Re: How to update the content of a tree view

[Andrew Potter <agpotter gmail com>]

On Sat, Feb 23, 2013 at 9:39 AM, John Tall <mjtallx gmail com> wrote:

However, every now and then the progress bars has to be updated and
this is where I don't follow. I don't get how I should do to properly
update the value of a specific row.

I would put a pointer to your job object in the TreeModel set up a 

Glib::signal_timeout. In the timeout, iterate through your treemodel and use 

iter->get_value(columns.job)->get_progress();

Be sure to disconnect the signal_timeout when there are no jobs in progress.

And you should only have one of these timeouts, even if you have several jobs

running.

Using signal_timeout for updating progress bars usually results in a much

smoother looking result--especially in this case, where you do have to iterate

through on average half the treemodel for each update. Its up to you to choose

a sensible period. 50 ms might be sensible for a job that completes in under a

minute. Using signal_timeout().connect_seconds() might be more reasonable if

you're sure it will take more than a minute.