我正在开发一个使用 IsoDep Tag Tech 向启用 NFC 的卡发出 APDU 命令的应用程序。
更新：所以下面看到的问题似乎与我正在使用的卡的功率要求有关，当我使用具有较低功率要求的不同卡时，以下症状不会经常发生。
我已经明确地遵循了文档并成功地实现了该协议。然而，在我的代码控制范围之外的 NFC 低级库中，我遇到了一些问题。
我已经实现了以下内容：
- 待定 Intent 的前台调度。
- Intent 具有 IsoDep.class 和操作的技术过滤器：
- ACTION_TAG_DISCOVERED
- 一旦 I 然后从 Intent Extra Issue APDU 命令中提取标签并处理响应
问题是我注意到了几件事：
在 Nexus S 上，卡的位置取决于成功的通信流程，如果它不在最佳位置，我将收到 IOException看到以下异常（见下文）我想知道是否有其他人看到这些问题？在我的 onResume 方法中，我没有任何逻辑来防止多次调用该方法的 NFCAdapter 实例：enableForegroundDispatch，我应该这样做。
提前感谢您的帮助。
示例异常 1
06-16 12:08:43.351: ERROR/NFC(661): NFC service dead - attempting to recover
06-16 12:08:43.351: ERROR/NFC(661): android.os.DeadObjectException
06-16 12:08:43.351: ERROR/NFC(661): at android.os.BinderProxy.transact(Native Method)
06-16 12:08:43.351: ERROR/NFC(661): at android.nfc.INfcAdapter$Stub$Proxy.enableForegroundDispatch(INfcAdapter.java:528)
06-16 12:08:43.351: ERROR/NFC(661): at android.nfc.NfcAdapter.enableForegroundDispatch(NfcAdapter.java:494)
06-16 12:08:43.351: ERROR/NFC(661): at myClass.onResume(MyClass.java:406)
06-16 12:08:43.351: ERROR/NFC(661): at android.app.Instrumentation.callActivityOnResume(Instrumentation.java:1150)
06-16 12:08:43.351: ERROR/NFC(661): at android.app.Activity.performResume(Activity.java:3832)
06-16 12:08:43.351: ERROR/NFC(661): at android.app.ActivityThread.performResumeActivity(ActivityThread.java:2110)
06-16 12:08:43.351: ERROR/NFC(661): at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:2135)
06-16 12:08:43.351: ERROR/NFC(661): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1668)
06-16 12:08:43.351: ERROR/NFC(661): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
06-16 12:08:43.351: ERROR/NFC(661): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
06-16 12:08:43.351: ERROR/NFC(661): at android.os.Handler.dispatchMessage(Handler.java:99)
06-16 12:08:43.351: ERROR/NFC(661): at android.os.Looper.loop(Looper.java:130)
06-16 12:08:43.351: ERROR/NFC(661): at android.app.ActivityThread.main(ActivityThread.java:3683)
06-16 12:08:43.351: ERROR/NFC(661): at java.lang.reflect.Method.invokeNative(Native Method)
06-16 12:08:43.351: ERROR/NFC(661): at java.lang.reflect.Method.invoke(Method.java:507)
06-16 12:08:43.351: ERROR/NFC(661): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
06-16 12:08:43.351: ERROR/NFC(661): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
06-16 12:08:43.351: ERROR/NFC(661): at dalvik.system.NativeStart.main(Native Method)
示例异常 2
06-16 12:08:18.316: ERROR/MyClass(661): IOException in APDU commands: transceive failed
06-16 12:08:18.316: WARN/System.err(661): java.io.IOException: transceive failed
06-16 12:08:18.324: WARN/System.err(661): at android.nfc.tech.BasicTagTechnology.transceive(BasicTagTechnology.java:144)
06-16 12:08:18.324: WARN/System.err(661): at android.nfc.tech.IsoDep.transceive(IsoDep.java:159)
06-16 12:08:18.328: WARN/System.err(661): at myClass.handleTagRead(MyClass.java:117)
06-16 12:08:18.328: WARN/System.err(661): at myClass.onNewIntent(MyClass.java:84)
06-16 12:08:18.332: WARN/System.err(661): at android.app.Instrumentation.callActivityOnNewIntent(Instrumentation.java:1119)
06-16 12:08:18.332: WARN/System.err(661): at android.app.ActivityThread.deliverNewIntents(ActivityThread.java:1722)
06-16 12:08:18.335: WARN/System.err(661): at android.app.ActivityThread.performNewIntents(ActivityThread.java:1734)
06-16 12:08:18.335: WARN/System.err(661): at android.app.ActivityThread.handleNewIntent(ActivityThread.java:1742)
06-16 12:08:18.339: WARN/System.err(661): at android.app.ActivityThread.access$2300(ActivityThread.java:117)
06-16 12:08:18.343: WARN/System.err(661): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:978)
06-16 12:08:18.343: WARN/System.err(661): at android.os.Handler.dispatchMessage(Handler.java:99)
06-16 12:08:18.347: WARN/System.err(661): at android.os.Looper.loop(Looper.java:130)
