Android实现读取NFC卡卡号示例

  <uses-permission android:name="android.permission.nfc" />
    <uses-feature
    android:name="android.hardware.nfc"
    android:required="true" />

      <intent-filter>
        <action android:name="android.nfc.action.tag_discovered" />
        <data android:mimetype="text/plain" />
      </intent-filter>

    //初始化nfcadapter
    mnfcadapter = nfcadapter.getdefaultadapter(this);
        // 初始化pendingintent，当有nfc设备连接上的时候，就交给当前activity处理
    pi = pendingintent.getactivity(this, 0, new intent(this, getclass())
        .addflags(intent.flag_activity_single_top), 0);

  @override
  protected void onresume() {
    super.onresume();
    mnfcadapter.enableforegrounddispatch(this, pi, null, null); //启动
  }

  @override
  protected void onnewintent(intent intent) {
    super.onnewintent(intent);
    // 当前app正在前端界面运行，这个时候有intent发送过来，那么系统就会调用onnewintent回调方法，将intent传送过来
    // 我们只需要在这里检验这个intent是否是nfc相关的intent，如果是，就调用处理方法
    if (nfcadapter.action_tag_discovered.equals(intent.getaction())) {
      processintent(intent);
    }
  }

  /**
   * parses the ndef message from the intent and prints to the textview
   */
  private void processintent(intent intent) {
    //取出封装在intent中的tag
    tag tagfromintent = intent.getparcelableextra(nfcadapter.extra_tag);
    string cardid =bytearraytohexstring(tagfromintent.getid());
  }
private string bytearraytohexstring(byte[] inarray) {
    int i, j, in;
    string[] hex = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a",
        "b", "c", "d", "e", "f" };
    string out = "";


    for (j = 0; j < inarray.length; ++j) {
      in = (int) inarray[j] & 0xff;
      i = (in >> 4) & 0x0f;
      out += hex[i];
      i = in & 0x0f;
      out += hex[i];
    }
    return out;
  }

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
  package="cn.com.jslh.zjcdprogrect">

  <uses-permission android:name="android.permission.nfc" />
  <uses-permission android:name="android.permission.internet" />

  <uses-feature
    android:name="android.hardware.nfc"
    android:required="true" />

  <application
    android:name=".common.myapplication"
    android:allowbackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:roundicon="@mipmap/ic_launcher_round"
    android:supportsrtl="true"
    android:theme="@style/apptheme">
    <activity android:name=".loginactivity">
      <intent-filter>
        <action android:name="android.intent.action.main" />

        <category android:name="android.intent.category.launcher" />
      </intent-filter>
    </activity>
    <activity android:name=".saoka.workactivity">
      <intent-filter>
        <action android:name="android.nfc.action.tag_discovered" />
        <data android:mimetype="text/plain" />
      </intent-filter>
      <!--<meta-data android:name="android.nfc.action.tech_discovered" android:resource="@xml/nfc_tech_filter" />-->
    </activity>
  </application>

</manifest>

package cn.com.jslh.zjcdprogrect.saoka;

import android.app.pendingintent;
import android.content.context;
import android.content.intent;
import android.content.intentfilter;
import android.nfc.nfcadapter;
import android.nfc.tag;
import android.os.bundle;
import android.support.v7.app.appcompatactivity;

import cn.com.jslh.zjcdprogrect.r;

public class workactivity extends appcompatactivity {

  private nfcadapter mnfcadapter;
  private pendingintent pi;
  private intentfilter tagdetected;

  @override
  protected void oncreate(bundle savedinstancestate) {
    super.oncreate(savedinstancestate);
    setcontentview(r.layout.activity_work);

    //初始化nfcadapter
    mnfcadapter = nfcadapter.getdefaultadapter(this);
    //初始化pendingintent
    // 初始化pendingintent，当有nfc设备连接上的时候，就交给当前activity处理
    pi = pendingintent.getactivity(this, 0, new intent(this, getclass())
        .addflags(intent.flag_activity_single_top), 0);
    // 新建intentfilter，使用的是第二种的过滤机制
//    tagdetected = new intentfilter(nfcadapter.action_tech_discovered);
//    tagdetected.addcategory(intent.category_default);
  }

  @override
  protected void onnewintent(intent intent) {
    super.onnewintent(intent);
    // 当前app正在前端界面运行，这个时候有intent发送过来，那么系统就会调用onnewintent回调方法，将intent传送过来
    // 我们只需要在这里检验这个intent是否是nfc相关的intent，如果是，就调用处理方法
    if (nfcadapter.action_tag_discovered.equals(intent.getaction())) {
      processintent(intent);
    }
  }

  @override
  protected void onresume() {
    super.onresume();
    mnfcadapter.enableforegrounddispatch(this, pi, null, null);
  }

  /**
   * parses the ndef message from the intent and prints to the textview
   */
  private void processintent(intent intent) {
    //取出封装在intent中的tag
    tag tagfromintent = intent.getparcelableextra(nfcadapter.extra_tag);
    string cardid =bytearraytohexstring(tagfromintent.getid());
  }

  public static void startactivity(context context){
    intent intent = new intent();
    intent.setclass(context,workactivity.class);
    context.startactivity(intent);
  }

  private string bytearraytohexstring(byte[] inarray) {
    int i, j, in;
    string[] hex = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a",
        "b", "c", "d", "e", "f" };
    string out = "";


    for (j = 0; j < inarray.length; ++j) {
      in = (int) inarray[j] & 0xff;
      i = (in >> 4) & 0x0f;
      out += hex[i];
      i = in & 0x0f;
      out += hex[i];
    }
    return out;
  }
}