编辑：请参阅下面我的答案以获取解决方案
我有一个带有指纹登录功能的登录活动。我已经实施了BiometricPrompt对于 API 28，我使用FingerprintManagerCompat对于 API 23-27，使用任何这些版本的 Android 时一切都运行良好。但是，我正在 API 19（我的应用程序的最小Sdk）上测试我的应用程序，尽管对相关区域进行了显式 API 检查，但应用程序仍然因错误而崩溃
Unable to resolve superclass of Lcom/example/myapp/LoginActivity$BiometricCallback
and
Could not find class 'android.security.keystore.KeyGenParameterSpec$Builder', referenced from method com.example.myapp.LoginActivity.generateKey
有没有办法让我的登录活动能够使用低于 23 的 API？我究竟做错了什么？这是我的代码...
登录活动.java
public class LoginActivity extends AppCompatActivity {
//Fingerprint authorization
private final String KEY_NAME = "FingerPrintKey";
FingerprintManagerCompat fingerprintManager;
KeyStore keyStore;
KeyGenerator keyGenerator;
Cipher cipher;
FingerprintManagerCompat.CryptoObject cryptoObject;
SecretKey key;
@RequiresApi(api = 23)
private BiometricDialog mBioDialog;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
// Checking shared preferences to see if fingerprint sign in is enabled
if (bioEnabled) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
showBioMetricDialog();
}
}
}
// Method to show the dialog prompting for fingerprint
@RequiresApi(api = 23)
private void showBioMetricDialog() {
//Android P uses Biometric Prompt
if (Build.VERSION.SDK_INT >= 28) {
BiometricCallback biometricCallback = new BiometricCallback();
displayBiometricPrompt(biometricCallback);
//Older versions use Android's Keystore
} else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
fingerprintManager = FingerprintManagerCompat.from(this);
if (fingerprintManager.isHardwareDetected()
&& fingerprintManager.hasEnrolledFingerprints()) {
generateKey();
if (initCipher()) {
cryptoObject = new FingerprintManagerCompat.CryptoObject(cipher);
FingerPrintCallback callback = new FingerPrintCallback();
fingerprintManager.authenticate(cryptoObject, 0,
new android.support.v4.os.CancellationSignal(),
callback, null);
mBioDialog = new BiometricDialog(this, callback);
mBioDialog.setTitle(getString(R.string.bio_dialog_title));
mBioDialog.setSubtitle(getString(R.string.bio_dialog_subtitle));
mBioDialog.setDescription(getString(R.string.bio_dialog_finger_desc));
mBioDialog.setNegativeButtonText(getString(R.string.bio_dialog_negative));
mBioDialog.show();
}
}
}
}
@RequiresApi(api = Build.VERSION_CODES.M)
private void generateKey() {
try {
keyStore = KeyStore.getInstance("AndroidKeyStore");
keyStore.load(null);
keyGenerator = KeyGenerator.getInstance(
KeyProperties.KEY_ALGORITHM_AES, "AndroidKeyStore");
keyGenerator.init(new KeyGenParameterSpec.Builder(KEY_NAME, KeyProperties.PURPOSE_ENCRYPT | KeyProperties.PURPOSE_DECRYPT)
.setBlockModes(KeyProperties.BLOCK_MODE_CBC)
.setUserAuthenticationRequired(true)
.setEncryptionPaddings(KeyProperties.ENCRYPTION_PADDING_PKCS7)
.build());
keyGenerator.generateKey();
} catch (KeyStoreException
| NoSuchAlgorithmException
| NoSuchProviderException
| InvalidAlgorithmParameterException
| CertificateException
| IOException e) {
e.printStackTrace();
}
}
@RequiresApi(api = Build.VERSION_CODES.M)
private boolean initCipher() {
try {
cipher = Cipher.getInstance(KeyProperties.KEY_ALGORITHM_AES + "/"
+ KeyProperties.BLOCK_MODE_CBC + "/" + KeyProperties.ENCRYPTION_PADDING_PKCS7);
} catch (NoSuchAlgorithmException
| NoSuchPaddingException e) {
