Error Inflating CountryCodePicker in new version 2.3.1

I use android X in my app. So i take the latest version of CountryCodePicker to use.
When i launch the fragment where is the widget, my app crash with this error : android.view.InflateException: Binary XML file line #44: Binary XML file line #44: Error inflating class com.hbb20.CountryCodePicker

Here is the stack

```
W/System.err: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ImageView.setVisibility(int)' on a null object reference
W/System.err: at com.hbb20.CountryCodePicker.refreshArrowViewVisibility(CountryCodePicker.java:478)
W/System.err: at com.hbb20.CountryCodePicker.applyCustomProperty(CountryCodePicker.java:309)
at com.hbb20.CountryCodePicker.init(CountryCodePicker.java:220)
at com.hbb20.CountryCodePicker.(CountryCodePicker.java:156)
at java.lang.reflect.Constructor.newInstance0(Native Method)
W/System.err: at java.lang.reflect.Constructor.newInstance(Constructor.java:334)
at android.view.LayoutInflater.createView(LayoutInflater.java:647)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:790)
W/System.err: at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:730)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:863)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)
W/System.err: at android.view.LayoutInflater.rInflate(LayoutInflater.java:866)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)
at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
W/System.err: at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
at io.kamix.kamix.ui.login.KamixLoginMobileFragment.onCreateView(KamixLoginMobileFragment.java:51)
at androidx.fragment.app.Fragment.performCreateView(Fragment.java:2439)
W/System.err: at androidx.fragment.app.FragmentManagerImpl.moveToState(FragmentManager.java:1460)
at androidx.fragment.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManager.java:1784)
at androidx.fragment.app.FragmentManagerImpl.moveToState(FragmentManager.java:1852)
W/System.err: at androidx.fragment.app.BackStackRecord.executeOps(BackStackRecord.java:802)
at androidx.fragment.app.FragmentManagerImpl.executeOps(FragmentManager.java:2625)
at androidx.fragment.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2411)
W/System.err: at androidx.fragment.app.FragmentManagerImpl.removeRedundantOperationsAndExecute(FragmentManager.java:2366)
at androidx.fragment.app.FragmentManagerImpl.execSingleAction(FragmentManager.java:2243)
W/System.err: at androidx.fragment.app.BackStackRecord.commitNowAllowingStateLoss(BackStackRecord.java:654)
at androidx.fragment.app.FragmentPagerAdapter.finishUpdate(FragmentPagerAdapter.java:146)
at androidx.viewpager.widget.ViewPager.populate(ViewPager.java:1244)
W/System.err: at androidx.viewpager.widget.ViewPager.populate(ViewPager.java:1092)
at androidx.viewpager.widget.ViewPager.onMeasure(ViewPager.java:1622)
at android.view.View.measure(View.java:22731)
W/System.err: at androidx.constraintlayout.widget.ConstraintLayout.internalMeasureChildren(ConstraintLayout.java:1227)
at androidx.constraintlayout.widget.ConstraintLayout.onMeasure(ConstraintLayout.java:1572)
at android.view.View.measure(View.java:22731)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6789)
W/System.err: at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at androidx.appcompat.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:143)
at android.view.View.measure(View.java:22731)
W/System.err: at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6789)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1514)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:806)
W/System.err: at android.widget.LinearLayout.onMeasure(LinearLayout.java:685)
at android.view.View.measure(View.java:22731)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6789)
W/System.err: at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at android.view.View.measure(View.java:22731)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6789)
W/System.err: at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1514)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:806)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:685)
at android.view.View.measure(View.java:22731)
W/System.err: at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6789)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at com.android.internal.policy.DecorView.onMeasure(DecorView.java:726)
W/System.err: at android.view.View.measure(View.java:22731)
at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2530)
at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1557)
W/System.err: at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1825)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1445)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:7013)
W/System.err: at android.view.Choreographer$CallbackRecord.run(Choreographer.java:921)
at android.view.Choreographer.doCallbacks(Choreographer.java:729)
at android.view.Choreographer.doFrame(Choreographer.java:664)
W/System.err: at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:907)
at android.os.Handler.handleCallback(Handler.java:790)
at android.os.Handler.dispatchMessage(Handler.java:99)
W/System.err: at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6524)
