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Message-ID: <e593da80510231500k117b0b55vc6325414a3608f79 at mail.gmail.com>
Date: Sun, 23 Oct 2005 23:00:42 +0100
From: Robert Schneck-McConnell <schneck at gmail.com>
To: lablgtk at math.nagoya-u.ac.jp
Subject: Threading issues, and custom tree models
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I've got a custom tree model up and running with LablGTK.  The trick
is to ensure the values stored in GtkTreeIters aren't in the minor
heap.  LablGTK already forbids heap compaction, I recently found out,
so those values aren't moving.

I still get occasional weird behavior which seems to be related to
threading issues.  I use basically
Thread.create (GtkThread.main ())
to set GTK going.  The real main thread of the program is messing with
the data structure which the custom tree model accesses with OCaml
callbacks.  I observe the following happen:

(1) The GTK thread is refreshing the display and calling the custom
model's get_value function to get the values in the columns of row r.
(2) Halfway through the columns, the main thread deletes (an ancestor
of) r, emits the GTK signal row_deleted, and moves on.
(3) The GTK thread continues getting the values of the columns of r,
which no longer exists.

It seems to me that I need to make all changes to the tree model's
data structure wait for GTK.  It almost looks like there are functions
in GtkThread to do this, but I don't quite understand.  Can anyone
explain?

Robert