Android指纹解锁方法解析

public class MainActivity extends FragmentActivity { 
FingerprintManager manager; 
KeyguardManager mKeyManager; 
private final static int REQUEST_CODE_CONFIRM_DEVICE_CREDENTIALS = 0; 
private final static String TAG = “finger_log”;

@Override 
protected void onCreate(Bundle savedInstanceState) { 
  super.onCreate(savedInstanceState); 
  setContentView(R.layout.activity_main); 
  //1:先获取 指纹识别的的管理者 看看获取方式 是不是感觉就和数学公式一样
  （xxx管理者）=this.getSystemService（Context.xxx服务）
  manager = (FingerprintManager) this.getSystemService(Context.FINGERPRINT_SERVICE); 
  mKeyManager = (KeyguardManager) this.getSystemService(Context.KEYGUARD_SERVICE); 
// 2 初始化按钮 设置监听 
// 监听 监听 听什么 肯定是听听 这个手机有没有 指纹识别这个功能 所以 看看isFinger()

  Button btn_finger = (Button) findViewById(R.id.btn_activity_main_finger); 
  btn_finger.setOnClickListener(new View.OnClickListener() { 
    @Override 
    public void onClick(View v) { 
      if (isFinger()) { 
        Toast.makeText(MainActivity.this,"请进行指纹识别",Toast.LENGTH_LONG).show(); 
        Log(TAG,"keyi"); 
        startListening(null); 
      } 
    } 
  }); 

} 

public boolean isFinger() { 

  //android studio 上，没有这个会报错 
  if (ActivityCompat.checkSelfPermission(this,Manifest.permission.USE_FINGERPRINT) != PackageManager.PERMISSION_GRANTED) { 
    Toast.makeText(this,"没有指纹识别权限",Toast.LENGTH_SHORT).show(); 
    return false; 
  } 
  Log(TAG,"有指纹权限"); 
  //判断硬件是否支持指纹识别 
  if (!manager.isHardwareDetected()) { 
    Toast.makeText(this,"没有指纹识别模块",Toast.LENGTH_SHORT).show(); 
    return false; 
  } 
 Log(TAG,"有指纹模块"); 
  //判断 是否开启锁屏密码 

  if (!mKeyManager.isKeyguardSecure()) { 
    Toast.makeText(this,"没有开启锁屏密码","已开启锁屏密码"); 
  //判断是否有指纹录入 
  if (!manager.hasEnrolledFingerprints()) { 
    Toast.makeText(this,"没有录入指纹","已录入指纹"); 

  return true; 
} 

CancellationSignal mCancellationSignal = new CancellationSignal(); 
//回调方法 
FingerprintManager.AuthenticationCallback mSelfCancelled = new FingerprintManager.AuthenticationCallback() { 
  @Override 
  public void onAuthenticationError(int errorCode,CharSequence errString) { 
    //但多次指纹密码验证错误后，进入此方法；并且，不能短时间内调用指纹验证 
    Toast.makeText(MainActivity.this,errString,Toast.LENGTH_SHORT).show(); 
    showAuthenticationScreen(); 
  } 

  @Override 
  public void onAuthenticationHelp(int helpCode,CharSequence helpString) { 

    Toast.makeText(MainActivity.this,helpString,Toast.LENGTH_SHORT).show(); 
  } 

  @Override 
  public void onAuthenticationSucceeded(FingerprintManager.AuthenticationResult result) { 

    Toast.makeText(MainActivity.this,"指纹识别成功",Toast.LENGTH_SHORT).show(); 
  } 

  @Override 
  public void onAuthenticationFailed() { 
    Toast.makeText(MainActivity.this,"指纹识别失败",Toast.LENGTH_SHORT).show(); 
  } 
}; 


public void startListening(FingerprintManager.CryptoObject cryptoObject) { 
  //android studio 上，没有这个会报错 
  if (ActivityCompat.checkSelfPermission(this,Toast.LENGTH_SHORT).show(); 
    return; 
  } 
  manager.authenticate(cryptoObject,mCancellationSignal,mSelfCancelled,null); 


} 

/** 
 * 锁屏密码 
 */ 
private void showAuthenticationScreen() { 

  Intent intent = mKeyManager.createConfirmDeviceCredentialIntent("finger","测试指纹识别"); 
  if (intent != null) { 
    startActivityForResult(intent,REQUEST_CODE_CONFIRM_DEVICE_CREDENTIALS); 
  } 
} 

@Override 
protected void onActivityResult(int requestCode,int resultCode,Intent data) { 
  if (requestCode == REQUEST_CODE_CONFIRM_DEVICE_CREDENTIALS) { 
    // Challenge completed,proceed with using cipher 
    if (resultCode == RESULT_OK) { 
      Toast.makeText(this,"识别成功",Toast.LENGTH_SHORT).show(); 
    } else { 
      Toast.makeText(this,"识别失败",Toast.LENGTH_SHORT).show(); 
    } 
  } 
} 

private void Log(String tag,String msg) { 
  Log.d(tag,msg); 
} 
}

private static FingerprintController sSingleton = null;

private Context mContext;

private FingerprintManagerCompat manager;

private static final String TAG = "FingerprintController";
private static final String PREMISSION = "android.permission.USE_FINGERPRINT";

//成功
public static final int FINGER_SUCCESS = 0;
//硬件不支持
public static final int FINGER_ERROR_NO_HARDWARE = 1;
//没有申请权限
public static final int FINGER_ERROR_NO_PERMISSION = 2;
//用户没有赋予权限
//Protection level: normal
//指纹权限的级别是normal,理论上不需要动态权限认证
public static final int FINGER_ERROR_NO_USER_PERMISSION = 3;
//用户没有储存指纹
public static final int FINGER_ERROR_NO_FINGER = 4;

