I was tried to display real-time data in my mapcanvas. In my mapcanvas, i have 4 layer, but i juz want to refresh 1 layer only(this layer retrieve data from PostGis) from the mapcanvas without refreshing all layer in the mapcanvas. I already searching from this forum and Google it, and the result is i should use QgsMapCanvasItem that have that capabilities to rendering single layer without refreshing mapcanvas. But, i don't know how to implement it in my application. I'm using sample application from Mr.Tim Sutton, it is a great tutorial for a beginner like me, and i think its better to include the code in here. This is what i already done:
from my reading,what i understand is i should use QgsMapCanvasItem::updatePosition() to make my mapcanvas look like real-time. Is it true? And i really hope you guys can teach me about how to implement it in my code.