customTab.onNavigationEvent issue in production

[arlee17]

Hello,

Users navigate to a custom tab to pay in my e-commerce app, so we have implemented a CustomBrowserTabDecisionHandler.
We have many errors in this implementation. Here is my code:

  override val name: String = "custom-browser-tab"
  private var customTabsSession: CustomTabsSession? = null
  private var customTabsConnection: CustomTabsServiceConnection? = null

  override fun matches(
    location: String,
    configuration: NavigatorConfiguration
  ): Boolean {
    return configuration.startLocation.toUri().host != location.toUri().host
  }

  @SuppressLint("ResourceAsColor")
  override fun handle(
    location: String,
    configuration: NavigatorConfiguration,
    activity: HotwireActivity
  ): Router.Decision {
    if (customTabsConnection != null) {
      try {
        activity.unbindService(customTabsConnection!!)
      } catch (e: IllegalArgumentException) {
        Log.w("CUSTOM_TAB", "unbindService failed: ${e.message}")
      }
      customTabsConnection = null
    }

    customTabsConnection = object : CustomTabsServiceConnection() {
      val customTabsCallback = object : CustomTabsCallback() {
        override fun onNavigationEvent(navigationEvent: Int, extras: Bundle?) {
          when (navigationEvent) {
            TAB_HIDDEN -> {
              try {
                activity.unbindService(customTabsConnection!!)
              } catch (e: IllegalArgumentException) {
                Log.w("CUSTOM_TAB", "unbindService failed: ${e.message}")
              }

              customTabsConnection = null

              MainActivity.instance.navigateTo(getBaseUrl())
              activity.delegate.resetSessions()
            }

            else -> Log.d("NAVIGATION_EVENT", "Unknown event")
          }
        }
      }

      override fun onServiceDisconnected(name: ComponentName?) {
        Log.d("CUSTOM_TAB", "Service Disconnected")
      }

      override fun onCustomTabsServiceConnected(name: ComponentName, client: CustomTabsClient) {
        customTabsSession = client.newSession(customTabsCallback)
        client.warmup(0L)
        val color = R.color.colorPrimaryDark
        val colorParams = CustomTabColorSchemeParams.Builder()
          .build()

        CustomTabsIntent.Builder(customTabsSession)
          .setShowTitle(false)
          .launchUrl(activity, location.toUri())
      }
    }
    CustomTabsClient.bindCustomTabsService(
      activity,
      "com.android.chrome",
      customTabsConnection!!
    )
    return Router.Decision.CANCEL
  }

MainActivity.nativateTo():

  fun navigateTo(destination: String) {
    navigator?.route(destination)
    selectBottomNavItemByUrl(destination)
  }

Log from Google Play Console:

Exception java.lang.NullPointerException:
  at com.myapp.handlers.CustomBrowserTabDecisionHandler$handle$1$customTabsCallback$1.onNavigationEvent (CustomBrowserTabDecisionHandler.kt:68)
  at androidx.browser.customtabs.CustomTabsClient$3$1.run (CustomTabsClient.java:493)
  at android.os.Handler.handleCallback (Handler.java:959)
  at android.os.Handler.dispatchMessage (Handler.java:100)
  at android.os.Looper.loopOnce (Looper.java:249)
  at android.os.Looper.loop (Looper.java:337)
  at android.app.ActivityThread.main (ActivityThread.java:9511)
  at java.lang.reflect.Method.invoke
  at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run (RuntimeInit.java:636)
  at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:1005)

Users can close the custom tab and return to the app for various reasons, such as choosing another payment method.
Any help for solving this?

Thanks