//取消指纹识别
private CancellationSignal cancellationSignal;

private FingerAuthListener mAuthListener;

public static synchronized FingerprintController getInstance(Context context) {
  if (sSingleton == null) {
    sSingleton = new FingerprintController(context);
  }
  return sSingleton;
}

public FingerprintController(Context context) {
  mContext = context;
  manager = FingerprintManagerCompat.from(this.mContext);
}

/**
 * 开始指纹识别
 * 失败次数过多后需要一定时间后才可以重新启动
 */
public void startFingerAuth() {
  if (null == cancellationSignal) {
    cancellationSignal = new CancellationSignal();
  }
  manager.authenticate(null,cancellationSignal,new FingerAuthCallBack(),null);
}

/**
 * 取消指纹识别
 */
public void cancelFingerAuth() {
  if (cancellationSignal != null) {
    cancellationSignal.cancel();
    if (mAuthListener != null)
      mAuthListener.cancel();
  }
}

/**
 * 指纹识别回调
 */
public class FingerAuthCallBack extends FingerprintManagerCompat.AuthenticationCallback {

  // 当出现错误的时候回调此函数，比如多次尝试都失败了的时候，errString是错误信息
  @Override
  public void onAuthenticationError(int errMsgId,CharSequence errString) {
// Log.d(TAG,“onAuthenticationError: ” + errString); 
if (null != mAuthListener) 
mAuthListener.error(errString.toString()); 
}

  // 当指纹验证失败的时候会回调此函数，失败之后允许多次尝试，失败次数过多会停止响应一段时间然后再停止sensor的工作
  @Override
  public void onAuthenticationFailed() {
    if (null != mAuthListener)
      mAuthListener.failure();
  }

  @Override
  public void onAuthenticationHelp(int helpMsgId,CharSequence helpString) {
    if (null != mAuthListener)

      Log.e("helpMsgId",helpMsgId+"");
      Log.e("helpString",helpString.toString());
      mAuthListener.help(helpString.toString());
  }

  // 当验证的指纹成功时会回调此函数，然后不再监听指纹sensor
  @Override
  public void onAuthenticationSucceeded(FingerprintManagerCompat.AuthenticationResult result) {

   if (null != mAuthListener)
      mAuthListener.success();

  }

}

/**
 * 检查指纹解锁是否可用
 *
 * @return 状态
 */
public int checkFingerEnable() {
  if (null == manager) {
    manager = FingerprintManagerCompat.from(mContext);
  }
  if (!isAppPermissionEnable()) {
    return FINGER_ERROR_NO_PERMISSION;
  }
  if (!manager.isHardwareDetected()) {
    return FINGER_ERROR_NO_HARDWARE;
  }
  if (!manager.hasEnrolledFingerprints()) {
    return FINGER_ERROR_NO_FINGER;
  }
  if (!isUserPermissionEnable()) {
    return FINGER_ERROR_NO_USER_PERMISSION;
  }
  return FINGER_SUCCESS;
}

/**
 * 是否声明了该权限
 */
private boolean isAppPermissionEnable() {
  PackageManager pm = mContext.getPackageManager();
  if (pm == null) {
    Log.w(TAG,"can't get packagemanager");
    return true;
  }
  try {
    return PackageManager.PERMISSION_GRANTED == pm.checkPermission(PREMISSION,mContext.getPackageName());
  } catch (Exception e) {
    Log.w(TAG,"can't checkt Permission " + e.getMessage());
    return true;
  }
}

/**
 * 是否具有动态权限,理论上不需要验证
 */
private boolean isUserPermissionEnable() {
  if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
    return PackageManager.PERMISSION_GRANTED == mContext.checkSelfPermission(Manifest.permission.USE_FINGERPRINT);
  }
  return true;
}

public void setAuthListener(FingerAuthListener authListener) {
  mAuthListener = authListener;
}

public interface FingerAuthListener {

  void success();

  void error(String error);

  void help(String msg);

  void cancel();

  void failure();

}
} 

private int code = FingerprintController.FINGER_SUCCESS;

private TextView toast;

@Override
protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_main);

 toast = (TextView) findViewById(R.id.toast);

 code = FingerprintController.getInstance(this).checkFingerEnable();
 if (code == FingerprintController.FINGER_SUCCESS) {
  FingerprintController.getInstance(this).setAuthListener(this);
  setToast("可以启动指纹识别");
 } else {
  switch (code) {
   case FingerprintController.FINGER_ERROR_NO_HARDWARE:
    setToast("该设备不支持指纹识别");
    break;
   case FingerprintController.FINGER_ERROR_NO_PERMISSION:
    setToast("当前应用没有指纹识别权限");
    break;
   case FingerprintController.FINGER_ERROR_NO_FINGER:
    setToast("当前设备没有录入指纹,请前往录入指纹");
    break;
  }
 }

}

public void start(View view) {
 if (code == FingerprintController.FINGER_SUCCESS) {
  FingerprintController.getInstance(this).startFingerAuth();
  setToast("开始指纹识别");
 }
}

public void cancel(View view) {
 if (code == FingerprintController.FINGER_SUCCESS) {
  FingerprintController.getInstance(this).cancelFingerAuth();
 }
}


@Override
public void success() {
 setToast("识别成功");
}

@Override
public void error(String error) {
 setToast(error);
}

@Override
public void help(String msg) {
 setToast(msg);
}

@Override
public void cancel() {
 setToast("取消指纹识别");
}

@Override
public void failure() {
 setToast("指纹识别失败");
}

public void setToast(String msg) {
 toast.setText("提示:" + msg);
}