Question

我使用以下代码从db表中检索值。

public List<String> getProcedure() {
    List<String> labels = new ArrayList<String>();

    String selectQuery = "SELECT * FROM " + TABLENAME;

    SQLiteDatabase db = this.getReadableDatabase();

    Cursor cursor = db.rawQuery(selectQuery, null);
    Log.d("before", "if");

    if (cursor.moveToFirst()) {
        Log.d("inside", "if");
        while (cursor.moveToNext()) {
            Log.d("inside", "while");
            labels.add(cursor.getString(1));
        }
    }       
    cursor.close();
    db.close();     
    return labels;
}

我从来没有在logcat中获取“if if”中的日志消息。这是什么意思？

我在表格中有数据，因此无法检索它！我该如何纠正？请帮忙!!

我的堆栈跟踪：

E/SensorManager(6951): thread start
D/SensorManager(6951): registerListener :: handle = 4  name= MPL accel delay= 200000            Listener= android.view.OrientationEventListener$SensorEventListenerImpl@4207eb60
D/before(6951): if
D/SensorManager(6951): unregisterListener::  Listener=     android.view.OrientationEventListener$SensorEventListenerImpl@4207eb60
D/Sensors(6951): Remain listener = Sending .. normal delay 200ms
I/Sensors(6951): sendDelay --- 200000000
D/SensorManager(6951): JNI - sendDelay
I/SensorManager(6951): Set normal delay = true
D/SensorManager(6951): registerListener :: handle = 4  name= MPL accel delay= 200000     Listener= android.view.OrientationEventListener$SensorEventListenerImpl@4207eb60
I/Adreno200-EGLSUB(6951): <ConfigWindowMatch:2087>: Format RGBA_8888.
E/SpannableStringBuilder(6951): SPAN_EXCLUSIVE_EXCLUSIVE spans cannot have a zero length
E/SpannableStringBuilder(6951): SPAN_EXCLUSIVE_EXCLUSIVE spans cannot have a zero length

cursor.moveToFirst（）始终返回false

0 个答案: