Getting row item is dropped at on a qtwidgettable

tony67

Hi All,
I have two tables, I can copy items from the first to the second (a qtwidgettable) by dragging and dropping. This is working well. I've set up an event filter to detect when an item is dropped. However I'd like to know what row the item is dropped on and can't work this out. Can anyone explain how I can detect the row location of the drop please? My code below show's where I'd like to get the drop location.

    if( loc == ui->tableWidget->viewport() && event->type() == QEvent::Drop )
    {

        qDebug() << "dropped in the table but where!!!!";
    }

Thanks

mrjj

Hi
One way is to use the x,y location of the drop.
Then ask the Table what item is at that place.
https://forum.qt.io/topic/50495/solved-qtablewidget-drop-event-get-cell/4

tony67

Thanks for the reply, but I can't follow the answer :s. For example he get's position with

int position = event->pos();

but QEvent doesn't have anything called pos() ? I know it has type(), but where are they getting pos from?

Sorry I'm having real trouble even goggling this, maybe I'm using wrong terms due to my limited knowledge of QT

mrjj

@tony67
Ok. maybe first tell me what function we are in ?
The DropEvent has pos
http://doc.qt.io/qt-5/qdropevent.html#pos

You might need to cast the generic event to a DropEvent
DropEvent *de=qobject_cast<DropEvent *>(event);
if(de) {
...de->pos()-..
}

tony67

Thanks for helping. I've tried to use DropEvent, it says the class doesn't exist? Should I be using QDropEvent?
If I do that I get another error

QDropEvent *dropevent = qobject_cast< QDropEvent *>(event);

edit_dialog.cpp:107: error: invalid use of non-static member function
QDropEvent *dropevent = qobject_cast< QDropEvent *>(event);

mrjj

@tony67
Hi
Normally you would override the
void YourTable::dropEvent(QDropEvent *event)
virtual function.
http://doc.qt.io/qt-5/dnd.html

Not sure how u do it now. Is it an event filter?

tony67

yes using

ui->tableWidget->viewport()->installEventFilter( this );

then

bool Edit_Dialog::eventFilter( QObject* object, QEvent* event )
{
    if( object == ui->tableWidget->viewport() && event->type() == QEvent::Drop )
    {

I thought this was the correct way to do things from reading?

mrjj

@tony67
U can also use eventfilter but if you look at
http://doc.qt.io/qt-5/dnd.html
you see that normally you be using
QDragEnterEvent
Event which is sent to a widget when a drag and drop action enters it
QDragLeaveEvent
Event that is sent to a widget when a drag and drop action leaves it
QDragMoveEvent
Event which is sent while a drag and drop action is in progress
QDropEvent
Event which is sent when a drag and drop action is completed

which are all virtual functions where the Event is of the right type.

However, lets focus on eventfilter

if you
#include <QDropEvent>
and
QDropEvent *dropevent = qobject_cast< QDropEvent *>(event);

It still complains about the cast?
I might remember wrong.
Try
QDropEvent *dropevent = dynamic_cast< QDropEvent *>(event);

tony67

@mrjj said:

QDropEvent *dropevent = dynamic_cast< QDropEvent *>(event);

Thank's second method worked!

mrjj

@tony67
Super.
Sorry my bad. Been using qobject_cast too much :)