如何在手机有或没有指纹按钮上的文字说明了什么？

Question

如何检查设备是否有指纹传感器，如果没有，我怎么能证明它不？

我有这样的代码，它工作得很好上没有指纹传感器的手机，但在指纹传感器的手机不能正常工作。该文本将继续表明，手机有没有指纹。我怎样才能解决这个问题？

FingerprintManagerCompat fingerprintManagerCompat = FingerprintManagerCompat.from(getApplicationContext());
if (!fingerprintManagerCompat.isHardwareDetected()) {
    // O dispositivo não suporta a autenticação de impressão digital
    BtnActionFingerprint.setEnabled(false);
    BtnActionFingerprint.setText(R.string.button_title_fingerprint_not_supported);
} else
    if (!fingerprintManagerCompat.hasEnrolledFingerprints()) {
        // O usuário não registrou nenhuma impressão digital para autenticar com
        BtnActionFingerprint.setEnabled(false);
        BtnActionFingerprint.setText(R.string.button_title_fingerprint_supported_but_unavaliable);
    } else {
        // Tudo está pronto para a autenticação de impressão digital 
        BtnActionFingerprint.setEnabled(true);
        BtnActionFingerprint.setText(R.string.button_title_fingerprint_supported);
    }

Answer 1

只要你达到这样做的：

 try {
      Button btn=(Button)findViewbyId(R.id.btn);
        FingerprintManagerCompat fingerprintManagerCompat = FingerprintManagerCompat.from(MainActivity.this);
        if (!fingerprintManagerCompat.isHardwareDetected()) {
            // Device doesn't support fingerprint authentication
            Toast.makeText(this, "device not support", Toast.LENGTH_SHORT).show();
            btn.setText("Device not supported");
        } else if (!fingerprintManagerCompat.hasEnrolledFingerprints()) {
            // User hasn't enrolled any fingerprints to authenticate with
            Toast.makeText(this, "not enrolled", Toast.LENGTH_SHORT).show();
            btn.setText("Device not Enrolled");
        } else {
            Toast.makeText(this, "ready to use fingerPrint", Toast.LENGTH_SHORT).show();
            // Everything is ready for fingerprint authentication
         btn.setText("Ready to use fingerprint");
        }
    }catch (Exception e){
        e.printStackTrace();
        Log.e("130",">>>"+e+"<<<<<");
    }

---

• 这里是一个清除你的所有疑虑截图

Answer 2

也许你在清单错过权限：

<uses-permission
    android:name="android.permission.USE_FINGERPRINT" />