java - 如何使用BiometricManager或BiometricPrompt检查可用的生物识别硬件？

我正在使用BiometricPrompt类实现生物特征认证。

在调用BiometricPrompt#authenticate方法之前如何检查硬件是否可用？

如何检查已注册的生物识别信息？

如何调用BiometricManager#canAuthenticate方法？
我无法在Kotlin中为BiometricManager类创建对象

我当前的实现如下。

    val executor = Executors.newSingleThreadExecutor()

    val biometricPrompt = BiometricPrompt(this, executor, object : BiometricPrompt.AuthenticationCallback() {

        override fun onAuthenticationError(errorCode: Int, errString: CharSequence) {
            super.onAuthenticationError(errorCode, errString)
            Log.d("BIOMETRIC", "$errString $errorCode")

            if (BiometricPrompt.ERROR_HW_NOT_PRESENT == errorCode || BiometricPrompt.ERROR_NO_BIOMETRICS == errorCode)
                PreferenceHandler.setBiometricAvailable(this@LockActivity, false)
            else
                PreferenceHandler.setBiometricAvailable(this@LockActivity, true)
        }

        override fun onAuthenticationSucceeded(result: BiometricPrompt.AuthenticationResult) {
            super.onAuthenticationSucceeded(result)
        }

        override fun onAuthenticationFailed() {
            super.onAuthenticationFailed()
            Log.d("BIOMETRIC", "FAILED")
        }
    })

    val promptInfo = BiometricPrompt.PromptInfo.Builder()
            .setTitle("App title")
            .setSubtitle("")
            .setDescription("Identify yourself by Biometrics")
            .setNegativeButtonText("Use Password")
            .build()

    biometricPrompt.authenticate(promptInfo)

最佳答案

最后修复

androidx库中缺少BiometricManager类

androidx.biometric:biometric:1.0.0-alpha04

将库版本更新为

androidx.biometric:biometric:1.0.0-beta01

现在您可以导入androidx.biometric.BiometricManager
您可以通过以下代码检查生物识别硬件的可用性并进行生物识别注册:

object BiometricUtil {

fun isHardwareAvailable(context: Context): Boolean{
    return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M){
        val bm = BiometricManager.from(context)
        val canAuthenticate = bm.canAuthenticate()
        !(canAuthenticate == BiometricManager.BIOMETRIC_ERROR_NO_HARDWARE || canAuthenticate == BiometricManager.BIOMETRIC_ERROR_HW_UNAVAILABLE)

    } else {
        false
    }
}

fun hasBiometricEnrolled(context: Context): Boolean {
    return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M){
        val bm = BiometricManager.from(context)
        val canAuthenticate = bm.canAuthenticate()
        (canAuthenticate == BiometricManager.BIOMETRIC_SUCCESS)

    } else {
        false
    }
}
}