Hi,all
​   Now I have two naviframe item –view1,view2, view1 navigated to view2,  currently view2 is the top item of the naviframe, I have a such function:

1.when user press hardware back button only one time, the naviframe don’t pop item, and

2. if press hardware back button twice time quickly,naviframe pop view2 and navigated to view1.

How can I do that ,thanks.