Tweaks values not loading until an activity is stopped and resumed

[AamirAbro]

We have a teak defined in app and on mixpanel and the experiment is joined and mixpanel lib continue to return the default value until we move app to background or open some other activity and com back to the previous activity.
ie: until pause/stop or start/resume lifecycle events on the main activity the uses that tweak are called.

Mixpanel lib version 4.9.3.

Let me know if you need more info.

[AamirAbro]

any update guys! let me know how can help or if you need more info/context.

[cassiegamm]

Hi @AamirAbro,

By default, applications will only attempt to join available experiments any time an activity is resumed, but you can disable this automatic behavior by adding the following tag to the in your AndroidManifest.xml

<meta-data android:name="com.mixpanel.android.MPConfig.AutoShowMixpanelUpdates" android:value="false" />

If this tag is already set to false: is your app utilizing joinExperimentIfAvailable and OnMixpanelUpdatesReceivedListener to join (or clear) existing experiments?

If it helps, there's a bit more detail here:

mixpanel-android/src/main/java/com/mixpanel/android/mpmetrics/MixpanelAPI.java

Lines 1139 to 1154 in 337958c

	/**
	* Applies A/B test changes, if they are present. By default, your application will attempt
	* to join available experiments any time an activity is resumed, but you can disable this
	* automatic behavior by adding the following tag to the <application> tag in your AndroidManifest.xml
	* {@code
	* <meta-data android:name="com.mixpanel.android.MPConfig.AutoShowMixpanelUpdates"
	* android:value="false" />
	* }
	*
	* If you disable AutoShowMixpanelUpdates, you'll need to call joinExperimentIfAvailable to
	* join or clear existing experiments. If you want to display a loading screen or otherwise
	* wait for experiments to load from the server before you apply them, you can use
	* {@link #addOnMixpanelUpdatesReceivedListener(OnMixpanelUpdatesReceivedListener)} to
	* be informed that new experiments are ready.
	*/
	public void joinExperimentIfAvailable();

[xX7]

We are experiencing the same issue like @AamirAbro, @cassiegamm.

Pseudo - Code:

public class MainActivity{

public static Tweak<Boolean> mABShow = MixpanelAPI.booleanTweak("Test Var 1", true);

    @Override
    protected void onCreate(Bundle savedInstanceState) {
          mixpanelAPI = MixpanelAPI.getInstance(this, "XXXX");
     }

    @OnClick
    public void pseudoButtonClick(){
	startActivity(SecondActivity.class);
    }

    @Override
    protected void onDestroy() {
        if(mixpanelAPI != null){
            mixpanelAPI.flush();
        }
        super.onDestroy();
    }

}




public class SecondActivity{

    @Override
    protected void onCreate(Bundle savedInstanceState) {
          Log.e("test", MainActivity.mABShow.get()); <- Default Value
     }

}

Now If you start a Activity, directly from the MainActivity and check the value of mABShow, it will return the default value. You have to "restart" the Activity first in order to get the right value.

[rosconabn]

If you use the keys into another class, make them initialized from the App first

• in the class add
  public static Tweak userAB; // So it is null

• init in this class with some method
  userAB = MixpanelAPI.booleanTweak("userAB", false);

• call it from the YOURAPP or MAINACTIVITY
  Then set your identity and joinforexperiments ,

• make sure to check the tweak listener and you should be done.

in case someone needs to get the stuff done on time.. then call mixpanel.flush()!!!!

[xX7]

The Solution from @cassiegamm worked perfectly! Just in case someone reads this and has the same issue!

[AamirAbro]

But the experiment is already joined I can see that in the logs but first time it always gives the default value of tweak and the the tweak value is not retained across app restarts, as far as I know only andorid SDK has these issues I talked to iOS developer he said they don't​ face these issues. I would suggest to keep this thread open and try to have some good default implementation.

[rosconabn]

@AamirAbro try as I did, I use both android and ios and now all works fine.
I also had timing issues between screens and this really fix the problem.
Also for android when you get the value try to broadcast the value.
but mostly use the flush! I think is the key of your issues.

[rosconabn]

@xX7 doesn't mean it works for you it works for everybody. Don't assume anything, find the solution not the party dancing.

[dinhthaidaica]

@rosconabn @xX7 could you please provide your sample? I have the same issue with @AamirAbro and still can not fix it

[Tsepaka]

I can confirm, that I have the same issue as @AamirAbro. Tweak values are not retained across app launches, and tweak.get() return the default value until activity is re-launched. However, in logs, I can see, that correct value for the experiment is retrieved from server.

[patedit]

Starting on version 5.2.0, we now persist tweak across app sessions.
@Tsepaka the logs that you see is what the server sends back, but it does not mean it's automatically applied. You'd need to go into a new activity to apply the tweaks automatically or by calling mMixpanel.getPeople().joinExperimentsIfAvailable().