QLineEdit focus problem

[matteo.cozzaglio]

Hi all,
I have a problem with the focus for the widget QLineEdit.
This is what append:
I have a QMainWindow that show a QDialog that contains the QLineEdit widget.
If I try to insert text i can not see any change on it, only when I pass the focus to an other control I can see what I have entered in the QLineEdit.
I think that is a problem on the focus. I have tried to change the focus policy of the QLineEdit but the result is the same.

This is the code that I use for show the QDialog

void show_ControlPanel()
{
   frm_ControlPanel *ControlPanel;
    ControlPanel = new frm_ControlPanel();
    ControlPanel->setModal(true);
    ControlPanel->show();
}

void show_ControlPanel()
{
   frm_ControlPanel *ControlPanel;
    ControlPanel = new frm_ControlPanel();
    ControlPanel->setModal(true);
    ControlPanel->show();
}

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How can I do for solve this problem?
I use Qt Creator 1.2.0 on OSX

Thanks in advance