check populating results window

[mfrasca]

in view.py we have this comment …

            # don't bother with a task if the results are small,
            # this keeps the screen from flickering when the main
            # window is set to a busy state

then follows a test on len(results) and I could not immediately see whether we do what we say, or the precise opposite.

I'm afraid this falls in the fibra cases #133, which I still think we should remove. I also have the impression that this fibra loop is freezing the interface in 3.1, when you do two large searches in fast sequence.

[mfrasca]

I've removed the fibra generator for this case, and replaced it with a Thread. structure of the Thread, so that it respects object ownership:

• constructing the thread, we receive objects belonging to the main (GUI) thread,
• the following three steps we do in a idle_add call
  • constructor runs in the GUI thread,
  • retrieve fields needed to work in the new thread,
  • start the new thread,
• in the non-GUI thread, use the fields, but leave the database objects alone,
• when done, call idle_add to do non-blocking GUI and database operations.