Remove items selected from scene in a dynamic array

[AlvaroS]

@mrjj When I do for structure I save the line in the scene and in the lines_vector in the same iterator.
So the line in 4 position in scene is the same position than the line in 4 position in lines_vector.
So when I select for example one line in the scene, for example line 4, I have just to remove the line in position 4 in lines_vector.
So is ther any way to get the position vector of line that user selected in the scene

[mrjj]

• in the same iterator.
  Iterator is a helper class. Do you mean same index?
  So first line and first struc_line but is at [0] in both lists?

• So is ther any way to get the position vector of line that user selected in the scene
  The list contains one or more selected items.
  Its not in the order it was inserted. Just the order selected.
  So I dont think u can make a 1:1 map this way using selectedItems.

[AlvaroS]

@mrjj Yes, index sorry.
Okey so I can not do like that.

I have tried to use QMap like:

QMap<QGraphicsLineItem *, struc_line> LinesMap;

//Adding lines to the scene and lines_vector
for (int i=0; i<num_lines;i++)
                   line = scene->addLine(...)
                   LinesMap[line]=lines_vector[i];

//Button to remove lines selected

 QGraphicsLineItem *found= LinesMap.value(ui->scene->selectedItems(), NULL);

But it does not compile because there is a problem if users select more than one item because scene->selectedItems is a list

[mrjj]

yes
you must loop over list and check each

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

for (int c=0; c < selListt.size(); c++) {
QGraphicsLineItem *found= LinesMap.value(selList[c], NULL);
if (found) .....
}

[AlvaroS]

@mrjj Okey and there I remove item of QMap but how can I remove item of lines_vector?
Or you mean that I have to use QMap instead of std::vector?

[mrjj]

@AlvaroS
yes, your vector should be replaced with map.

[AlvaroS]

@mrjj I have tried to use QMap like you said but I get an error here:

error: no matching function for call to 'QMap<QGraphicsLineItem*, struc_line>::key(QGraphicsItem*&)'
QGraphicsLineItem *found=LinesMap.key(selList[c],NULL);
^

You know why?

Thanks a lot again

[mrjj]

yes,we store QGraphicsLineItem * in map and selectedItems is QGraphicsItem *

If you only do select "lines" then u can store it as QGraphicsItem * instead and
then no need for casting etc.

[AlvaroS]

@mrjj Perfect! It solved using std::map!!!! Thanks a lot

[mrjj]

super:)
good work.
please mark as solved.