Ion-tabs and ion-nab-view navigation history not working

i m using ion-tabs and ion-nav-view to create a UI similar as that of whatsapp.
in which there are tabViews and when a user selects a contact, a chat window should open without tabs at bottom and a navigation back button to go back.

however i have used

<ion-view> <ion-tabs ......

for tabs and chat view

<ion-view view-title="{{chatId}}">
    <ion-content

the problem is that the back button is not displayed automatically. but when in browser i manually do a back, then the navigation’s back button is displayed but that to alternatively. i.e. it is not displayed for the first time, then on doing a manual back and again selecting the same contact the chat View is displayed with a back button. the back button is displayed exactly alternatively each time.