Qtableview verticalheader show icon instead of numbers

[andre]

In your constructor, you first set m_selectionModel to 0, meaning that it does not refer to a valid object. And on the next line, you try to connect to it anyway? You should make the connection from your SetSelectionModel method where you actually have the valid object, at line 92 of your cpp.

Note that because you are not changing the stucture or sort order of your model, it is more efficient to use QIdentityProxyModel than QSortFilterProxyModel as your base class.

[advseo32]

unfortunately, i can't get this work

i don't know where i'm wrong @void MytableModel::SetSelectionModel(QItemSelectionModel *selection)
{
m_selectionModel = selection ;
QObject::connect(m_selectionModel,SIGNAL(currentRowChanged(QModelIndex,QModelIndex)),
this,SLOT(emitHeaderDataChanged(QModelIndex&,QModelIndex&))) ;
}

void MytableModel::emitHeaderDataChanged(QModelIndex &current, QModelIndex &prev)
{
int currentRow = current.row();
int previousRow = prev.row() ;
emit headerDataChanged(Qt::Vertical,currentRow,previousRow);

}
@

[andre]

• Why do you use QObject:: before your connect?

• What does this call return?

• Do you see any application output for this connect statement?

• Where do you call SetSelectionModel? And how?

• What exactly does not work?

• Does emitHeaderDataChanged get called or not?

[advseo32]

Why do you use QObject:: before your connect?

i forgot that the macro Q_OBJECT is included

What does this call return?

what function you mean, connect ??

Do you see any application output for this connect statement?

no

Where do you call SetSelectionModel?

i  call it in other file , where is use my view( to get selection model)

And how?

with @myMytableModel->SetSelectionModel(myView->selectionModel());@

What exactly does not work?

when the icon ( arrow.png) showed in vertical and the selection changed  the icon stay in vertical header and never disappear

witch mean, all rows have an icon "arrow.png" in their left side ( vertical header) in stead of only the selected one !!

Does emitHeaderDataChanged get called or not?

i place break point in it but it's not called

[andre]

I see something weird in your headerData implementation:

What you do there, is that you only check if there are selected indices. You are not checking if any of the selected indices is on the row that the current header data is requested for. So indeed: as long as you have a selected item, it should make all your vertical headers render the arrow.

I do not get why you don't get the signal. Did you try with the selectionChanged signal from QItemSelectionModel?

[advseo32]

i have modified the code , but i get an error

@Démarrage de E:\apprendreQt\build-gestionstock5-Desktop_Qt_5_1_0_MinGW_32bit-Debug\debug\gestionstock5.exe...ASSERT failure in QList<T>::at: "index out of range", file C:\Qt\Qt5.1.0\5.1.0\mingw48_32\include/QtCore/qlist.h, line 452
Invalid parameter passed to C runtime function.
Invalid parameter passed to C runtime function.

@
i have checked with debugger to get the source of the error , it crashed
when he execute this line

@QModelIndex index = indexList.at(0);@ ( line 9 )

her is headerData for vertical header @case Qt::Vertical :
switch (role) {
case Qt::DecorationRole :
if(m_selectionModel)
{
QModelIndexList indexList = m_selectionModel->selection().indexes();
if(!indexList.isEmpty())
{
QModelIndex index = indexList.at(0);
if(index.isValid() )
{

                    if(index.row() == section)
                        return  QPixmap("imgs/arrow.png");
                    else
                        return "**";

                }

            }else
                return QIdentityProxyModel::headerData(section,Qt::Vertical,Qt::DecorationRole);
        }else
            return QIdentityProxyModel::headerData(section,Qt::Vertical,Qt::DecorationRole);

        break;
    default:
        return QIdentityProxyModel::headerData(section,orientation,role);
        break;
    }
    break;@

i have changed my signal to selectionChanged()
@void MytableModel::SetSelectionModel(QItemSelectionModel *selection)
{
m_selectionModel = selection ;
connect(m_selectionModel,SIGNAL(selectionChanged(QItemSelection,QItemSelection)),this,SLOT(emitHeaderDataChanged(QItemSelection,QItemSelection))) ;
}
@

and her is my slot ( the program enter into slot )

@void MytableModel::emitHeaderDataChanged(QItemSelection selected, QItemSelection deselected)
{
int selectedRow = selected.indexes().at(0).row() ;
int deselectedRow = deselected.indexes().at(0).isValid() ? deselected.indexes().at(0).row() : 0 ;

emit headerDataChanged(Qt::Vertical,selectedRow,deselectedRow);

}
@

[SGaist]

your indexList is empty and you are trying to access an element

[andre]

[quote author="SGaist" date="1375786256"]your indexList is empty and you are trying to access an element[/quote]

No, as there is a check for that just two lines above...

[advseo32]

[quote author="SGaist" date="1375786256"]your indexList is empty and you are trying to access an element[/quote]
i think there is a problem with connect methode

@void MytableModel::SetSelectionModel(QItemSelectionModel *selection)
{
m_selectionModel = selection ;
connect(m_selectionModel,SIGNAL(selectionChanged(QItemSelection,QItemSelection)),this,SLOT(emitHeaderDataChanged(QItemSelection,QItemSelection))) ;
}@

and SLOT

@void MytableModel::emitHeaderDataChanged(QItemSelection selected, QItemSelection deselected)
{
int selectedRow = selected.indexes().at(0).row() ;
int deselectedRow = deselected.indexes().at(0).isValid() ? deselected.indexes().at(0).row() : 0 ;

emit headerDataChanged(Qt::Vertical,selectedRow,deselectedRow);

}
@

when i delete this line @connect(m_selectionModel,SIGNAL(selectionChanged(QItemSelection,QItemSelection)),this,SLOT(emitHeaderDataChanged(QItemSelection,QItemSelection))) ;@
from setSelectionModel(), it works perfectly :), without emitting headerDataChanged() signal

i wish to figure out what happened

[SGaist]

[quote author="Andre" date="1375786790"]
[quote author="SGaist" date="1375786256"]your indexList is empty and you are trying to access an element[/quote]

No, as there is a check for that just two lines above...[/quote]

Indeed, keyboard/brain/finger bug, I was thinking about selected/deselected.indexes() which may be empty

[advseo32]

[quote author="SGaist" date="1375787169"]
[quote author="Andre" date="1375786790"]
[quote author="SGaist" date="1375786256"]your indexList is empty and you are trying to access an element[/quote]

No, as there is a check for that just two lines above...[/quote]

Indeed, keyboard/brain/finger bug, I was thinking about selected/deselected.indexes() which may be empty[/quote]

Probably, because there is no selected row in my view at intial, so deseleted.indexs() is empty !

sorry, if you get a difficulty to understand me ( English is not my native language)