Fingerprint API 如何知道它已被调用？

Question

我正在尝试学习如何实现指纹 API。

在其中一个指纹指南中，它给了我一个代码

@RequiresApi(api = Build.VERSION_CODES.P)
public class BiometricCallbackV28 extends BiometricPrompt.AuthenticationCallback {

    private BiometricCallback biometricCallback;
    public BiometricCallbackV28(BiometricCallback biometricCallback) {
        this.biometricCallback = biometricCallback;
    }


    @Override
    public void onAuthenticationSucceeded(BiometricPrompt.AuthenticationResult result) {
        super.onAuthenticationSucceeded(result);
        biometricCallback.onAuthenticationSuccessful();
    }


    @Override
    public void onAuthenticationHelp(int helpCode, CharSequence helpString) {
        super.onAuthenticationHelp(helpCode, helpString);
        biometricCallback.onAuthenticationHelp(helpCode, helpString);
    }


    @Override
    public void onAuthenticationError(int errorCode, CharSequence errString) {
        super.onAuthenticationError(errorCode, errString);
        biometricCallback.onAuthenticationError(errorCode, errString);
    }


    @Override
    public void onAuthenticationFailed() {
        super.onAuthenticationFailed();
        biometricCallback.onAuthenticationFailed();
    }
}

但是不应该先测试一下认证是否通过然后调用onAuthenticationSucceeded吗？我没有看到任何调用 public void onAuthenticationSucceeded 的地方。它如何知道指纹匹配？谁调用该方法？

Answer 1

But shouldn't there be a test whether the authentication passed

系统通过扫描指纹与用户登记的指纹进行比对，判断是否通过认证

I don't see anywhere that calls public void onAuthenticationSucceeded

框架根据生物识别硬件的结果调用所有这些回调方法。

Fingerprint API 如何知道它已被调用？

How does Fingerprint API know it's been called?

android

android-fingerprint-api