ionic2(angular2) Cannot read property 'toUrlPath' of null

I have the following code:

  <a href="#index_a">Go</a>
  <h3 id="index_1">A</h3>

When i click on <a> tag, angular2 throw this exception: EXCEPTION: TypeError: Cannot read property ‘toUrlPath’ of null

What is that error?
Please help me fix that error!

Thanks in advance~

are you using the Ionic nav component? Ionic 2 uses ‘LIFO’ stack as navigation, because of that url navigation doesn’t make sense, there’s some issues and forum posts about adding support for url navigations but idk if it’s added jet or if it will be.