Question

I have several methods for getting a record in my app

But for some reason this one keeps giving me FC !
I’m using the following method to get the Cursor :

Cursor c=helper.getRecordById(num);

Which is implemented as follows :

public Cursor getRecordById(int rowId) {
    String rowIDs=""+rowId;
    String SelectById = "SELECT id, OrderName, OrderLink, DateYear, DateMonth, DateDay, OrderPrice FROM Orders WHERE id=?";
    String[] args={rowIDs};
    return(getReadableDatabase().rawQuery(SelectById, args));
}

I have tried also without converting the Int to String but i just left it this way.. get the same error for both ways.

Whenever i get to the following line :

String name=c.getString(c.getColumnIndexOrThrow("OrderName"));

I get the FC.
The GetColumnIndex works just fine… i’ve tested it exclusively.
But the getString throws the error. :

06-02 21:07:13.656: W/KeyCharacterMap(4329): Using default keymap: /system/usr/keychars/qwerty.kcm.bin
06-02 21:07:16.006: D/AndroidRuntime(4329): Shutting down VM
06-02 21:07:16.006: W/dalvikvm(4329): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
06-02 21:07:16.026: E/AndroidRuntime(4329): FATAL EXCEPTION: main
06-02 21:07:16.026: E/AndroidRuntime(4329): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.Sagi.MyOrders/com.Sagi.MyOrders.DisplayRecord}: android.database.CursorIndexOutOfBoundsException: Index -1 requested, with a size of 0
06-02 21:07:16.026: E/AndroidRuntime(4329):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
06-02 21:07:16.026: E/AndroidRuntime(4329):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
06-02 21:07:16.026: E/AndroidRuntime(4329):     at android.app.ActivityThread.access$2300(ActivityThread.java:125)
06-02 21:07:16.026: E/AndroidRuntime(4329):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
06-02 21:07:16.026: E/AndroidRuntime(4329):     at android.os.Handler.dispatchMessage(Handler.java:99)
06-02 21:07:16.026: E/AndroidRuntime(4329):     at android.os.Looper.loop(Looper.java:123)
06-02 21:07:16.026: E/AndroidRuntime(4329):     at android.app.ActivityThread.main(ActivityThread.java:4627)
06-02 21:07:16.026: E/AndroidRuntime(4329):     at java.lang.reflect.Method.invokeNative(Native Method)
06-02 21:07:16.026: E/AndroidRuntime(4329):     at java.lang.reflect.Method.invoke(Method.java:521)
06-02 21:07:16.026: E/AndroidRuntime(4329):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
06-02 21:07:16.026: E/AndroidRuntime(4329):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
06-02 21:07:16.026: E/AndroidRuntime(4329):     at dalvik.system.NativeStart.main(Native Method)
06-02 21:07:16.026: E/AndroidRuntime(4329): Caused by: android.database.CursorIndexOutOfBoundsException: Index -1 requested, with a size of 0
06-02 21:07:16.026: E/AndroidRuntime(4329):     at android.database.AbstractCursor.checkPosition(AbstractCursor.java:580)
06-02 21:07:16.026: E/AndroidRuntime(4329):     at android.database.AbstractWindowedCursor.checkPosition(AbstractWindowedCursor.java:214)
06-02 21:07:16.026: E/AndroidRuntime(4329):     at android.database.AbstractWindowedCursor.getString(AbstractWindowedCursor.java:41)
06-02 21:07:16.026: E/AndroidRuntime(4329):     at com.Sagi.MyOrders.DisplayRecord.onCreate(DisplayRecord.java:48)
06-02 21:07:16.026: E/AndroidRuntime(4329):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
06-02 21:07:16.026: E/AndroidRuntime(4329):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
06-02 21:07:16.026: E/AndroidRuntime(4329):     ... 11 more
06-02 21:12:16.126: I/Process(4329): Sending signal. PID: 4329 SIG: 9

The funny thing is i copied the same exact Lookup method i used in another place which works just fine !, i even tried giving it a constant to look for which i know to exists just to check. but nothing. error over and over again !

Thanks !!!

Answer 1

A Cursor initially points to a record one before the start, to allow this kind of code:

final Cursor cursor = /* get cursor */;
while(cursor.moveToNext()) {
    /* do something with cursor */
}

If you are only expecting one record, and you are sure there will be one record, then before accesing your Cursor do:

cursor.moveToNext();

or:

cursor.moveToFirst();