i'm trying to select my combobox items with only one click, but, when clicked once, this doesn't works, just when i click two times this has been selected, but i don't need that. But, here's an interesting (weird) thing, sometimes works with one click and other times with the double click.

here's my code:

Code:
items: [{
    xtype: 'combo',
    anchor: '100%',
    padding: 10,
    fieldLabel: 'Type',
...