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How to draw many items in scene

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obad

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  • "obad" started this thread

Posts: 49

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1

Thursday, July 29th 2010, 3:47pm

How to draw many items in scene

Hi,
I draw line on defined scene but when I want to draw item should I write this line
for example to draw two line should I write that :


Source code

 
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QGraphicsLineItem *line1 = new QGraphicsLineItem(0,&scene)
p, li { white-space: pre-wrap;  line1->setLine(0.0,0.0,10.0,10.0);
QGraphicsLineItem *line2 = new QGraphicsLineItem(0,&scene);
line2->setLine(0.0,0.0,10.0,10.0);
How can avoid this? I need to draw may lines without repeate that line

Sifaka

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2

Thursday, July 29th 2010, 10:14pm

Could you use a loop?
For example:

for (int i = 0; i < theNumberOfLinesYouWant; i++)
{
QGraphicsLineItem *line = new QGraphicsLineItem(0, &scene);
line->setLine(0.0, 0.0, 10.0, 10.0);
}

obad

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3

Friday, July 30th 2010, 11:20am

I know loop but I mean is there any another way for line definition of line for example in QPainter

QPainter line;
line.drawline(.......); // first line
line.drawLine (......); // second line
.
.
.

Sifaka

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4

Friday, July 30th 2010, 2:21pm

Oh, okay.
QGraphicsScene has a functions addLine(), so you could write

scene->addLine(0.0, 0.0, 10.0, 10.0);
http://doc.trolltech.com/4.5/qgraphicsscene.html#addLine


Hope this helps!

obad

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5

Friday, July 30th 2010, 2:49pm

that is good , but i will find problem when I want to change the item coordinate because the line will be drawn on the scene coordinate
i need in the QGraphicsItem terms

obad

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6

Friday, July 30th 2010, 7:45pm

I got it , Thanks for every one here