How do I reconstruct columns dynamically on GtkTreeView

ayanami · March 25, 2010, 11:42pm

Any idea? thanks in advance

ayanami · March 26, 2010, 9:07am

2010/3/25 Javier M. [email protected]:

Any idea? thanks in advance

Could you be more precise ? I don’t get what you want to do.

Simon

ayanami · March 26, 2010, 5:55pm

Sorry. My intention is to show the data from tables of database, that
the user can select. Therefore, a priori, I don’t know either the number
or type of the columns that I must show. The Question is how I can
dynamically create the ListStore.new, Now better?
Very grateful

ayanami · April 8, 2010, 11:41am

2010/3/26 Javier M. [email protected]:

Sorry. My intention is to show the data from tables of database, that
the user can select. Therefore, a priori, I don’t know either the number
or type of the columns that I must show. The Question is how I can
dynamically create the ListStore.new, Now better?

Considering the pseudo table

User
id integer
name string
birth date

If you can get the type of columns, try to make a switch.

model_types = Array.new
table_attributes_type.each do |attribute_type|
case attribute_type
when ‘tinyint’, ‘integer’, ‘longint’
model_types << Numeric
when ‘varchar’, ‘text’
model_types << String
[…]
end
my_list_store = ListStore.new(model_types)

If you can’t have the types, you might put everything as string, and
do the conversion on the fly.
Calling ‘to_s’ when filling the model
Calling ‘to_i’, ‘to_f’, Date.parse, etc when reading from the model.

so the model would :
my_list_store = ListStore.new([String] * number_of _attributes)

Makes sense ?

Simon

ayanami · April 8, 2010, 12:58pm

Hei Simon,

you can find my approach here →

github.com

bolthar/freightrain/blob/master/lib/extensions/gtk/widgets/gtk_treeview.rb


module Gtk

  class TreeView

    def create_column(column_definition)
      renderer   = Gtk::CellRendererText.new
      title      = column_definition.keys.first
      attributes = {}
      column_definition.values.first.each do |binding|
        attributes[binding["property"]] = @paths[binding["path"]]
      end
      column     = Gtk::TreeViewColumn.new(title, renderer, attributes)
      self.append_column column
    end

    def bind(options)
      if options[:property].to_sym == :elements
        options[:force] = true
        columns = normalize_column_bindings(options[:columns])

This file has been truncated. show original

In short: i store the reference to the object in the first column, every
other field i want to display will be a string, so the ListStore.new
call looks something like:

ListStore.new([Object, [String] * no_of_fields_to_display].flatten)

On callbacks i do every operation on the object, the fields are just for
display. I don’t know if this is suitable to your case.

Bye!

–
Andrea D.

ayanami · April 8, 2010, 1:33pm

2010/4/8 Andrea D. [email protected]:

On callbacks i do every operation on the object, the fields are just for
display. I don’t know if this is suitable to your case.

It’s not my case, I’m just answering Javier :).

Thanks anyway.

I will have to take a look at freightrain, I’m mostly doing everything
by hand right now.
It would be nice to have a higher level lib, MVC style.
I don’t have much time though, unfortunately.

Simon

ayanami · April 8, 2010, 1:49pm

Oh, I am sorry I am very new to the mailing list, i guess the
original message was posted before i joined.

There’s no documentation for freightrain at the moment so I am aware
that it’s kind of difficult to understand how to use it. I am working on
that though, i hope i can put up a website with all needed to learn it
in a month or so. Thanks for the interest anyway!

Bye!

–
Andrea D.