Building a simple composite widget?

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I'm trying to build a set of reusable widgets.  Basically I have a bunch 
of places where I need the same dropdown boxes.  Each box may have a 
different selected value (Instance A uses Index 1 while Instance B uses 
Index 2), but the items in the list are the same.

I'm really just looking to build a set of Pre-populated "GtkComboBox" 
items - A simplified example is attached.

I'd prefer to store the possible enum values within a widget and then 
interrogate it rather than a bunch of "GtkListStore" items I need to 
edit over and over.

Is there a way I can convert the attached "ProtocolDropdown" object into 
a widget?  I'd want it to stay associated with the "Protocols" 
"GtkListStore".

Building a C program to track this feels like massive overkill, but I 
don't see a way to "Export object as widget".

Pat


-- 
Pat Riehecky

Fermi National Accelerator Laboratory
www.fnal.gov
www.scientificlinux.org


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<?xml version="1.0" encoding="UTF-8"?>
<!-- Generated with glade 3.20.0 -->
<interface>
  <requires lib="gtk+" version="3.20"/>
  <object class="GtkListStore" id="Protocols">
    <columns>
      <!-- column-name Display -->
      <column type="gchararray"/>
      <!-- column-name URI -->
      <column type="gchararray"/>
    </columns>
    <data>
      <row>
        <col id="0" translatable="yes">Over the web</col>
        <col id="1">http://</col>
      </row>
      <row>
        <col id="0" translatable="yes">Use legacy</col>
        <col id="1">ftp://</col>
      </row>
    </data>
  </object>
  <object class="GtkWindow">
    <property name="can_focus">False</property>
    <child>
      <object class="GtkComboBox" id="ProtocolDropdown">
        <property name="visible">True</property>
        <property name="can_focus">False</property>
        <property name="model">Protocols</property>
        <child>
          <object class="GtkCellRendererText" id="ProtocolDropownMenu"/>
          <attributes>
            <attribute name="text">0</attribute>
          </attributes>
        </child>
      </object>
    </child>
  </object>
</interface>

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