Unable to pass QModelIndex to a function due to some C++ constrait

scotryder

Hi there,

I have override filterAcceptRow but unable to pass index0 to a custom function and get the following error

error: reference to type 'const QModelIndex' could not bind to an rvalue of type 'const QModelIndex *' CanBeFilter(&index0, &canReturn);

Here is my code so far

bool FilterProxyModel::filterAcceptsRow(int sourceRow, const QModelIndex &sourceParent) const
{



     const QModelIndex index0 = sourceModel()->index(sourceRow, 0, sourceParent);


     
     bool canReturn = true;
 
 
 
     CanBeFilter(&index0, &canReturn);

     return canReturn;

}

//CanBeFilter Signature is
void FilterProxyModel::CanBeFilter(QModelIndex &index, bool &canReturn) const

I know its a C++ issue but im unable to solve it.

Thanks

Taz742

@scotryder
Because index0 is const and in your function

void FilterProxyModel::CanBeFilter(QModelIndex &index, bool &canReturn) {
    //index is reference index0 and index is not const.
    //const QModelIndex index0; It means that it should not change. But in this function you give it the right to change it.
}

You can add const QModelIndex &index or remove 'const' 'QModelIndex index0'.

http://www.learncpp.com/cpp-tutorial/73-passing-arguments-by-reference/

jsulm

@scotryder said in Unable to pass QModelIndex to a function due to some C++ constrait:

CanBeFilter(&index0, &canReturn);

You're trying to pass pointers where references are expected. Change it to:

CanBeFilter(index0, canReturn);

And as @Taz742 pointed out make first parameter const.
In addition CanBeFilter should return the result instead of modifying a parameter:

bool FilterProxyModel::CanBeFilter(const QModelIndex &index) const;

bool canReturn = CanBeFilter(index0);