1 Reply Latest reply on Sep 19, 2006 3:21 AM by raghunathrao

    ComboBox null object reference error bug

    Malcolm Edgar
      Hi All,

      I am getting the following error when using a ComboBox's defined as:

      <mx:ComboBox id="gicsCodeInput"
      text="{ModelLocator.getInstance().arsGroupMember.gicsCode}"
      dataProvider="{ModelLocator.getInstance().gicsCodes}"/>

      The dataProvider is providing an ArrayCollection of String values where the first value is a blank string "". There is a StringValidator associated with the ComboBox to make sure the user makes a selection.

      The error occurs when you tab to the ComboBox, and then use the down arrow key on the keyboard. This error does not occur when you use the mouse to access the drop down list. In the debugger the _downdown property is null.

      TypeError: Error #1009: Cannot access a property or method of a null object reference.
      at mx.controls::ComboBox/mx.controls:ComboBox::keyDownHandler()[C:\dev\GMC\sdk\frameworks\mx \controls\ComboBox.as:1848]

      In the ComboBox.as the following line is raising an null object reference error as the _dropdown property is null:

      1847:
      1848: if (oldIndex != _dropdown.selectedIndex)
      1849: selectedIndex = _dropdown.selectedIndex;