android ActivityOptions.isReturning() NullPointerException

Question

In which case I have

java.lang.NullPointerException: Attempt to invoke virtual method 'boolean android.app.ActivityOptions.isReturning()' on a null object reference

I cannot understand why EnterActivityOptions.isReturning() in ActivityTransitionState give me null?

Please have a look through this : [How do I ask a good question?](http://stackoverflow.com/help/how-to-ask) — Apurva, Apr 14 '16 at 08:44
https://android.googlesource.com/platform/frameworks/base/+/777f5b2/core/java/android/app/ActivityTransitionState.java#196 — Rayna Ivanova, Apr 14 '16 at 09:25
You need to add more context to your question. The `ActivityOptions.isReturning` method is not part of the public API neither is the `ActivityTransitionState` you referenced. — Kingsley Adio, Jul 19 '16 at 01:27
please improve this question, its really hard to understand how you are even using a hidden api. — petey, Jul 19 '16 at 17:02
http://stackoverflow.com/questions/17035271/what-does-hide-mean-in-the-android-source-code — Rohit Arya, Jul 24 '16 at 04:36

score 4 · Answer 1 · answered Jul 18 '16 at 23:37

4

Try with support library 24.1.0 (released today, but not sure if this fix your problem)

answered Jul 18 '16 at 23:37

Daniel Gomez Rico

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I just tried using 24.1.0 but maybe its not live yet. Because it couldn't find the design library. – Etienne Lawlor Jul 19 '16 at 00:03
weird since the changelog is already there https://developer.android.com/topic/libraries/support-library/revisions.html – Daniel Gomez Rico Jul 19 '16 at 11:36
Now its live. But that doesn't fix this issue. – Etienne Lawlor Jul 19 '16 at 19:48
It crashes with this statement `getActivity().supportStartPostponedEnterTransition();` – Etienne Lawlor Jul 19 '16 at 20:20
1

Looks like `getActivity()` is returning null, where are you calling that? are you using fragments right? – Daniel Gomez Rico Jul 19 '16 at 20:39
I am using fragments. getActivity() is not returning null. For some reason the activityoptions are null but i explicitly set them when starting a new activity. – Etienne Lawlor Jul 19 '16 at 21:42
1

I added a try {} catch(NullPointerException e){} to catch this exception and then it proceeds as usual without an issue. still not sure why its throwing this exception. In my case it will get thrown on a Samsung S5 and not a Nexus 5X. – Etienne Lawlor Oct 10 '16 at 22:38

Bethan · Answer 2 · 2016-10-12T06:56:43.417

I believe the problem is with the variable EnterActivityOptions When I look into your code sample it's look like you assigned some value to EnterActivityOptions in the method of setEnterActivityOptions

But I am not sure that this method is calling when you invoke the activity.

if it's not calling the method then obviously it will not be initialized and the variable value will be null this results NullPointerException.

So, to resolve this issue please try to check the case whether EnterActivityOptions is null or not and then use the condition

if (mEnterActivityOptions.isReturning()) {
    Your code will place here
}

score -2 · Answer 3 · edited Dec 13 '17 at 00:16

-2

On API 21, only one call to startPostponedEnterTransition is allowed

edited Dec 13 '17 at 00:16

Jon

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answered Dec 12 '17 at 20:04

Dmitry DG-SC

1

android ActivityOptions.isReturning() NullPointerException

3 Answers3