title: Wrap GtkComboBox column-wise instead of row-wise
body: <p>I'm having trouble to wrap a GTKComboBox with a large number of alphabetically sorted entries column-wise instead of row-wise.</p>
  
  <p>Please have a look at the following minimal working example and the attached screenshot to get an idea of what I'm trying to achieve. The focal point of my code is the function <code>gtk_combo_box_set_wrap_width</code> which wraps the GtkComboBox as table (see <a href="https://developer.gnome.org/gtk3/3.22/GtkComboBox.html#gtk-combo-box-set-wrap-width" rel="nofollow noreferrer">GTK3 API reference</a>).</p>
  
  <pre><code>#include &lt;gtk/gtk.h&gt;
  
  int main(int argc, char *argv[]) 
  {
      GtkWidget *window;
      GtkWidget *combobox;
  
      gtk_init(&amp;argc,&amp;argv);
  
      window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
      gtk_container_set_border_width(GTK_CONTAINER(window), 10 );
      gtk_window_set_default_size(GTK_WINDOW(window), 100, 50);
  
      combobox = gtk_combo_box_text_new();
      gtk_combo_box_text_append(GTK_COMBO_BOX_TEXT(combobox), NULL, "A" );
      gtk_combo_box_text_append(GTK_COMBO_BOX_TEXT(combobox), NULL, "B" );
      gtk_combo_box_text_append(GTK_COMBO_BOX_TEXT(combobox), NULL, "C" );
      gtk_combo_box_text_append(GTK_COMBO_BOX_TEXT(combobox), NULL, "D" );
  
      gtk_combo_box_set_wrap_width (GTK_COMBO_BOX(combobox), 2);
  
      gtk_container_add(GTK_CONTAINER(window), combobox);
  
      gtk_widget_show_all(window);
      gtk_main();
  
      return(0);
  }
  </code></pre>
  
  <p>This gives me the following output:</p>
  
  <p><a href="https://i.stack.imgur.com/TCDEJ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/TCDEJ.png" alt="Row-wise wrap"></a></p>
  
  <p>As you can see, the entries get wrapped row-wise, i.e. are read from left to right.</p>
  
  <p>Is there a convenient way to wrap the elements column-wise <strong>without re-sorting them accordingly</strong>?</p>
  
  <p><a href="https://i.stack.imgur.com/1OTSS.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/1OTSS.png" alt="Column-wise wrap"></a> </p>