Performance issue for ion-tabs

I have created a ionic tabs project using ion-tabs component. But the issue is when user clicks on tab icon, tab is not changed immediately. It takes 1-2 seconds to switch the tabs.

HTML Code:

<ion-tabs  class="footer-tabs" selectedIndex="selectedTabIndex"#footerTabs>
  <ion-tab tabIcon="list" tabTitle="'Notice'" [root]="noticepage"></ion-tab>
  <ion-tab tabIcon="book1" tabTitle="'Homework'" [root]="homeworkpage"></ion-tab>
  <ion-tab tabIcon="calendar1" tabTitle="'Event'" [root]="eventpage"></ion-tab>
  <ion-tab tabIcon="list-box1" tabTitle="'Attendance'" [root]="attendancepage"></ion-tab>

If I create new tabs project, then the component is working fine. But its giving issues in my project. I also tried by removing methods called on the ionPageDidEnter() for all the pages.

Does anyone know what could be the possible issue ?