2015-02-17 76 views
-1

我需要做的是獲得特定商店中某個用戶的積分,我運行這個;從光標獲取數據

   Cursor cursor1 = myDB.checkPointss(email, name); 
       String one = cursor1.getString(cursor1.getColumnIndex("POINTS")); 

       scanText.setText("barcode resueeeelt " + one); 

這是方法;

public Cursor checkPointss(String email, String name) { 
    Cursor c = db.rawQuery("SELECT * FROM compdata WHERE EMAIL= ? AND NAME=?", new String[] {email, name}); 
    if (c != null) { 
     c.moveToFirst(); 
    } 
    return c; 

} 

我每次嘗試登錄到網頁,它試圖獲得積分崩潰?我嘗試了很多不同的代碼,但似乎沒有任何工作。

所以我只是希望它找到包含該用戶名和商店名稱的行的點,然後添加一定量的點和更新數據庫。

02-18 20:07:42.694 15570-15570/com.adventorious.quickrewards E/AndroidRuntime﹕ FATAL EXCEPTION: main 
    Process: com.adventorious.quickrewards, PID: 15570 
    java.lang.IllegalStateException: Couldn't read row 0, col -1 from CursorWindow. Make sure the Cursor is initialized correctly before accessing data from it. 
      at android.database.CursorWindow.nativeGetString(Native Method) 
      at android.database.CursorWindow.getString(CursorWindow.java:439) 
      at android.database.AbstractWindowedCursor.getString(AbstractWindowedCursor.java:51) 
      at com.adventorious.quickrewards.Scan$3.onPreviewFrame(Scan.java:155) 
      at android.hardware.Camera$EventHandler.handleMessage(Camera.java:1016) 
      at android.os.Handler.dispatchMessage(Handler.java:102) 
      at android.os.Looper.loop(Looper.java:146) 
      at android.app.ActivityThread.main(ActivityThread.java:5602) 
      at java.lang.reflect.Method.invokeNative(Native Method) 
      at java.lang.reflect.Method.invoke(Method.java:515) 
      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1283) 
      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1099) 
      at dalvik.system.NativeStart.main(Native Method) 

此作品;

public boolean checkPoints(String email, String name){ 
    Cursor c = db.rawQuery("SELECT POINTS FROM compdata WHERE EMAIL= ? AND NAME=?", new String[] {email, name}); 
    if(c.moveToFirst()) { 
     return true; 
    } else { 
     return false; 

    } 
} 

那麼,爲什麼它不能獲取數據呢?

+0

*我每次嘗試登錄到頁面,它崩潰* ..如果我在你身上,我會修復崩潰 – Blackbelt 2015-02-17 20:13:20

+0

@Blackbelt因爲點而崩潰了?幫幫我? – 2015-02-17 20:14:41

+0

我想怎麼知道它?你能發佈堆棧跟蹤嗎? – Blackbelt 2015-02-17 20:15:34

回答

1

getColumnIndex()區分大小寫,而SQL不區分大小寫。

如果表格中的列是小寫字母,則SELECT *結果集中的字母將是小寫字母,並且嘗試使用大寫字母名稱檢索它將不起作用。