Tab content gets removed

Hey Ninjas, anyone can help me
I have an app which has side menu navigation.
Now in one view which shows entry details I have two tabs.
My problem is that as soon as I change tab the content of the other tab is gone.
My view code is like this:

<ion-view view-title="main view title">

<ion-tabs tabs-type="tabs-icon-top" class="tabs-striped tabs-color-active-positive">

   <ion-tab  title="General">

<ion-content class="has-subheader padding text-center">

   Test general
  
</ion-content>
   </ion-tab>

   <ion-tab title="Documents">

<ion-content class="has-subheader padding">

test document

   </ion-content>

   </ion-tab>

</ion-tabs>

</ion-view>