NFC技术：让Android自动运行程序

//实现向NFC标签写入包，然后将NFC靠近手机背面摄像头位置，自动运行写入的程序
public class RunAppActivity extends Activity {
    private Button button;
    private String mpackage;
    private NfcAdapter nfcAdapter;
    private PendingIntent mPendingIntent;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);

        setContentView(R.layout.fragment_main);
        button = (Button) findViewById(R.id.button1);
        nfcAdapter = NfcAdapter.getDefaultAdapter(this);
        mPendingIntent = PendingIntent.getActivity(this, 0, new Intent(this,
                getClass()), 0);

    }

    @Override
    protected void onNewIntent(Intent intent) {
        // TODO Auto-generated method stub
        // 当清单文件中设置为"singleTop"时，oncreate（）只调用一次，而onNewIntent（）每次调用
        super.onNewIntent(intent);
        if (mpackage == null)
            return;
        // 第一步获得Tag
        Tag detectetTag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);
        // 第二步写入标签
        writeNFCTag(detectetTag);
    }

    private void writeNFCTag(Tag tag) {
        // TODO Auto-generated method stub
        if (tag == null) {
            return;
        }

        NdefMessage ndefMessage = new NdefMessage(
                new NdefRecord[] { NdefRecord.createApplicationRecord(mpackage) });

        int size = ndefMessage.toByteArray().length;
        try {
            Ndef ndef = Ndef.get(tag);
            if (ndef != null) {
                ndef.connect();
                // 是否支持可写
                if (!ndef.isWritable()) {
                    return;
                }
                // 判断是否可以容纳要写入的数据
                if (ndef.getMaxSize() < size) {
                    return;
                }
                ndef.writeNdefMessage(ndefMessage);
                Toast.makeText(this, "NFC成功写入", 0).show();
            }
        } catch (Exception e) {
            // TODO: handle exception
        }
    }

    @Override
    protected void onResume() {
        // TODO Auto-generated method stub
        super.onResume();
        // 获得焦点， 设置这个窗口优先级高于所有可以处理NFC的窗口
        if (nfcAdapter != null) {
            nfcAdapter.enableForegroundDispatch(this, mPendingIntent, null,
                    null);
        }
    }

    @Override
    protected void onPause() {
        // TODO Auto-generated method stub
        super.onPause();
        // 程序退出，窗口恢复默认
        if (nfcAdapter != null) {
            nfcAdapter.disableForegroundDispatch(this);
        }
    }

    public void onclick(View view) {
        Intent intent = new Intent(this, InstallAppListActivity.class);
        startActivityForResult(intent, 0);
    }
}

//显示所有安装的包
public class InstallAppListActivity extends ListActivity implements
        OnItemClickListener {
    private List<String> mpackages = new ArrayList<String>();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        PackageManager manager = getPackageManager();
        List<PackageInfo> packageInfos = manager
                .getInstalledPackages(PackageManager.GET_ACTIVITIES);

        for (PackageInfo packageInfo : packageInfos) {
            mpackages.add(packageInfo.applicationInfo.loadLabel(manager) + "
"
                    + packageInfo.packageName);

        }
        ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
                android.R.layout.simple_list_item_1, android.R.id.text1,
                mpackages);
        setListAdapter(adapter);
        getListView().setOnItemClickListener(this);
    }

    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position,
            long id) {
        Intent intent = new Intent();
        intent.putExtra("Packagename", mpackages.get(position));
        setResult(1, intent);
        finish();
    }

}