Fix NPE if dismiss() is called before show()

[SUPERCILEX]

Upgrading to v2.2+ gives me this crash:

11-03 20:50:19.714 19598-19598/com.supercilex.robotscouter.debug E/UncaughtException: java.lang.NullPointerException: Attempt to invoke virtual method 'android.os.LocaleList android.text.TextPaint.getTextLocales()' on a null object reference
                                                                                          at android.text.StaticLayout.generate(StaticLayout.java:608)
                                                                                          at android.text.StaticLayout.<init>(StaticLayout.java:588)
                                                                                          at android.text.StaticLayout.<init>(Unknown Source:0)
                                                                                          at android.text.StaticLayout$Builder.build(StaticLayout.java:399)
                                                                                          at uk.co.samuelwall.materialtaptargetprompt.extras.PromptUtils.createStaticTextLayout(PromptUtils.java:240)
                                                                                          at uk.co.samuelwall.materialtaptargetprompt.extras.PromptText.createTextLayout(PromptText.java:237)
                                                                                          at uk.co.samuelwall.materialtaptargetprompt.extras.PromptText.update(PromptText.java:263)
                                                                                          at uk.co.samuelwall.materialtaptargetprompt.MaterialTapTargetPrompt.updateAnimation(MaterialTapTargetPrompt.java:473)
                                                                                          at uk.co.samuelwall.materialtaptargetprompt.MaterialTapTargetPrompt$5.onAnimationUpdate(MaterialTapTargetPrompt.java:311)
                                                                                          at android.animation.ValueAnimator.animateValue(ValueAnimator.java:1522)
                                                                                          at android.animation.ValueAnimator.setCurrentFraction(ValueAnimator.java:654)
                                                                                          at android.animation.ValueAnimator.setCurrentPlayTime(ValueAnimator.java:617)
                                                                                          at android.animation.ValueAnimator.start(ValueAnimator.java:1046)
                                                                                          at android.animation.ValueAnimator.start(ValueAnimator.java:1065)
                                                                                          at uk.co.samuelwall.materialtaptargetprompt.MaterialTapTargetPrompt.dismiss(MaterialTapTargetPrompt.java:328)
                                                                                          at com.supercilex.robotscouter.util.ui.TutorialUtilsKt$showAddTeamTutorial$1.onChanged(TutorialUtils.kt:42)
                                                                                          at com.supercilex.robotscouter.util.ui.TutorialUtilsKt$showAddTeamTutorial$1.onChanged(TutorialUtils.kt:21)
                                                                                          at android.arch.lifecycle.LiveData.considerNotify(LiveData.java:131)
                                                                                          at android.arch.lifecycle.LiveData.dispatchingValue(LiveData.java:148)
                                                                                          at android.arch.lifecycle.LiveData.setValue(LiveData.java:294)
                                                                                          at android.arch.lifecycle.MutableLiveData.setValue(MutableLiveData.java:33)
                                                                                          at com.supercilex.robotscouter.util.data.UniqueMutableLiveData.setValue(DatabaseUtils.kt:167)
                                                                                          at com.supercilex.robotscouter.ui.teamlist.TutorialHelper.onDataChanged(TutorialHelper.kt:45)
                                                                                          at com.firebase.ui.common.BaseObservableSnapshotArray.notifyOnDataChanged(BaseObservableSnapshotArray.java:163)
                                                                                          at com.firebase.ui.firestore.FirestoreArray.onEvent(FirestoreArray.java:92)
                                                                                          at com.firebase.ui.firestore.FirestoreArray.onEvent(FirestoreArray.java:21)
                                                                                          at com.google.firebase.firestore.zzi.onEvent(Unknown Source:16)
                                                                                          at com.google.android.gms.internal.zzejz.zza(Unknown Source:6)
                                                                                          at com.google.android.gms.internal.zzeka.run(Unknown Source:6)
                                                                                          at android.os.Handler.handleCallback(Handler.java:790)
                                                                                          at android.os.Handler.dispatchMessage(Handler.java:99)
                                                                                          at android.os.Looper.loop(Looper.java:164)
                                                                                          at android.app.ActivityThread.main(ActivityThread.java:6494)
                                                                                          at java.lang.reflect.Method.invoke(Native Method)
                                                                                          at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
                                                                                          at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)

I have a database listener which only knows if a user has tapped a prompt or not. I use an observable model that shows or dismisses the prompt based on that boolean flag. Thus, I have no knowledge of the current state of the prompt, just the state it should be in. This means I'll be possibly calling dismiss() before show() which causes the above NPE.

To fix this problem, we now save our current state instead of the limited mDismissing field. In addition, I've added a getState() method though that isn't necessary to fix the bug.

[codecov-io]

Codecov Report

Merging #87 into master will decrease coverage by 0.36%.
The diff coverage is 23.07%.

@@             Coverage Diff              @@
##             master      #87      +/-   ##
============================================
- Coverage     93.82%   93.46%   -0.37%     
- Complexity      300      308       +8     
============================================
  Files            14       14              
  Lines          1020     1025       +5     
  Branches        117      117              
============================================
+ Hits            957      958       +1     
- Misses           39       40       +1     
- Partials         24       27       +3

Impacted Files	Coverage Δ	Complexity Δ
...terialtaptargetprompt/MaterialTapTargetPrompt.java	83.83% <23.07%> (-1.1%)	29 <12> (+8)

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[sjwall]

Thanks for your pull request the changes have been released in v2.4.0

[SUPERCILEX]

Awesome!