On account.voucher I added a one2many field like this :
'bls_to_pay': fields.one2many('stock.picking.out','bl_id','BLS to pay'),
I added a many2one field on both stock.picking.out and stock.picking like this :
'bl_id': fields.many2one('account.voucher','BLs to pay'),
On stock.picking.out, I have a field "num_bl", that I added by inheritance. and so as to add a field into stock.picking.out, you have also to add it on stock.picking as well, and that's what I did.
The probleme is when I try to display the field on the one2many tree, it prints on log the following error :
Can't find field num_bl on the following view parts composing the view of object model account.voucher, either you wrongly customzed the view, or some modules bringing those views are not compatible with your current data model.
All of this knowing that I tried with other fields of stock.picking, wich have been created initially with the model, and not added by inheritance and it worked, the problem is just with the field "num_bl", wich have been added by inheritance ( custome module ).
Here is an example, working for date field of stock.picking : http://prntscr.com/5euiix
Why this behaviour occurs ?
The error message indicates that you tried to create a view for account.voucher model that contains num_bl field. As you have stated this field is in the stock.picking. Maybe you can post your view here so that it can be analyzed further.
Also you might want to post the definition of num_bl field as well complete with the class.