qgraphicsscene remove item but sometime still in view

choujayylyxm

I use a qgraphicsscene additem a QChart and some inhert from the QChart item.I change QChart axisX and axisY range,and removeitem those items,then add new item.But sometime removeitem not working,item still in view.I cannot move it now.
And also call all of items prepareGeometryChange,not work.
So,why?

I test long time,found the point is set range.if resize the view,the removed item disappear.

Qt 5.9.5 kits

choujayylyxm

someone metion :https://www.qtcentre.org/threads/28749-Qt-4-6-GraphicsView-items-remove-problem

choujayylyxm

This post is deleted!

SGaist

Hi,

@choujayylyxm said in qgraphicsscene remove item but sometime still in view:

No one reply?!

No need to resort to bold fonts and such questions. A friendly ping is welcome though. This is a voluntary driven forum. People answering here do it on their own time and might not live in the same timezone as you. And it's also possible that no one has an answer for you.

In any case, you should provide a minimal compilable example that reproduces your issue.
You should also test your code against a more recent version of Qt, 5.9.5 is more than outdated. Qt 5.15 is the current LTS. Providing the platform your code runs on would also be good idea.

choujayylyxm

Ok，I understood.Sorry for that.
Here is a simple example:

   //click a button to switch line and run below code
  //  a QGraphicsView scene()->addItem(m_chart);
  //replace a new line
  QLineSeries * tmp = static_cast<QLineSeries *>(m_chart->series()[0]);
  QList<QPointF> dataPointList;
  //set new axis range
  m_chart->axisX()->setRange(0,dataVec[dataVec.size()-1].x());
  m_chart->axisY()->setRange(-qAbs(yMax)*1.2f, qAbs(yMax)*1.2f);
  tmp->replace(dataPointList);
  
  
  //delete last line a flag(circle)item in the qchart ，m_calloutsList is keep flags list
  for(auto& item : m_calloutsList[nDataIndex])
  {
      //item.prepareGeomtryChange //try it not work
      scene()->removeItem(item);
  }
  //add current line flag item
  for(auto& item2 : m_calloutsList[nDataIndex])
  {
  //item2.prepareGeomtryChange //try it not work
      scene()->addItem(item2);
  }

SGaist

Please provide a minimal compilable example that shows the behavior.

choujayylyxm

@SGaist OK,I upload a minimal compilable example for github
github link

Is it okay? It base on qt example callout

choujayylyxm

@SGaist Fine,I keep working on it.

SGaist

Did you try to call hide on your items before removing them from the scene ?

One thing: there's no need to make the QGraphicsItemObject. A simple QGraphicsRectItem is enough for your purpose.

Ketan__Patel__0011

try to After

remove the item from your qgraphicsscene

        scene()->removeItem(YOURITEM_OBJECT);
        ui->graphicsview->viewport()->update();
        ui->graphicsview->update();
        ui->graphicsview->show();