[ SOLVED ]Problem in getting mouseEvent on QTableWidget

M_31

I want to have mouse press event & mouse release event on QTableWidget

my code is

@
#include <QMouseEvent>
#include <QKeyEvent>
#include <QEvent>

CTestDlg::CTestDlg()
{
ui->setupUi(this);
ui->TableWidget->setSelectionMode( QAbstractItemView::ExtendedSelection );
ui->TableWidget->setMouseTracking( true );
ui->TableWidget->installEventFilter( this );
}
bool CTestDlg::eventFilter(QObject *object, QEvent *event)
{

if (event->type() == QEvent::MouseButtonPress )
{
    
    if (  object == ui->TableWidget )
    {
        qDebug()<<"MOUSE BUTTON PRESSED";         
        
    }
    return QObject::eventFilter(object, event);

}
else if (event->type() == QEvent::MouseButtonRelease )
{
    if ( object == ui->TableWidget )
    {
        qDebug()<<"MOUSE BUTTON PRESSED";         
     }
      return QObject::eventFilter(object, event);

}

return QObject::eventFilter(object, event);

}
@

while i click the tablewidget on my Dialog window , i am not at all getting any output as either "MOUSE BUTTON PRESSED" or "MOUSE BUTTON RELESED"....please let me know...whether i am missing anything on my code...

andre

You should probably install the event filter not on the TableWidget itself, but on ui->TableWidget->viewPort()

M_31

After changing into viewport()...
like
@
#include <QMouseEvent>
#include <QKeyEvent>
#include <QEvent>
CTestDlg::CTestDlg()
{
ui->setupUi(this);
ui->TableWidget->setSelectionMode( QAbstractItemView::ExtendedSelection );
ui->TableWidget->setMouseTracking( true );
ui->TableWidget->viewport()->installEventFilter( this );
}

bool CTestDlg::eventFilter(QObject *object, QEvent *event)
{

if (event->type() == QEvent::MouseButtonPress )
{
qDebug()<<"MOUSE BUTTON PRESSED @";
if ( object == ui->TableWidget )
{
QTableWidgetItem *item = ui->TableWidget->currentItem();
qDebug()<<item->row()<<":"<<item->column();
}
return QObject::eventFilter(object, event);
}
else if (event->type() == QEvent::MouseButtonRelease )
{
qDebug()<<"MOUSE BUTTON RELEASED @";
if ( object == ui->TableWidget )
{
QTableWidgetItem *item = ui->TableWidget->currentItem();
qDebug()<<item->row()<<":"<<item->column();
}
return QObject::eventFilter(object, event);
}
return QObject::eventFilter(object, event);

}
@

Now i am getting only the "MOUSE BUTTON PRESSED @" & "MOUSE BUTTON RELEASED @"

but not the item row or column value..!!!

giesbert

object is not the tableview, it's the view port!

@
bool CTestDlg::eventFilter(QObject *object, QEvent *event)
{
if (event->type() == QEvent::MouseButtonPress )
{
qDebug()<<"MOUSE BUTTON PRESSED @";
if ( object == ui->TableWidget->viewport() ) // changed here
{
QTableWidgetItem *item = ui->TableWidget->currentItem();
qDebug()<<item->row()<<":"<<item->column();
}
return QObject::eventFilter(object, event);
}
else if (event->type() == QEvent::MouseButtonRelease )
{
qDebug()<<"MOUSE BUTTON RELEASED @";
if ( object == ui->TableWidget->viewport() ) // changed here
{
QTableWidgetItem *item = ui->TableWidget->currentItem();
qDebug()<<item->row()<<":"<<item->column();
}
return QObject::eventFilter(object, event);
}
return QObject::eventFilter(object, event);
}
@

andre

Note that lines 11 and 21 do nothing in the example above. At least, nothing that line 23 would not do just as well... ;-)

Edit:
comment is obviously pointed at M_31, not at Gerolf :-)

giesbert

I only fixed the compare statement, not optimized the whole code ;-)

luca72

There is a way to know if is the right or left button thet he press?

Luca

giesbert

Cast the event to a QMouseEvent and use the members

M_31

Now i am able to get the co-ordinates from mouse press & release event

@
if( object == ui->TableWidget->viewport() )
{
QMouseEvent mouseEvent = static_cast <QMouseEvent>( event );
qDebug()<<"MouseButtonPress event!@"<<mouseEvent->x()<<":"<<mouseEvent->y();

        QTableWidgetItem *item =  ui->TableWidget->currentItem();
       // qDebug()<<"ITEMS !@"<<item->row()<<":"<<item->column();

//This line is not working ..my app is getting crashing ..saying that ..No value found in "item"

@

Is there any other to get the QTableWidget row & column value using mouse event other than X & Y
co-ordinates....

giesbert

[quote author="M_31" date="1316014954"]Now i am able to get the co-ordinates from mouse press & release event

@
if( object == ui->TableWidget->viewport() )
{
QMouseEvent mouseEvent = static_cast <QMouseEvent>( event );
qDebug()<<"MouseButtonPress event!@"<<mouseEvent->x()<<":"<<mouseEvent->y();

        QTableWidgetItem *item =  ui->TableWidget->currentItem();
       // qDebug()<<"ITEMS !@"<<item->row()<<":"<<item->column();

//This line is not working ..my app is getting crashing ..saying that ..No value found in "item"

@

Is there any other to get the QTableWidget row & column value using mouse event other than X & Y
co-ordinates....[/quote]

No, it is not.

