Add initial index in TabPage widget

[Nic-DB]

Added the possibility to choose the initial tab selected in the TabPage widget

[tomgilder]

Hello, thanks for the submission, but why do you need this functionality?

The idea of Routemaster is that the active tab is driven by the current path.

[Nic-DB]

In my case the tab page is my home and I wanted to land in the second tab, I was able to do it with a workaround but in the end i found this solution cleaner. Maybe there is another way that I couldn't see, if you can help me out it would be perfect!

[anthonysette]

Hi there, I also was looking for a solution to this in the past. In my situation, it was a tab view for login and register. Our designs indicated that Register should be the left tab, and Login should be the right tab. However, in most situations, we would want to show the login tab first. So an initial index would have been helpful, what we did instead changed the paths of those tabs from "/" to "/auth/", and use the unknown route handler to direct the user to the second tab by default.

It would have been cleaner for us as well to use an initial index, or if we could have specified a default path.

I see the benefit of this PR @tomgilder, let me know if there is another way to handle something like this.

[Nic-DB]

Hi sorry to bother you again do you have any news about this pr? Thank you in advance for your time