Fix nav_bar_button class method

[jeffcarbs]

Fixes #666

Previously nav_bar_button would set an instance variable with the arguments for the last button added. This updates the nav_bar_button method to use an array to store the arguments so you can add multiple.

[jamonholmgren]

If you accidentally do left and then left again, will it record two entries in the array?

[jeffcarbs]

It would put two entries into the array. When the screen is initialized it would call set_nav_bar_button which would initialize a new button for each set of arguments and set leftBarButtonItem each time. So the last one for each side would win.

How do you think this should be handled?

• I see there's a set_nav_bar_buttons so we could theoretically use that somehow to allow someone to use multiple buttons per side.
• We could just store these as a hash with :left, :right, :back keys instead of an array so setting multiple times still means the last one wins but we wouldn't be initializing an extra button.

I kinda think the second one makes more sense since it's probably the more common use-case, but defer to you guys. I can fix up the PR either way.

[markrickert]

ping @jamonholmgren

[jamonholmgren]

Oh, sorry about this @jcarbo . lgtm!

[jamonholmgren]

I'll release a new version of ProMotion within a week.

[markrickert]

/slackbot remind me to release a new version of ProMotion in a week

😄

[jamonholmgren]

[jamonholmgren]

Released in 2.6.0: https://github.com/infinitered/ProMotion/releases/tag/v2.6.0