add button to MainPlayer to go to Detail view

[csicar]

• I carefully read the contribution guidelines and agree to them.

Changes

• Added a <- button to the top of the MainVideoPlayer

Reason

The reason this button is useful is, that when opening videos via a link (and having selected "Open Video directly"), you can see the comments and related videos.

Example

[Stypox]

I think the code is good, since it has the same structure as the code around it. The style inconsistencies I pointed out are nothing important :-)
Thank you for this feature! 😄

[csicar]

Requested changes have been implemented. Is there something else missing?

[Stypox]

Please wait for a maintainer to review your changes. This could take a while since they are often busy in real life and there are more important and complex PRs on the way to be merged.

[AdKiller]

Always wanted this feature. thank you very much for implementing it!

[TobiGr]

Code looks good 👍 Will test it later.

[Phoenix616]

I feel like making the button look like a back button kinda breaks expectations: Back implies that you actually go back to the previous screen (like with the device back button), not that you always go to the info page.

I feel like a design that clearly shows the info page (e.g. an i in a circle) and a different placement would solve that.

[Stypox]

@Phoenix616 you are right, an info button would be better. This expectation-breaking already exists with other back button: #2358. The proposed fix is basically the same as yours: #2358 (comment).
@csicar would you mind changing the back button to some type of info button?

[csicar]

The bahaviour oft the back butto is how Android UIs are intended to behave (as intended by the ui guidelines):

• the Back Button in the toolbar of an app should navigate hierachically upwards
• the android's system back button navigates chronologically backwards.

Reference: https://material.io/design/navigation/understanding-navigation.html#reverse-navigation

I personally perfer to think of the Button as navigating upwards, but I can understand the Argument. Maybe the down arrow from YouTube's app could be a compromise?

If not, i'll be happy to implement to info button.

[Stypox]

For me the back button is ok, then 😉

[Phoenix616]

Interesting that they would suggest such a confusing way of handling things. (Duplicate back buttons with different functionality) I feel like the down arrow would be a lot better and more intuitive. (Especially for people coming from the original app ;))

[csicar]

Example of how it looks with the "expand" button:

patch.txt

[csicar]

@Phoenix616 I guess having very similar symbols for the different actions doesn't help :)

[TobiGr]

I am completely fine with the behaviour and icons you used in the example video 👍

[Phoenix616]

I realise that the downwards arrow causes another usability problem: The arrow at the right side looks the same but it is used to expand the view of available video options instead.

So a backwards arrow like the Android docs suggest might actually be the better option here :S (unless a different icon can be found for either going to the info view or expanding the option view I guess)

[TobiGr]

@Stypox is there anything which prevents this PR from being merged?

[Stypox]

@TobiGr no, this is ready, I forgot to approve changes at last ;-)

[TobiGr]

I got the following exception with autoplay enabled and watching three videos (so the initial video was not opened, but another one).

Exception

• User Action: ui error
• Request: App crash, UI failure
• Content Language: GB
• Service: none
• Version: 0.17.3
• OS: Linux ,release-keys 6.0 - 23

Crash log

java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.res.Resources android.view.View.getResources()' on a null object reference
	at org.schabi.newpipe.util.AnimationUtils.slideUp(AnimationUtils.java:372)
	at org.schabi.newpipe.fragments.list.comments.CommentsFragment.handleResult(CommentsFragment.java:96)
	at org.schabi.newpipe.fragments.list.comments.CommentsFragment.handleResult(CommentsFragment.java:25)
	at org.schabi.newpipe.fragments.list.BaseListInfoFragment.lambda$startLoading$0(BaseListInfoFragment.java:120)
	at org.schabi.newpipe.fragments.list.-$$Lambda$BaseListInfoFragment$prYfqK19mXhZc0JDsOoy9kGzYpE.accept(lambda)
	at io.reactivex.internal.observers.ConsumerSingleObserver.onSuccess(ConsumerSingleObserver.java:62)
	at io.reactivex.internal.operators.single.SingleObserveOn$ObserveOnSingleObserver.run(SingleObserveOn.java:81)
	at io.reactivex.android.schedulers.HandlerScheduler$ScheduledRunnable.run(HandlerScheduler.java:119)
	at android.os.Handler.handleCallback(Handler.java:746)
	at android.os.Handler.dispatchMessage(Handler.java:95)
	at android.os.Looper.loop(Looper.java:148)
	at android.app.ActivityThread.main(ActivityThread.java:5443)
	at java.lang.reflect.Method.invoke(Native Method)
	at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728)
	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)

---

[Stypox]

@csicar could you check the bug report from TobiGr?

[Stypox]

Closing as this isn't needed anymore after #2907