SEnding data between forms

[core_st]

I have MainWIndow. From that window i create dialog Window with table.

WideSearch* wWideSearch=new WideSearch;
 wWideSearch->setSourceModel (createRecordModel(wWideSearch));
wWideSearch->show();
wWideSearch->raise();
wWideSearch->activateWindow()

WideSearch* wWideSearch=new WideSearch;
 wWideSearch->setSourceModel (createRecordModel(wWideSearch));
wWideSearch->show();
wWideSearch->raise();
wWideSearch->activateWindow()

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On double click on table i need close dialog Window and send data from QModelIndex to mainWindow. With closing second form there is no problem,but i don't know how send data back to mainWindow?