Update scene

mandruk1331

@mrjj I thought it will repaint the rects, because first I delete them and then I want to repaint them with new options

mrjj

Yes I guess it will repaint them on scene.
But it matters not for scene if you swap your own array.
The items still have same location as before as you do not setPos
(from code shown)

mandruk1331

@mrjj and another one, I have a loop inside of a loop and when the second one finishes its iteration it won't singleshot on another iteration of the first loop

for (int =0;i<10;i++){
//and when i is 1 the second loop won't singleshot again
for(int j=0;j<9;j++){
SingleShot
}
}

mrjj

well
Normally it works as many times as u set it up but hard to guess at with
only "SingleShot".

mandruk1331

@mrjj Why this code does not add the item, I don't understand, I remove it and then I want to re-add it with new options
void MainWindow::Shot(){
QGraphicsRectItem *t = new QGraphicsRectItem(rectan.at(0));

scene->removeItem(rectan.at(1));

rectan[1] = t;
scene->addItem(rectan[1]);
}

mrjj

@mandruk1331 said:

Why do yo u give rectan.at(0) to constructor ?
new QGraphicsRectItem(rectan.at(0));

Try
scene->addItem( new QGraphicsRectItem );
and tell if that not add a new item?

mandruk1331

@mrjj Ok, I managed to swap positions of the rectangles, but they swap not always, at first execution they swap on the other they don't, what could be the problem??

void MainWindow::Shot(){
QPointF Pos1;
QPointF Pos2;
Pos1 = rectan.at(5)->pos();
Pos2 = rectan.at(6)->pos();

rectan.at(6)->setBrush(Qt::blue);
rectan.at(5)->setBrush(Qt::green);
// rectan.at(5)->setBrush(Qt::blue);
rectan.at(6)->setPos(Pos1.rx()-30,Pos1.ry());
rectan.at(5)->setPos(Pos2.rx()+30,Pos2.ry());

}
Solved it)

mrjj

hi
put qDebug() << "in shot:"
in the
MainWindow::Shot()
to make sure its actually called mutiple times.

mandruk1331

@mrjj Pos2 = rectan.at(6)->scenePos(); - this one return (0,0), why? I tried pos() too

mrjj

if pos() returns 0,0 , it must mean the items is actually at 0,0.

mandruk1331

@mrjj and the other ones return 0,0. The object are unique they are all parents and have no child, I want to get the positions of each object so I could move them

mrjj

@mandruk1331
Something is not right.
Unless they are all really drawn at 0,0 then pos() should return the
actual position.
Did you new a QGraphicsRectItem and inserted directly in the list?

mandruk1331

@mrjj yes, and in the constructor I have set theirs poistions

mrjj

Ok, then they should still have the pos, unless you swapped with a
item having 0,0.

mrjj

Can I ask how any values (rects) you try to visualize?

mandruk1331

@mrjj 10

mrjj

@mandruk1331
ok.
And did you write the sort also?

mandruk1331

@mrjj yes
for( int i=0;i<random_numbers_.size()-1;i++){
for(int j=0;j<random_numbers_.size()-1;j++){

       if(random_numbers_[j]>random_numbers_[j+1]){
           count++;

QTimer::singleShot(1000*count, [=]{ MainWindow::Shot(j);});

        }
    }
}

mrjj

ok.
Don't really look like bubble sort.
:)

mrjj

Hi
I made a half assed bubble sort visualization using
widget painting.

2 things wrong with it.
The actual sort should rather be able to single step but instead
I use a delay function to slow down drawing. (not pretty)
So consider it concept rather than good practice.

That said, its meant for inspiration for your project.

https://www.dropbox.com/s/ob3x0uvdtbio942/bsort.zip?dl=0