[Glade-users] Building a simple composite widget?

[juanpablougarte at gmail.com (Juan Pablo Ugarte)]

On Tue, 2018-02-20 at 16:03 -0600, Pat Riehecky wrote:
> 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".

First of all you have to make your custom GtkComboBox derived class

https://developer.gnome.org/gtk3/stable/GtkWidget.html#composite-templa
tes

(In Glade check the composite checkbox next to widget ID to make that
toplevel a composite template)

Then you will need to write a custom catalog for Glade to know about
your new widget

https://developer.gnome.org/gladeui/3.20/catalogintro.html

AS the first implementation you do not need to load your library in
Glade you can simply define your new class and add parent="GtkComboBox"

Something like...

<?xml version="1.0" encoding="UTF-8"?>
<glade-catalog name="custom"
               depends="gtk+">

  <glade-widget-classes>
    <glade-widget-class name="MyComboBox"
                        generic-name="mycombobox"
                        title="MyComboBox"
                        parent="GtkComboBox"/>
  </glade-widget-classes>
  
  <glade-widget-group name="custom" title="Custom Widgets">
    <glade-widget-class-ref name="MyComboBox"/>
  </glade-widget-group>

</glade-catalog>

should do the trick after you save the catalog in a place specified in
Glade->preferences->Extra catalog paths

hope this helps

JP