android NFC读取UID

1.在清单文件中添加所需要的权限

<uses-sdk android:minSdkVersion="8" /> <uses-permission android:name="android.permission.NFC" /> <uses-feature android:name="android.hardware.nfc"

2.在清单文件指定的Activity标签中添加过滤器

<intent-filter> <action android:name="android.nfc.action.TECH_DISCOVERED" /> </intent-filter> <meta-data android:name="android.nfc.action.TECH_DISCOVERED" android:resource="@xml/nfc_tech_filter" /> <intent-filter> <action android:name="android.nfc.action.TAG_DISCOVERED" /> <category android:name="android.intent.category.DEFAULT" /> </intent-filter>

3.在res目录下新建目录xml,在xml目录下新建nfc_tech_filter.xml资源文件

<?xml version="1.0" encoding="utf-8"?> <resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2"> <tech-list> <tech>android.nfc.tech.IsoDep</tech> </tech-list> <tech-list> <tech>android.nfc.tech.NfcV</tech> </tech-list> <tech-list> <tech>android.nfc.tech.NfcA</tech> </tech-list> <tech-list> <tech>android.nfc.tech.NfcC</tech> </tech-list> <tech-list> <tech>android.nfc.tech.NfcF</tech> </tech-list> </resources>

4.具体代码MainActivity

package com.etouse.nfcscanuid; import android.app.PendingIntent; import android.content.Intent; import android.nfc.NfcAdapter; import android.nfc.Tag; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.widget.TextView; import android.widget.Toast; public class MainActivity extends AppCompatActivity { private NfcAdapter nfcAdapter; private PendingIntent pendingIntent; private TextView tvUid; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); tvUid = (TextView) findViewById(R.id.tv_uid); nfcAdapter = NfcAdapter.getDefaultAdapter(this); pendingIntent = PendingIntent.getActivity(this, 0, new Intent(this, getClass()).addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP), 0); if (nfcAdapter == null) { Toast.makeText(MainActivity.this,"设备不支持NFC",Toast.LENGTH_LONG).show(); return; } if (nfcAdapter!=null&&!nfcAdapter.isEnabled()) { Toast.makeText(MainActivity.this,"请在系统设置中先启用NFC功能",Toast.LENGTH_LONG).show(); return; } onNewIntent(getIntent()); } @Override protected void onNewIntent(Intent intent) { super.onNewIntent(intent); resolveIntent(intent); } void resolveIntent(Intent intent) { Tag tag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG); if (tag != null) { processTag(intent); } } public void processTag(Intent intent) {//处理tag String uid = ""; Tag tagFromIntent = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG); // str+="Tech List:"+tagFromIntent.getTechList()[0]+"\n";//打印卡的技术列表 byte[] aa = tagFromIntent.getId(); uid += bytesToHexString(aa);//获取卡的UID tvUid.setText(uid); } //字符序列转换为16进制字符串 private String bytesToHexString(byte[] src) { StringBuilder stringBuilder = new StringBuilder("0x"); if (src == null || src.length <= 0) { return null; } char[] buffer = new char[2]; for (int i = 0; i < src.length; i++) { buffer[0] = Character.forDigit((src[i] >>> 4) & 0x0F, 16); buffer[1] = Character.forDigit(src[i] & 0x0F, 16); stringBuilder.append(buffer); } return stringBuilder.toString(); } @Override protected void onPause() { super.onPause(); if (nfcAdapter != null) nfcAdapter.disableForegroundDispatch(this); } @Override protected void onResume() { super.onResume(); if (nfcAdapter != null) nfcAdapter.enableForegroundDispatch(this, pendingIntent, null, null); } }

5.布局中代码activity_main

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:id="@+id/activity_main" android:layout_width="match_parent" android:layout_height="match_parent" android:background="#ffffff" android:orientation="vertical" tools:context="com.etouse.nfcscanuid.MainActivity"> <ImageView android:layout_width="match_parent" android:background="@mipmap/nfcbg" android:layout_height="100dp" /> <TextView android:layout_width="match_parent" android:text="读取到的标签" android:layout_height="wrap_content" /> <TextView android:id="@+id/tv_uid" android:layout_width="match_parent" android:layout_height="wrap_content"/> </LinearLayout>