ComboBox selection behavior is eratic

QComboBox is behaving strange when used together with a model.

Please build and run the attached demo.

You will see a combobox with a QStandardItemModel containing four text items.

Then you got a button, clicking that will print the data found in comboBox->view()->currentIndex()

Finally there is a label to print the data into.

How to reproduce:

1) Start the application.

2) click on button

Expected result:
"Item 1" is printed.

Actual result:
"<NOTHING>" is printed: There is currently no current item!

3) Open the combobox and click on "Item 1"

4) Click the button

Expected result:
"Item 1" is printed

Actual result:
"Item 1" is printed. Nice

5) Open the combobox again, hover (do not click) "Item 3" and then close the combobox again by clicking outside of the popup area.

6) Click the button

Expected result:
"Item 1" is printed

Actual result:
"Item 3" is printed