No Icons in TreeView

pracedru

Hi everybody

I'm trying to make a my own model to be used in a treeview and i'd like to have icons on my items.
in my model i've implemented the data function as

@
QVariant PipeDesignItemModel::data(const QModelIndex &index, int role) const
{

if (!index.isValid())
    return QVariant();

if (role != Qt::DisplayRole)
    return QVariant();

QObject * Item ;

Item = static_cast<QObject*>(index.internalPointer());

QVariant retObj;
QString iconfile = "c:/GreenPipe.ico";
QIcon icon = QIcon(iconfile);
qDebug() << icon.isNull() ;
if (role == Qt::DecorationRole)
    retObj.setValue( QIcon(iconfile));
retObj.setValue(Item->objectName());


return retObj;

}
@

However the role is never Qt::DecorationRole so the icon is never shown. What do i have to do to change the role?

giesbert

This role never reaches your if:

@
QVariant PipeDesignItemModel::data(const QModelIndex &index, int role) const
{

if (!index.isValid())
    return QVariant();

if (role != Qt::DisplayRole) // here you return if item role is decoration :-)
    return QVariant();

// ....

if (role == Qt::DecorationRole)
    retObj.setValue( QIcon(iconfile));
retObj.setValue(Item->objectName());


return retObj;

}
@

pracedru

Whoops.

You don't want to know how much time i've used at this.
thanx.

pracedru

I fixed it and the icon now shows. But not the text.

@
QVariant PipeDesignItemModel::data(const QModelIndex &index, int role) const
{

if (!index.isValid())
    return QVariant();
if (index.column()==1 && role != Qt::DisplayRole)
    return QVariant();
if (index.column()==0 && role != Qt::DecorationRole)
    return QVariant();
QObject * Item ;

Item = static_cast<QObject*>(index.internalPointer());

QVariant retObj;    

retObj.setValue(Item->objectName());

if (role == Qt::DecorationRole)
    retObj.setValue(greenPipe);

return retObj;

}
@

Can i show an icon and text at the same time?

giesbert

you are showing them in different columns.
what is your view?
typically, the roles are used in the same column:

@
QVariant PipeDesignItemModel::data(const QModelIndex &index, int role) const
{
if (!index.isValid())
return QVariant();

QObject* Item = static_cast<QObject*>(index.internalPointer());

QVariant retObj;   
switch(role)
{
case Qt::DisplayRole:
    retObj.setValue(Item->objectName());
    break;
case Qt::DecorationRole:
    retObj.setValue(greenPipe);
    break;
}

return retObj;

}@

this would show icon and text in each column. if you want to seperate by column, do it aditionally...

pracedru

Oh, i thought QVariant could hold more than one valuetype and that all the types needed would have to be returned. But i understand now that data is called for every role.

Thanks.

goetz

The icon is not in a separate column. So you have the text and the icon in column 0 (and probably more texts in more columns).

MisteKiste

Can somebody tell me how to resize the icon? I don't get it...