Question

I’m developing a webapp with Ruby 1.8.7 and Rails 2.3.5, which will manage some industrial process. One of the requirements is that, when someone wants to delete a registry, the delete task will have to make an update to one of the fields of the DB table. This field establishes if a record is active or not.

I have modified the default delete method generated by the scaffold:

def activar
  @alarma = Alarma.find(params[:id])

  respond_to do |format|
    if @alarma.update_attribute(:estado_id => 1)
      flash[:notice] = 'La alarma ha sido activada.'
      format.html { redirect_to(@alarma) }
      format.xml { head :ok }
    else
     format.html { render :action => "index" } 
     format.xml { render :xml => @alarmas }
    end
  end
end

def desactivar
  @alarma = Alarma.find(params[:id])

  respond_to do |format|
    if @alarma.update_attribute(:estado_id => 2)
      flash[:notice] = 'La alarma fue desactivada.'
      format.html { redirect_to(@alarma) }
      format.xml { head :ok }
    else
     format.html { render :action => "index" } 
     format.xml { render :xml => @alarmas }
    end
  end
end 

where :estado_id => 1 is active, and :estado_id => 2 is deactive. However, when a I try to do the update, it doesn’t change the attribute. Actually, it doesn’t do anything.

Does anyone have a clue?

Answer 1

You should use update_attributes in your case

update_attributes(attributes) public

Updates all the attributes from the
passed-in Hash and saves the record.
If the object is invalid, the saving
will fail and false will be returned.

example:

@user.update_attributes(:status => 'active')

or @alarma.update_attribute(:estado_id, 2) if you want to use update_attribute

update_attribute(name, value) public

Updates a single attribute and saves
the record without going through the
normal validation procedure.