[Qgis-developer] Custom composer items?
ccrook at linz.govt.nz
Sun Feb 28 17:36:50 EST 2010
I'm wanting to add scale information for symbols to composer. These are arrow symbols representing vector fields, so I want to be able to show in the composer generated page what the scale of the arrows is (ie how long an arrow represents a 5cm offset at a point, or whatever).
Logically this would be a custom composer item, but I cannot see any way to create a custom item, either in C++ or in Python (my preference!), without modifying the base composer classe(s). Can anyone confirm this?
A slightly less desirable approach would be to draw the scale information onto the map item in composer. This would constrain the placement - it would be nicer to be able to place it arbitrarily as other widget items.
In the main Qgis window I draw this scale information onto the map canvas in response to the renderComplete signal, in the same way as the scale bar or north arrow, but I don't think there is an equivalent event when the composer map item is drawn? So I can't use that approach to draw onto the canvas...
I think I may be able to draw the scale information by adding a custom map layer.
Can anyone suggest better approaches, or point me to something obvious I've missed?
This message contains information, which is confidential and may be subject to legal privilege.
If you are not the intended recipient, you must not peruse, use, disseminate, distribute or copy this message.
If you have received this message in error, please notify us immediately (Phone 0800 665 463 or info at linz.govt.nz) and destroy the original message.
LINZ accepts no responsibility for changes to this email, or for any attachments, after its transmission from LINZ.
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the Qgis-developer