The only way is to use "indexAt":http://doc.qt.nokia.com/latest/qabstractitemview.html#indexAt

luca72

Hello i have one question :

@bool Widget::eventFilter(QObject *object, QEvent *event){
if (object == ui->tableWidget->viewport()){
QMouseEvent mouseEvent = static_cast<QMouseEvent>(event);
if (mouseEvent->button()==2){
messaggio = new QMessageBox;
messaggio->information(this,tr("Packing"),tr("Tasto destro schiacciato"),messaggio->Ok);
}
}
}@

Why the message is open two time when i click the right button?

Thanks

Luca

giesbert

it is called for mousepress and mouserelease... :-)
and you even do not check, which one is called...

@
bool Widget::eventFilter(QObject *object, QEvent *event)
{
if (object == ui->tableWidget->viewport())
{
QMouseEvent mouseEvent = static_cast<QMouseEvent>(event);
if ((QEvent::MouseButtonPress == event->type()) && (mouseEvent->button()==Qt::RightButton))
{
messaggio = new QMessageBox;
messaggio->information(this,tr("Packing"),tr("Tasto destro schiacciato"),messaggio->Ok);
}
}
}
@

Additionally, I suggest not to use magic numbers, if there are enums that can be used...

M_31

Thanks Gerolf...for your valuable inputs..
Its working fine with viewport and i achived my task...

timswoosh

Hi, everyone!

I had a similar problem and used a similiar approach to it, but I faced an obstacle when used method QTableWidget::itemAt: it uses coordinates relative to the left upper corner of data cells and doesn't take to account header cells!
So, when I transformed global coordiantes to the widget's ones via QWidget::mapFromGlobal I obtained not what I needed at all!
It gave me coordinates relative to the left upper corner of the widget itself, not the data cells.
How can I obtain the proper coordinates?

I wanted to try methods QTableView::horizontalOffset() and QTableView::verticalOffset(), but they are protected :(
(Sorry for my English, it's not my native language)

[quote author="Gerolf" date="1316016131"]
No, it is not.

The only way is to use "indexAt":http://doc.qt.nokia.com/latest/qabstractitemview.html#indexAt[/quote]

timswoosh

Hi, everyone!

I had a similar problem and used a similiar approach to it, but I faced an obstacle when used method QTableWidget::itemAt: it uses coordinates relative to the left upper corner of data cells and doesn't take to account header cells!
So, when I transformed global coordiantes to the widget's ones via QWidget::mapFromGlobal I obtained not what I needed at all!
It gave me coordinates relative to the left upper corner of the widget itself, not the data cells.
How can I obtain the proper coordinates?

I wanted to try methods QTableView::horizontalOffset() and QTableView::verticalOffset(), but they are protected :(
(Sorry for my English, it's not my native language)

[quote author="Gerolf" date="1316016131"]
No, it is not.

The only way is to use "indexAt":http://doc.qt.nokia.com/latest/qabstractitemview.html#indexAt[/quote]

andre

Well, as you can see from the QAbstractScrollArea documentation, of which QTableWidget is derived, the actual scrolling area is provided by a widget called viewport. That widget can be also be used for your coordinate transformations.

andre

Well, as you can see from the QAbstractScrollArea documentation, of which QTableWidget is derived, the actual scrolling area is provided by a widget called viewport. That widget can be also be used for your coordinate transformations.

timswoosh

Thank you, that's what I need!
Sorry I failed to find it myself...

I guess it would be advisable to add a link to viewport() member into QTableWidgetItem::itemAt() documentation.

[quote author="Andre" date="1421132571"]Well, as you can see from the QAbstractScrollArea documentation, of which QTableWidget is derived, the actual scrolling area is provided by a widget called viewport. That widget can be also be used for your coordinate transformations.[/quote]

timswoosh

Thank you, that's what I need!
Sorry I failed to find it myself...

I guess it would be advisable to add a link to viewport() member into QTableWidgetItem::itemAt() documentation.

[quote author="Andre" date="1421132571"]Well, as you can see from the QAbstractScrollArea documentation, of which QTableWidget is derived, the actual scrolling area is provided by a widget called viewport. That widget can be also be used for your coordinate transformations.[/quote]

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[ SOLVED ]Problem in getting mouseEvent on QTableWidget