Re: Treeview with editable checkboxes besides items?

[Jef Driesen <jefdriesen hotmail com>]

Milosz Derezynski wrote:
> That's not really how this works. Instead:
>
> - You associate the renderer with an e.g. boolean column:
> column->add_property (*cell, "active",
> your_column_record_instance.bool_col);
> - You connect to the toggled() signal: cell->signal_toggled().connect
> (sigc::mem_fun (*this, &YourClass::callback_toggled))
> - In the handler you do something like:
>
> void
> callback_toggled (Glib::ustring const& string_path)
> {
>   TreeIter iter = your_model->get_iter (string_path);
>   (*iter)[your_column_instance.bool_col] = !bool
> ((*iter)[your_column_instance.bool_col]));
> }

This approach works fine. Thanks!

There is one minor issue now. Clicking the name (not the checkbox!) also 
toggles the checkbox. This is annoying if the user only wants to change 
the selection. Is there a way to prevent this? Changing the name works 
more intuitive: the first click changes the selection and editing starts 
with another click.

> Because, really, a cell renderer is in the first place only there to
> represent data.
>
> Having a "togglebutton cellrenderer" might be confusing at first because it
> seems to imply that now the view can handle model data by itself, but in
> fact for TreeView the model is read only.
>
> Even in an "editing-done" callback for a CellRendererText, you are only
> being supplied with the new text, and are still responsible for effectively
> updating the model yourself (in the most simple case, analogous to the above
> code, set the new text into the model column the relevant cell is
> displaying).

I still don't understand why I need to update the model myself with a 
CellRendererToggle. Because for a CellRendererText, all I need is:

renderer->property_editable() = true;

and editing works automatically. I would think that 
"property_activatable" does exactly the same thing for 
CellRendererToggle. But it doesn't seem to do that (or even anything at 
all). Because if I update the model myself from the signal handler, the 
value of "property_activatable" does not matter anymore. So what is it 
supposed to do?