06-16 12:08:18.347: WARN/System.err(661): at android.app.ActivityThread.main(ActivityThread.java:3683)
06-16 12:08:18.351: WARN/System.err(661): at java.lang.reflect.Method.invokeNative(Native Method)
06-16 12:08:18.351: WARN/System.err(661): at java.lang.reflect.Method.invoke(Method.java:507)
06-16 12:08:18.355: WARN/System.err(661): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
06-16 12:08:18.355: WARN/System.err(661): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
06-16 12:08:18.359: WARN/System.err(661): at dalvik.system.NativeStart.main(Native Method)
06-16 12:08:18.359: DEBUG/MyClass(661): Setting up for ForegroundDispatch for NFC ISO DEP
06-16 12:08:18.492: DEBUG/NativeNfcTag(871): Tag lost, restarting polling loop
06-16 12:08:19.269: WARN/NfcService(871): Failed to connect to tag
06-16 12:08:23.980: ERROR/NFC JNI(871): phLibNfc_RemoteDev_Connect(RW) returned 0x00ff[NFCSTATUS_FAILED]
06-16 12:08:23.980: WARN/NfcService(871): Failed to connect to tag
06-16 12:08:23.980: ERROR/NFC JNI(871): doDisconnect() - Target already disconnected
示例例外 3
06-16 12:08:15.468: DEBUG/MyClass(661): Recieved a TAG
06-16 12:08:15.468: DEBUG/MyClass(661): Supported Technology of for recieve d tag: android.nfc.tech.IsoDep
06-16 12:08:15.468: DEBUG/MyClass(661): Supported Technology of for recieved tag: android.nfc.tech.NfcA
06-16 12:08:15.468: DEBUG/MyClass(661): Supported Technology of for recieved tag: android.nfc.tech.MifareClassic
06-16 12:08:15.484: ERROR/MyClass(661): Failed to connect to aTag Reason: null
06-16 12:08:15.484: WARN/System.err(661): java.io.IOException
06-16 12:08:15.484: WARN/System.err(661): at android.nfc.tech.BasicTagTechnology.connect(BasicTagTechnology.java:81)
06-16 12:08:15.484: WARN/System.err(661): at android.nfc.tech.IsoDep.connect(IsoDep.java:39)
06-16 12:08:15.484: WARN/System.err(661): at myClass.handleTagRead(ConfirmPaymentScreen.java:107)
06-16 12:08:15.484: WARN/System.err(661): at myClass.onNewIntent(ConfirmPaymentScreen.java:84)
06-16 12:08:15.484: WARN/System.err(661): at android.app.Instrumentation.callActivityOnNewIntent(Instrumentation.java:1119)
06-16 12:08:15.484: WARN/System.err(661): at android.app.ActivityThread.deliverNewIntents(ActivityThread.java:1722)
06-16 12:08:15.484: WARN/System.err(661): at android.app.ActivityThread.performNewIntents(ActivityThread.java:1734)
06-16 12:08:15.484: WARN/System.err(661): at android.app.ActivityThread.handleNewIntent(ActivityThread.java:1742)
06-16 12:08:15.484: WARN/System.err(661): at android.app.ActivityThread.access$2300(ActivityThread.java:117)
06-16 12:08:15.484: WARN/System.err(661): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:978)
06-16 12:08:15.484: WARN/System.err(661): at android.os.Handler.dispatchMessage(Handler.java:99)
06-16 12:08:15.484: WARN/System.err(661): at android.os.Looper.loop(Looper.java:130)
06-16 12:08:15.484: WARN/System.err(661): at android.app.ActivityThread.main(ActivityThread.java:3683)
06-16 12:08:15.484: WARN/System.err(661): at java.lang.reflect.Method.invokeNative(Native Method)
06-16 12:08:15.484: WARN/System.err(661): at java.lang.reflect.Method.invoke(Method.java:507)
06-16 12:08:15.484: WARN/System.err(661): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
06-16 12:08:15.484: WARN/System.err(661): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
06-16 12:08:15.484: WARN/System.err(661): at dalvik.system.NativeStart.main(Native Method)
06-16 12:08:15.484: DEBUG/MyClass(661): Failed to connect to tag
06-16 12:08:15.484: DEBUG/MyClass(661): Setting up for ForegroundDispatch for NFC ISO DEP
06-16 12:08:15.609: ERROR/NFC JNI(871): phLibNfc_RemoteDev_CheckPresence() returned 0x0095[NFCSTATUS_INVALID_HANDLE]
06-16 12:08:15.609: DEBUG/NativeNfcTag(871): Tag lost, restarting polling loop
06-16 12:08:15.609: ERROR/NFC JNI(871): phLibNfc_RemoteDev_Disconnect(294f58) returned 0x0095[NFCSTATUS_INVALID_HANDLE]