at java.lang.reflect.Method.invoke(Native Method)
W/System.err: at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:451)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:888)
D/AndroidRuntime: Shutting down VM
E/AndroidRuntime: FATAL EXCEPTION: main
Process: io.kamix.kamix, PID: 2863
android.view.InflateException: Binary XML file line #44: Binary XML file line #44: Error inflating class com.hbb20.CountryCodePicker
Caused by: android.view.InflateException: Binary XML file line #44: Error inflating class com.hbb20.CountryCodePicker
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Constructor.newInstance0(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:334)
at android.view.LayoutInflater.createView(LayoutInflater.java:647)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:790)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:730)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:863)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:866)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)
at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
at io.kamix.kamix.ui.login.KamixLoginMobileFragment.onCreateView(KamixLoginMobileFragment.java:51)
at androidx.fragment.app.Fragment.performCreateView(Fragment.java:2439)
at androidx.fragment.app.FragmentManagerImpl.moveToState(FragmentManager.java:1460)
at androidx.fragment.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManager.java:1784)
at androidx.fragment.app.FragmentManagerImpl.moveToState(FragmentManager.java:1852)
at androidx.fragment.app.BackStackRecord.executeOps(BackStackRecord.java:802)
at androidx.fragment.app.FragmentManagerImpl.executeOps(FragmentManager.java:2625)
at androidx.fragment.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2411)
at androidx.fragment.app.FragmentManagerImpl.removeRedundantOperationsAndExecute(FragmentManager.java:2366)
at androidx.fragment.app.FragmentManagerImpl.execSingleAction(FragmentManager.java:2243)
at androidx.fragment.app.BackStackRecord.commitNowAllowingStateLoss(BackStackRecord.java:654)
at androidx.fragment.app.FragmentPagerAdapter.finishUpdate(FragmentPagerAdapter.java:146)
at androidx.viewpager.widget.ViewPager.populate(ViewPager.java:1244)
at androidx.viewpager.widget.ViewPager.populate(ViewPager.java:1092)
at androidx.viewpager.widget.ViewPager.onMeasure(ViewPager.java:1622)
at android.view.View.measure(View.java:22731)
at androidx.constraintlayout.widget.ConstraintLayout.internalMeasureChildren(ConstraintLayout.java:1227)
at androidx.constraintlayout.widget.ConstraintLayout.onMeasure(ConstraintLayout.java:1572)
at android.view.View.measure(View.java:22731)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6789)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at androidx.appcompat.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:143)
at android.view.View.measure(View.java:22731)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6789)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1514)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:806)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:685)
at android.view.View.measure(View.java:22731)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6789)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at android.view.View.measure(View.java:22731)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6789)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1514)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:806)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:685)
at android.view.View.measure(View.java:22731)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6789)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
E/AndroidRuntime: at com.android.internal.policy.DecorView.onMeasure(DecorView.java:726)
at android.view.View.measure(View.java:22731)
at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2530)
at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1557)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1825)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1445)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:7013)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:921)
at android.view.Choreographer.doCallbacks(Choreographer.java:729)
at android.view.Choreographer.doFrame(Choreographer.java:664)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:907)
at android.os.Handler.handleCallback(Handler.java:790)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6524)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:451)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:888)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.RelativeLayout.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
at com.hbb20.CountryCodePicker.init(CountryCodePicker.java:222)
at com.hbb20.CountryCodePicker.(CountryCodePicker.java:156)
... 67 more
```

Start in CountryCodePicker.java at refreshArrowViewVisibility (line 478), then trace applyCustomProperty and init from the reported stack. Reproduce inflating the CountryCodePicker in the fragment and verify that the widget no longer crashes during inflation.

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