Android指纹识别API初试

public class MainActivity extends AppCompatActivity implements View.OnClickListener {
 private static final String TAG = "MainActivity";
 private Button check;
 private FingerprintManagerCompat manager;

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

 check = (Button) findViewById(R.id.btn_check);

 check.setOnClickListener(this);

 // 获取一个FingerPrintManagerCompat的实例
 manager = FingerprintManagerCompat.from(this);
 }

 @Override
 public void onClick(View v) {
 switch (v.getId()) {
 case R.id.btn_check:
 /**
  * 开始验证，什么时候停止由系统来确定，如果验证成功，那么系统会关系sensor，如果失败，则允许
  * 多次尝试，如果依旧失败，则会拒绝一段时间，然后关闭sensor，过一段时候之后再重新允许尝试
  * 
  * 第四个参数为重点，需要传入一个FingerprintManagerCompat.AuthenticationCallback的子类
  * 并重写一些方法，不同的情况回调不同的函数
  */
 manager.authenticate(null, 0, null, new MyCallBack(), null);
 break;
 }
 }

 public class MyCallBack extends FingerprintManagerCompat.AuthenticationCallback {
 private static final String TAG = "MyCallBack";

 // 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);
 }

 // 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() {
 Log.d(TAG, "onAuthenticationFailed: " + "验证失败");
 }

 @Override
 public void onAuthenticationHelp(int helpMsgId, CharSequence helpString) {
 Log.d(TAG, "onAuthenticationHelp: " + helpString);
 }

 // 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) {
 Log.d(TAG, "onAuthenticationSucceeded: " + "验证成功");
 }
 }

} 

private Handler handler = new Handler() {
 @Override
 public void handleMessage(Message msg) {
 super.handleMessage(msg);
 Log.d(TAG, "handleMessage: 重启指纹模块");
 manager.authenticate(null, 0, null, new MyCallBack(), handler);
 }
}; 

@Override
public void onAuthenticationError(int errMsgId, CharSequence errString) {
 handler.sendMessageDelayed(new Message(), 1000 * 30);
 Log.d(TAG, "onAuthenticationError: " + errString);
}

@Override
public void onAuthenticationSucceeded(FingerprintManagerCompat.AuthenticationResult result) {
 handler.sendMessageDelayed(new Message(), 1000 * 30);
 Log.d(TAG, "onAuthenticationSucceeded: " + "验证成功");
}