iOS navigation bug

[NickIliev]

From @denkomanceski on May 24, 2016 21:7

There are two bugs involved here.

The first one is when I start navigating back on iOS (slowly sliding left to right) the action bar is losing the styling (its going white with blue letters) and the components on the page are disappearing.

The second one which is worse is if you dont navigate back but stay on the page after you trigger the navigation transition (slide back to the same view instead of navigating back) the app crashes (before it crashes bug no.1 comes and the page is blank).

Here is a video: https://www.dropbox.com/s/tfz18kuhyottcuc/IMG_2936.MOV?dl=0
(First I show the first bug, than both together)

Is there any workaround that could help?

Edit: I tried with the ng-sample app (the NavigationTest, the one that is using page router and normal router) and the excatly same error happens. Here is the error also:

file:///app/tns_modules/rxjs/Subscriber.js:229:22: JS ERROR TypeError: undefined is not an object (evaluating 'state.isPageNavigation')
May 24 23:30:13 DenkoMBP com.apple.CoreSimulator.SimDevice.B0C93223-F914-47B3-97F0-E6B1D8739AE5.launchd_sim[11323] (UIKitApplication:org.nativescript.ngsample[0xfa7][11393]): Service exited due to signal: Segmentation fault: 11

Thanks

Copied from original issue: NativeScript/NativeScript#2168

[NickIliev]

Hello @denkomanceski

I can confirm that indeed in nativescript-angular project the navigation is throwing error when you initiate swipe-back but still stay on the same page.

I have moved your issue to the nativescript-angular repository to log this bug and i will create another issue for the first problem with the styling of transitioned action bar.

[denkomanceski]

@vakrilov does this also fixes the part "the action bar is losing the styling (its going white with blue letters) and the components on the page are disappearing." ? If it is how can we start using this version since the app is currently unusable?

Thanks

[vakrilov]

@denkomanceski Not sure about the styling. The components on the page that you are navigating back from should remain there until the navigation is completed. If you cancel it - they will be still alive.

[denkomanceski]

I tried it, it works and doesnt throw errors but the action bar color is still changing to default just to let you know

Edit: Actually I think when you start navigating back, the action bar gets the color from the previous page (since the action bar on the previous page is hidden it uses the default white and blue color). If I go one page deeper and navigate back and go back its fine because they have the same color. Maybe this is iOS behaviour or just like this fix it needs to change the color on navigation finished or something
Edit2: I tried setting the color to the previous page and it works now, which means when I start transitioning back it is getting the color from the previous page right away instead of when the transition is finished (again, maybe that is the iOS behavior but not sure)

[vakrilov]

Thanks for the updates.
I'm not sure about if this is default IOS behavior. However, this particular behavior is not specific for the angular-nativescript so the NativeScript repo will be the right place to continue the discussion if needed.