Android指纹解锁方法解析

我先说说这两种的方式的不同之处吧
第一种:
在调动成功之后 不会让你指纹解锁 而是调转到当初你设置指纹解锁时的 手势解锁页面
第二种:
在调动成功之后，是进行指纹解锁 不调转 你直接把手指放到金属感应环 上面进行指纹验证
大家可以根据需求 自行选择

ok 那就亮代码了

第一种:
xml 布局: 一个 文本显示 一个按钮（不解释）

MainActivity.java源码

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", Toast.LENGTH_SHORT).show();
   return false;
 }
 Log(TAG, "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", Toast.LENGTH_SHORT).show();
   return false;
 }
 Log(TAG, "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, Manifest.permission.USE_FINGERPRINT) != PackageManager.PERMISSION_GRANTED) {
   Toast.makeText(this, "没有指纹识别权限", Toast.LENGTH_SHORT).show();
   return;
 }
 manager.authenticate(cryptoObject, mCancellationSignal, 0, 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);
}
}

===================================

第二种:
1：xml: 布局 一个文本提示 两个按钮（1: 开始识别 2:取消识别）
2: 咱们将业务操作放到一个FingerprintController 类里面

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, 0, 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();

}
}

3:在 main中 实现 FingerprintController.FingerAuthListener这个 回调接口

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);
}