static final String DATABASE_NAME = "myDB";
private static final String DATABASE_TABLE = "schedules";
private static final int DATABASE_VERSION = 1;
private final Context context;
private DatabaseHelper DBHelper;
private SQLiteDatabase db;
public DBAdapter(Context ctx)
{
this.context = ctx;
DBHelper = new DatabaseHelper(context);
}
private static class DatabaseHelper extends SQLiteOpenHelper
{
DatabaseHelper(Context context)
{
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db)
{
db.execSQL("CREATE TABLE "
+ DATABASE_TABLE
+ " (id INT PRIMARY KEY AUTOINCREMENT, to TEXT,"
+ " from TEXT, day TEXT"
+ " function TEXT);");
}
@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 titles");
onCreate(db);
}
}
//opens the database
public DBAdapter open() throws SQLException
{
this.db = DBHelper.getWritableDatabase();
return this;
}
//closes the database
public void close()
{
DBHelper.close();
}
//insert a schedule into the database
public long insertSchedule(String from, String to, String day, String function)
{
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_TO, to);
initialValues.put(KEY_FROM, from);
initialValues.put(KEY_DAY, day);
initialValues.put(KEY_FUNCTION, function);
return db.insert(DATABASE_TABLE, null, initialValues);
}
//deletes a particular schedule
public boolean deleteSchedule(long Id)
{
return db.delete(DATABASE_TABLE, KEY_ROWID + "=" + Id, null) > 0;
}
//retrieves all the schedules
public Cursor getAllSchedules()
{
return db.query(DATABASE_TABLE, new String[] {KEY_ROWID, KEY_TO, KEY_FROM, KEY_DAY, KEY_FUNCTION}, null, null, null, null, null, null);
}
//updates a schedule
public boolean updateSchedule(long Id, String to, String from, String day, String function)
{
ContentValues args = new ContentValues();
args.put(KEY_TO, to);
args.put(KEY_FROM, from);
args.put(KEY_DAY, day);
args.put(KEY_FUNCTION, function);
return db.update(DATABASE_TABLE, args, KEY_ROWID + "=" + Id, null) > 0;
}
}
你能詳細解釋崩潰嗎?它是一個系統重新啓動,異常(如果是這樣,什麼是堆棧跟蹤)等等。你可以看看任何日誌或任何 – 2010-09-11 18:05:05
Im有點新的android開發,所以我不知道如何獲取日誌或stacktrace。 – Woody 2010-09-11 20:37:42
嘗試打開一個終端,並寫在那裏:adb logcat – 2010-09-11 22:20:15