View Full Version : How to discard initial data of QGraphicsView or QPainterPath's?
rajesh
13th August 2007, 15:14
I am displaying graph in a QGraphicsView using QPainterPath.
I am using QPainterPath's lineTo(x,y).
After displaying a huge data, I want to discard initial data(graph).
is there any way to discard initial(starting) data of QGraphicsView or QPainterPath's?
I am using Qt4.3.1 on windows.
marcel
13th August 2007, 15:24
If the root node of the graph is also the parent of all nodes( in the sense of QGraphicsItem parent-child relation) then you can call QGraphicsScene::removeItem.
It will remove the root and all children from the scene.
The responsibility to delete the item( deallocating the memory) is passed on to you.
rajesh
14th August 2007, 07:06
I dont want to remove full item, want to remove starting part of graph.
I am displaying digital wave signal by using QPainterPath. I want to display only 10ms data. when it cross 10 ms (say 11ms)data then I want to revove wave signal from begning(1ms data).
marcel
14th August 2007, 07:22
But that depends entirely on your data structure and graphics items design.
I can't give you a general method...
Regards
rajesh
14th August 2007, 07:56
m_pPainterPath.moveTo(0,0);
m_pPainterPath.lineTo(x,y);
m_pPainterPath.lineTo(x1,y1);
m_pPainterPath.lineTo(x2,y2);
after this can I delete like
m_pPainterPath.moveTo(0,0);
m_pPainterPath.removelineTo(x,y); --> is there any eqv function like removeline
Powered by vBulletin® Version 4.2.5 Copyright © 2024 vBulletin Solutions Inc. All rights reserved.