Ionic2 app break in first time run but work perfectly in subsequent times

Hi every one,
I have created a custom tab in ionic 2. You can see my work in git repository GitHub - duannx/ionic2-custom-tab: A custom tab for ionic 2. My problem is my app run terribly in first time (both in browser and device). But when i refresh browser or re-launch my app, it work perfectly and all bug disappear forever. I have no idea why. Could someone take a look and give me some advices please.
Many thanks.
Here is system info:

Cordova CLI: 6.4.0
Ionic Framework Version: 2.0.0-rc.5
Ionic CLI Version: 2.2.1
Ionic App Lib Version: 2.2.0
Ionic App Scripts Version: 1.0.0
ios-deploy version: Not installed
ios-sim version: Not installed
OS: Windows 7
Node Version: v6.9.1
Xcode version: Not installed

P/S: Sorry for my bad english.