QPainter -draw a diagram and get data from it
for my project i need draw a diagram from model, and allow the user to edit it.
Here is an example:
Rectangles will be read from model so user won't be able to add them. Circles mean input and outputs for tasks (probably also will be read from model )
And what i need is to let user to add/delete an arrow from one circle to another and to get information about all connections in a list:
circle1- circle 2
circle 2- circle 4
This is possible to be done with QPainter?
if yes, can you provide me with some tutorials especially the part with user drawing and getting data from image?
andre last edited by
I would use the "Graphics View Framework":/doc/qt-4.8/graphicsview.html classes. You will use [[doc:QGraphicsView]] and it's friends [[doc:QGraphicsScene]] and [[doc:QGraphicsItem]] (and subclasses).
amban last edited by
This example will be the best to start with - http://doc.qt.nokia.com/4.7-snapshot/graphicsview-diagramscene.html
Hmm... previous developer tried to implement something like this, but he didn't succeed.
Now i have a piece of code that looks like that tutorial and i think I'll come back with more specific question.
Andre, amban thanks a lot for your help :)
Hello, i came back with other question:
I've managed to draw the rectangle with inputs:
Now i'm interested if i can figure out which circle was clicked.
DerManu last edited by
A circle is clicked if the distance of the click position to the center of the circle is smaller (or equal) to the radius of the circle, e.g.
@(click.x-circle.x)^2 + (click.y-circle.y)^2 <= circle.radius^2@
But if I'm not mistaken, the GraphicsView-Framework should already contain a simple circle/ellipse item with hit-test etc.
I think it have mouse click event, but the problem is that is one custom item,
that contains a rectangle and 2 circles(not three different objects).
It's a object with boundingRect = (0,0,100,100)
rectangle drawn at (0,25,100,50)
and another 2 circles. I can save that circle's QRect in a list, but how to get pointer position inside the graphics item?