Move item Line with Line Edit.

AlvaroS

Hi everyone.
First of all thanks for helping me.

I have some LineItems in a Scene represented by QGraphicsView.
I would like to add 4 LineEdit and one button.

The idea is the next:
the Line Edits are: right, left, up, down.
The button is: move lines.

If the user selects and item and put for example: 3 in right and 0 in the left, up and down. The line selected is moved 3 coordinates in X to the right.

I thought that I can do that If I can access to coordinates of selected items and then just add the number of user puts in LIneEdit.

but how can I access to that¿

I add lines with:

line = scene->addLine(x_start,y_start,x_end,y_end, red);

Thanks a lot!

Alvaro.sal

This post is deleted!

mrjj

hi
"but how can I access to that¿"

I assume you mean the line?
If selected then u can get it via
http://doc.qt.io/qt-5/qgraphicsscene.html#selectedItems

Note: that you might need to make the item selecteable
http://doc.qt.io/qt-5/qgraphicsitem.html#setFlags
QGraphicsItem::ItemIsSelectable

AlvaroS

@mrjj Thanks for answering.

Yes, the line selected or lines selected.
But I need the coordinates of the line (x_start, y_start, x_end,y_end)
I did this:

QList<QGraphicsItem*>a;
    a = scene->selectedItems();

    int num_item_selected;
    num_item_selected = a.size(); //Num of items selected.

    for (int i=0; i<num_item_selected; i++)
    {
        QRectF itemBR = a.value(i)->boundingRect();
        QPointF sceneBR = a.value(i)->scenePos();
        //std::cout << sceneBR << std::endl;
    }

but I can not get the coordinates...

mrjj

It seems fine
Did you read about
http://doc.qt.io/qt-5/graphicsview.html#the-graphics-view-coordinate-system

scenePos() is correct so you must be getting other values than
expected?

If you cast to an actual QGraphicsLineItem

QGraphicsLineItem * line=qobject_cast<QGraphicsLineItem * >(a.value(i));
if ( line ){
http://doc.qt.io/qt-5/qgraphicslineitem.html#line
}
Maybe those values are the ones you expect ?

AlvaroS

@mrjj Yes, the scenePost() retunr always 0,0 ... It does not matter what line I select, the value is always 0,0 ...

When I write your code it return me an error which is:

error: no matching function for call to 'qobject_cast(QGraphicsItem*)'
QGraphicsLineItem * linea =qobject_cast<QGraphicsLineItem * >(a.value(i));
^

        QGraphicsLineItem * linea =qobject_cast<QGraphicsLineItem * >(a.value(i));
        if (linea)
        {
            linea->line;
        }

mrjj

@AlvaroS said:
oh sorry
try with qgraphicsitem_cast

AlvaroS

@mrjj That works fine.
Thanks a lot!!!

mrjj

@AlvaroS
super. :)
If possible please mark as solved using the topic button.

Solved Move item Line with Line Edit.