throw new RuntimeException("Failed to get Cipher", e);
}
try {
keyStore.load(null);
key = (SecretKey) keyStore.getKey(KEY_NAME, null);
cipher.init(Cipher.ENCRYPT_MODE, key);
return true;
} catch (KeyPermanentlyInvalidatedException e) {
return false;
} catch (KeyStoreException | CertificateException
| UnrecoverableKeyException | IOException
| NoSuchAlgorithmException | InvalidKeyException e) {
throw new RuntimeException("Failed to init Cipher", e);
}
}
@Override
protected void onDestroy() {
super.onDestroy();
if (Build.VERSION.SDK_INT >= 23) {
if (mBioDialog != null && mBioDialog.isShowing())
mBioDialog.cancel();
}
}
@RequiresApi(api = 28)
private void displayBiometricPrompt(final BiometricCallback callback) {
CancellationSignal cancellationSignal = new CancellationSignal();
cancellationSignal.setOnCancelListener(new CancellationSignal.OnCancelListener() {
@Override
public void onCancel() {
Toast.makeText(LoginActivity.this, "Cancelled", Toast.LENGTH_SHORT).show();
}
});
new BiometricPrompt.Builder(this)
.setTitle(getString(R.string.bio_dialog_title))
.setSubtitle(getString(R.string.bio_dialog_subtitle))
.setDescription(getString(R.string.bio_dialog_desc))
.setNegativeButton(getString(R.string.bio_dialog_negative), this.getMainExecutor(), new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
callback.onAuthenticationCancelled();
}
}).build().authenticate(cancellationSignal, this.getMainExecutor(), callback);
}
private void bioEnabledLogin() {
// Fetch login credentials from shared prefs and do a loginTask
}
// Inner class for Biometric Authentication callbacks
@RequiresApi(api = Build.VERSION_CODES.P)
public class BiometricCallback extends android.hardware.biometrics.BiometricPrompt.AuthenticationCallback {
@Override
public void onAuthenticationSucceeded(android.hardware.biometrics.BiometricPrompt.AuthenticationResult result) {
super.onAuthenticationSucceeded(result);
bioEnabledLogin();
}
// The rest of the callback methods here (they don't currently do anything)
}
// Inner class for FingerPrintManager Authentication callbacks
@RequiresApi(api = Build.VERSION_CODES.M)
public class FingerPrintCallback extends FingerprintManagerCompat.AuthenticationCallback {
FingerPrintCallback() {
super();
}
@Override
public void onAuthenticationSucceeded(FingerprintManagerCompat.AuthenticationResult result) {
super.onAuthenticationSucceeded(result);
mBioDialog.dismiss();
bioEnabledLogin();
}
}
}
这是 logcat 的相关部分：
09:48:01.480 15048 15048 W dalvikvm: Unable to resolve superclass of Lcom/example/myapp/LoginActivity$BiometricCallback; (300)
10-19 09:48:01.480 15048 15048 W dalvikvm: Link of class 'Lcom/example/myapp/LoginActivity$BiometricCallback;' failed
10-19 09:48:01.480 825 1043 V SmartFaceService - 3rd party pause: onReceive [android.intent.action.ACTIVITY_STATE/com.example.myapp/create]
10-19 09:48:01.490 15048 15048 E dalvikvm: Could not find class 'android.hardware.biometrics.BiometricPrompt$Builder', referenced from method com.example.myapp.LoginActivity.displayBiometricPrompt
10-19 09:48:01.490 15048 15048 W dalvikvm: VFY: unable to resolve new-instance 302 (Landroid/hardware/biometrics/BiometricPrompt$Builder;) in Lcom/example/myapp/LoginActivity;
10-19 09:48:01.490 15048 15048 D dalvikvm: VFY: replacing opcode 0x22 at 0x000d
