Qtableview verticalheader show icon instead of numbers

advseo32

Hi, every body

i have Qtableview with Qsqlquerymodel,

i want to show an icon on each vertical header when the the selection is active in that header

should i sublcass QHeaderView class and implement neccessary function

after setting up vertical header

@setVerticalHeader(QHeaderView * header);@

or i can use another solution without subclassing QheaderView ???

i try to this way without subclassing

@ ui->tableView->verticalHeader()->model()->
setData(ui->tableView->verticalHeader()->model()->index(1,1),"**",Qt::DisplayRole) ;
@

but nothing is work correctly

andre

You should subclass either QSqlQueryModel or QIdentityProxyModel. There, you reimplement the headerData function to return the data you want to have appearing in your header. If you use the proxy, you use it between your current QSqlQueryModel and your QTableView, while if you use the QSqlQueryModel subclass you use that subclass instead of your current QSqlQueryModel. The role you are looking for is the DecorationRole.

advseo32

Yes! andre i know how i can use proxymodel between mymodel and myvie

thank's for guideing me

but the only problem now is

how i can get selection even inside HeaderData() function

her is my code @QVariant MytableModel::headerData(int section, Qt::Orientation orientation, int role) const
{
if( orientation == Qt::Vertical && role == Qt::DecorationRole)
// how i can know when the user select a row
// So, i will use condition like so
if(row.IsSelectedByUser) // this is my main idea
return QPixmap("imgs/arrow.png");

return QVariant();

}@

andre

Ah, well, that was something you did not specify in your question.
The simple answer is: you can not. The selection state is something that is not a property of the model, but of the view in the Qt model/view setup. So, your model knows nothing of the selection state.

To me, that is a reason to use a proxy model here, and give it a setter for a QItemSelectionModel. Then, set the item selection model from your view on your proxy model, and use the item selection model to find out if the current row is selected or not.

advseo32

this is waht you mean ??
for example my proxy model is : mytablemodel
myview is : tableView;

i will implement a setter in mytablemodel like so

@QItemSelectionModel SetSelectionModel(QItemSelectionModel *selection) ;@

then in main coeur return the selection

@QItemSelectionModel MytableModel::SetSelectionModel(QItemSelectionModel *selection)
{
return selection;
}
@

then get the selectionmdel from the tableView

@tableView->selectionModel() ;@

then
@mytablemdoel->SetSelectionModel(tableView->selectionModel() )@

plz check it out

andre

No, that's not what I mean. I mean:

@
class MyProxyModel: public QIdentityModel
{
public:
void setSelectionModel(QItemSelectionModel* selection)
{
m_selectionModel = selection;
}

QVariant headerData(int section, Qt::Orientation orientation, int role) const;

private:
QItemSelectionModel* m_selectionModel;
};

QVariant MyProxyModel::headerData(...)
{
if (m_selectionModel)
{
//use the selection model to figure out if the current row is selected
// if so, return your arrow icon for the decoration role
}

return QIdentityProxyModel::headerData(...);

}

//where you create the models and view stuff
MyProxyModel* proxy = new MyProxyModel(myTableView);
proxy->setSourceModel(mySqlModel);
myTableView->setModel(proxy);
proxy->setSelectionModel(myTableView->selectionModel());
@

advseo32

Yes, this what i write in code above

mytablemodel is my proxymodel :)

i don't write the code, i just want to check if it's the idea that you want

finally, thank's for quick answers, complet example :)

regards, abdeu

advseo32

i have implemented the functions but the programme crashed

her is my header file @#include <QSortFilterProxyModel>
#include <QItemSelectionModel>
class MytableModel : public QSortFilterProxyModel
{
public:
explicit MytableModel(QObject parent = 0);
QVariant headerData(int section, Qt::Orientation orientation, int role) const;
QVariant data(const QModelIndex &proxyIndex, int role) const;
void SetSelectionModel(QItemSelectionModel selection) ;
private:
QItemSelectionModel *m_selectionModel;

};
@

myfunction her :
@
void MytableModel::SetSelectionModel(QItemSelectionModel* selection)
{
m_selectionModel = selection ;
}
@

her is my main

@
// my main model venteModel
// my proxy model ProxyProduitModel
// my view listProduitTableView

