88.9 Adding the CancellationSignal

Once initiated, the biometric authentication process is performed independently of the app. To provide the app with a way to cancel the operation, an instance of the CancellationSignal class is created and passed to the biometric authentication process. This CancellationSignal instance can then be used to cancel the process if necessary. The cancellation signal instance may be configured with a listener which will be called when the cancellation is completed. Add a new method to the activity class to configure and return a CancellationSignal object as follows:

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import android.os.CancellationSignal

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private var cancellationSignal: CancellationSignal? = null

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private fun getCancellationSignal(): CancellationSignal {

 

    cancellationSignal = CancellationSignal()

    cancellationSignal?.setOnCancelListener {

        notifyUser...