Accordion activeIndex doesn't work initially

[DanielChicot]

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Plunkr Case (Bug Reports)

https://plnkr.co/edit/9evYJTUINseQ3syIlNQY

Current behavior
After upgrading to primeng 5 using an array of integers for activeIndex couple d with multiple = true doesn't seem to work. No tabs are open.

Expected behavior
The tabs specified in the activeIndex property should be open

Minimal reproduction of the problem with instructions

Please see example at:
https://plnkr.co/edit/9evYJTUINseQ3syIlNQY

What is the motivation / use case for changing the behavior?

So that is works as described in the documentation.

Please tell us about your environment:

Linux, emacs, yarn, node.

• Angular version: 2.0.X
  5.0.0

• PrimeNG version: 2.0.X
  5.0.1

• Browser: [all | Chrome XX | Firefox XX | IE XX | Safari XX | Mobile Chrome XX | Android X.X Web Browser | iOS XX Safari | iOS XX UIWebView | iOS XX WKWebView ]

Chrome. Firefox

• Language: [all | TypeScript X.X | ES6/7 | ES5]
  Typescript 2.4.2

• Node (for AoT issues): node --version =
  9.2.0

[nartc]

For some reason, openTabs(): number[] { return this._openTabs.map(tab => tab); } works. It might actually require you to make change to the activeIndex array to trigger the tabs.

[DanielChicot]

Great, so it does, thanks so much,