ProxyProduitModel->SetSelectionModel(listProduitTableView->selectionModel());
venteModel->setQuery("select *from Produit");
ProxyProduitModel->setSourceModel(venteModel);
listProduitTableView->setModel(ProxyProduitModel);

@

andre

You'll have to do better than "it crashes". Fire up your debugger when that happens, and figure out what is going wrong from that.

advseo32

i'm not familiare with debugger but, i have try to figure out ,what's the problem, and i get the line where the problem is happned

this @
// Her i get the index(0,0) from proxymodel
QModelIndex index = this->index(0,0) ;
// then i have maked the test

if( orientation == Qt::Vertical)
     if( orientation == Qt::Vertical && Qt::DecorationRole )
      // her is the line , the programme crashes her

if(m_selectionModel->isRowSelected(index.row(),index)) ;
return QPixmap("imgs/arrow.png");@

advseo32

Now, the problem is in the index of selected row

i try to get then selected index in view like so, but isn't works
@proxyModel->sourceModel()->index(0,0) ;@
or @proxyModel->index(0,0) ;@

i want to know how i get the selected row index, to be able to use it in

@isRowSelected(int row, const QModelIndex & parent)
and
isSelected(const QModelIndex & index)
@

advseo32

Now, it's clear that some thing is wrong with index, but i can't figured out
where is the problem

her is my code @
if( orientation == Qt::Vertical)
{
if( role == Qt::DecorationRole )
{
QModelIndexList indexes = m_selectionModel->selection().indexes();
QModelIndex index = m_selectionModel->selection().indexes().at(0);
if(m_selectionModel->isSelected(index))
return QPixmap("imgs/arrow.png");
}
}@

SGaist

Hi,

indexes might be empty, you don't check that case

advseo32

i have checked is the list isempty or no but the same problem

@if( role == Qt::DecorationRole )
{
QModelIndexList IndexsList = m_selectionModel->selection().indexes();
if(!IndexsList.isEmpty())
{
QModelIndex index = m_selectionModel->selection().indexes().at(0);
if(m_selectionModel->isSelected(index))
return QPixmap("imgs/square.png");
}
}
}@

advseo32

this is another code but, unfortunately also not working
@if( role == Qt::DecorationRole )
{
//i have used debugger and, the app crashed when execute the line below
bool indexListOk = m_selectionModel->selection().indexes().isEmpty() ;
if(!indexListOk)
{
QModelIndex index = m_selectionModel->selection().indexes().at(0);
if(m_selectionModel->isSelected(index))
return QPixmap("imgs/square.png");

}@

SGaist

Did you set m_selectionModel to something valid ?

If you follow the code from Andre carefully, you'll see that it checks first whether m_selectionModel is not NULL. Which also means that you must set it to NULL in your constructor.

advseo32

Oh! , i forgot to do this , thank's SGaist, andre, i will try to implement this
:)

SGaist

Always initializes all your pointers in the constructor either to something valid or NULL like in this case.

And check for NULL for all pointer variables that are initialized to NULL each time you'll be using these variables

advseo32

Yes, the probem caused by non initialisation of m_selectionModel pointer

but still i have a small a problem

when i select a row the icon show up, but when i leave the row (i can't get the icon disappear
@if(m_selectionModel)
{
QModelIndexList indexList = m_selectionModel->selection().indexes();
if(!indexList.isEmpty())
{
QModelIndex index = indexList.at(0);
if(index.isValid() )
return QPixmap("imgs/arrow.png");
}else{
return QSortFilterProxyModel::headerData(section,Qt::Vertical,Qt::DecorationRole);

            }

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

@

JKSH

@Andre: The headerDataChanged() signal doesn't get emitted with this method, correct? Thus the view won't be notified to update the headers when it's meant to?

[quote author="advseo32" date="1375459821"]i'm not familiare with debugger[/quote]Take time to learn. It's a very valuable tool for programmers: http://qt-project.org/doc/qtcreator-2.8/creator-debugging.html