10-19 09:48:01.490 15048 15048 E dalvikvm: Could not find class 'android.security.keystore.KeyGenParameterSpec$Builder', referenced from method com.example.myapp.LoginActivity.generateKey
10-19 09:48:01.490 15048 15048 W dalvikvm: VFY: unable to resolve new-instance 430 (Landroid/security/keystore/KeyGenParameterSpec$Builder;) in Lcom/example/myapp/LoginActivity;
10-19 09:48:01.490 15048 15048 D dalvikvm: VFY: replacing opcode 0x22 at 0x001a
10-19 09:48:01.490 15048 15048 W dalvikvm: VFY: unable to resolve exception class 432 (Landroid/security/keystore/KeyPermanentlyInvalidatedException;)
10-19 09:48:01.490 15048 15048 W dalvikvm: VFY: unable to find exception handler at addr 0x2d
10-19 09:48:01.490 15048 15048 W dalvikvm: VFY: rejected Lcom/example/myapp/LoginActivity;.initCipher ()Z
10-19 09:48:01.490 15048 15048 W dalvikvm: VFY: rejecting opcode 0x0d at 0x002d
10-19 09:48:01.490 15048 15048 W dalvikvm: VFY: rejected Lcom/example/myapp/LoginActivity;.initCipher ()Z
10-19 09:48:01.490 15048 15048 W dalvikvm: Verifier rejected class Lcom/example/myapp/LoginActivity;
10-19 09:48:01.490 15048 15048 W dalvikvm: Class init failed in newInstance call (Lcom/example/myapp/LoginActivity;)
10-19 09:48:01.490 15048 15048 D AndroidRuntime: Shutting down VM
10-19 09:48:01.490 15048 15048 W dalvikvm: threadid=1: thread exiting with uncaught exception (group=0x417d3da0)
10-19 09:48:01.490 15048 15048 E AndroidRuntime: FATAL EXCEPTION: main
10-19 09:48:01.490 15048 15048 E AndroidRuntime: Process: com.example.myapp, PID: 15048
10-19 09:48:01.490 15048 15048 E AndroidRuntime: java.lang.VerifyError: com/example/myapp/LoginActivity
10-19 09:48:01.490 15048 15048 E AndroidRuntime: at java.lang.Class.newInstanceImpl(Native Method)
10-19 09:48:01.490 15048 15048 E AndroidRuntime: at java.lang.Class.newInstance(Class.java:1208)
10-19 09:48:01.490 15048 15048 E AndroidRuntime: at android.app.Instrumentation.newActivity(Instrumentation.java:1079)
10-19 09:48:01.490 15048 15048 E AndroidRuntime: at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2199)
10-19 09:48:01.490 15048 15048 E AndroidRuntime: at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2340)
10-19 09:48:01.490 15048 15048 E AndroidRuntime: at android.app.ActivityThread.access$800(ActivityThread.java:157)
10-19 09:48:01.490 15048 15048 E AndroidRuntime: at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1247)
10-19 09:48:01.490 15048 15048 E AndroidRuntime: at android.os.Handler.dispatchMessage(Handler.java:102)
10-19 09:48:01.490 15048 15048 E AndroidRuntime: at android.os.Looper.loop(Looper.java:157)
10-19 09:48:01.490 15048 15048 E AndroidRuntime: at android.app.ActivityThread.main(ActivityThread.java:5293)
10-19 09:48:01.490 15048 15048 E AndroidRuntime: at java.lang.reflect.Method.invokeNative(Native Method)
10-19 09:48:01.490 15048 15048 E AndroidRuntime: at java.lang.reflect.Method.invoke(Method.java:515)
10-19 09:48:01.490 15048 15048 E AndroidRuntime: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1265)
10-19 09:48:01.490 15048 15048 E AndroidRuntime: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081)
10-19 09:48:01.490 15048 15048 E AndroidRuntime: at dalvik.system.NativeStart.main(Native Method)
我尝试对流程中使用的每个变量的每个声明进行显式 API 检查，但这也不起作用。有任何想法吗？
