指纹验证 为什么写在Service中就拿不到返回值

Question

if (fingerprintManager.isHardwareDetected()) {

        //判断屏幕锁是否正常。想要使用指纹识别的话，必须首先使能屏幕锁才行，
        KeyguardManager keyguardManager = (KeyguardManager) context.getSystemService(Context.KEYGUARD_SERVICE);

        // this device is secure..
        /* Return whether the keyguard is secured by a PIN, pattern or password or a SIM card
        * is currently locked.*/


        //            if (keyguardManager.isKeyguardSecure()) {

        //6.0中，普通app要想使用指纹识别功能的话，用户必须首先在setting中注册至少一个指纹才行，否则是不能使用的
        if (fingerprintManager.hasEnrolledFingerprints()) {

            // start fingerprint auth here.
            try {
                //                    CryptoObjectHelper cryptoObjectHelper = new CryptoObjectHelper();

                // 创建一个取消信号，初始化时是非取消状态
                if (cancellationSignal == null) {
                    cancellationSignal = new CancellationSignal();

                }

                if (cancellationSignal.isCanceled()) {
                    cancellationSignal = new CancellationSignal();
                }

                //指纹认证回调接口
                myAuthCallback = new MyAuthCallback(context, handler);

                //一直扫描指纹硬件。

                fingerprintManager.authenticate(null, cancellationSignal, 0, myAuthCallback, null);

            } catch (Exception e) {

            }

        }


以上是指纹验证的主要代码，写在Activity中是可以正常验证的，写在Service却拿不到返回值，不知道是什么原因？

Answer 1

http://blog.csdn.net/zhangdong305/article/details/52438050