About the BiometricPrompt.authenticate()

Question

在Android开发者的参考资料中，我发现了这句话：

此调用预热生物特征硬件，显示提供的系统对话框，并开始扫描生物特征。

此调用验证用户是否在智能手机上有指纹？如果没有，我如何验证？

private void setLoginFingerprint() {
final Executor executor = Executors.newSingleThreadExecutor();
final BiometricPrompt biometricPrompt = new BiometricPrompt.Builder(this)
.setTitle("")
.setSubtitle("")
.setDescription("")
.setNegativeButton("Cancel", executor, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
finish();
}
}).build();

loginFingerprint = findViewById(R.id.ll_leitor_digital);
loginFingerprint.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
biometricPrompt.authenticate(new CancellationSignal(), executor, new BiometricPrompt.AuthenticationCallback() {
@Override
public void onAuthenticationError(int errorCode, CharSequence errString) {
super.onAuthenticationError(errorCode, errString);
LoginActivity.this.runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(LoginActivity.this, "Error!", Toast.LENGTH_SHORT).show();
}
});
}
@Override
public void onAuthenticationSucceeded(BiometricPrompt.AuthenticationResult result) {
super.onAuthenticationSucceeded(result);
LoginActivity.this.runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(LoginActivity.this, "Auth!", Toast.LENGTH_SHORT).show();
}
});
}
@Override
public void onAuthenticationFailed() {
super.onAuthenticationFailed();
LoginActivity.this.runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(LoginActivity.this, "Error", Toast.LENGTH_SHORT).show();
}
});
}
});
}
});
}

Answer 1

在这种情况下，它将给出BIOMETRIC_ERROR_HW_NOT_PRESENT错误。如果发生这种情况，请使用KeyguardManager。然后，他们可以使用PIN或他们设置的任何身份验证方法进行身份验证。要处理此问题，请在onAuthenticationError中检查错误代码是否为BIOMETRIC_ERROR_HW_NOT_PRESENT。如果是，请使用KeyguardManager。