manipulating qmainwindow widget through qdialog

hi, i have a qtablewidget in my mainwindow and when a dialog opens, there is a bunch of qlinedit and when i click the button add in the qdialog, the data in the qlinedits must be inserted in the qtablewidget in the mainwindow without closing the qdialog coz i have to insert another data in the qtablewidget but the problem is that the data is not reflected in the qtablewidget.

mainwindow has a public slot for the qdialog to call. it run bcoz i tried to put a qmessagebox in each line but the qtablewidget setItem is not working.

help what is wrong with it?

solution : http://developer.qt.nokia.com/forums/viewthread/2446/