如何使用BiometricManager或BiometricPrompt检查生物识别硬件是否可用?

Question

我正在使用BiometricPrompt类实现生物识别身份验证。

1. 在调用方法之前如何检查硬件是否可用BiometricPrompt#authenticate？
2. 如何检查是否已注册生物识别技术？

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

我目前的实现如下。

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)

Answer 1

终于修复了问题

BiometricManager类在 androidx 库中被遗漏

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

您可以检查生物识别硬件的可用性，并通过以下代码注册生物识别：

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
}
}
}