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<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>Hi All!<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>I’m trying to use custom forms for adding and editing
features within a layers.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>The forms that I’m creating need to query a PostgreSQL
database to populate controls. Using the UI init function seems like the thing
to do here. I’ve managed to populate the controls by setting up a new
connection and executing the query from within this init function.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>However these forms will be opened up all the time, and from
a database administrators point of view I would like cache the database
connection so a new connection is not created every time the form is opened. To
make things more complicated I would like to share this connection across
multiple feature forms within one QGIS user project. I also have a few other
functions relating to the admin of these layers that I currently have in a plug-in
which also needs the same database connection. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>Is there a way to do connection caching with all of this?
I thought about having a singleton class in my plug-in that stores this
connection, but it looks like I can’t access the plug-in registry from
the PyQGIS api </span></font><font size=2 face=Wingdings><span
style='font-size:10.0pt;font-family:Wingdings'>L</span></font><font size=2
face=Verdana><span style='font-size:10.0pt;font-family:Verdana'><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>Note I’m using psycopg2 for the database
connections.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>Thanks,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>Jeremy<o:p></o:p></span></font></p>
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