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12、NFC技术：读写NFC标签中的Uri数据

功能实现，如下代码所示：

读写NFC标签的Uri 主Activity

  1 import cn.read.write.uri.library.UriRecord;
  2 import android.app.Activity;
  3 import android.content.Intent;
  4 import android.nfc.NdefMessage;
  5 import android.nfc.NdefRecord;
  6 import android.nfc.NfcAdapter;
  7 import android.nfc.Tag;
  8 import android.nfc.tech.Ndef;
  9 import android.os.Bundle;
 10 import android.view.View;
 11 import android.widget.TextView;
 12 import android.widget.Toast;
 13 
 14 /**
 15  * 读写NFC标签的Uri
 16  * @author dr
 17  *
 18  */
 19 public class ReadWriteUriMainActivity extends Activity {
 20     private TextView mSelectUri;
 21     private String mUri;
 22 
 23     @Override
 24     public void onCreate(Bundle savedInstanceState) {
 25         super.onCreate(savedInstanceState);
 26         setContentView(R.layout.activity_read_write_uri_main);
 27         mSelectUri = (TextView) findViewById(R.id.textview_uri);
 28     }
 29 
 30     public void onClick_SelectUri(View view) {
 31         Intent intent = new Intent(this, UriListActivity.class);
 32         startActivityForResult(intent, 1);
 33     }
 34 
 35     @Override
 36     protected void onActivityResult(int requestCode, int resultCode, Intent data) {
 37         if (requestCode == 1 && resultCode == 1) {
 38             mUri = data.getStringExtra("uri");
 39             mSelectUri.setText(mUri);
 40         }
 41     }
 42 
 43     public void onNewIntent(Intent intent) {
 44         if (mUri == null) {
 45             Intent myIntent = new Intent(this, ShowNFCTagContentActivity.class);
 46             myIntent.putExtras(intent);
 47             myIntent.setAction(NfcAdapter.ACTION_NDEF_DISCOVERED);
 48             startActivity(myIntent);
 49         } else {  // write nfc
 50             Tag tag = intent.getParcelableExtra(NfcAdapter.EXTRA_TAG);
 51             NdefMessage ndefMessage = new NdefMessage(
 52                     new NdefRecord[] { createUriRecord(mUri) });
 53             if (writeTag(ndefMessage, tag)) {
 54                 mUri = null;
 55                 mSelectUri.setText("");
 56             }
 57         }
 58     }
 59 
 60     public NdefRecord createUriRecord(String uriStr) {
 61         byte prefix = 0;
 62         for (Byte b : UriRecord.URI_PREFIX_MAP.keySet()) {
 63             String prefixStr = UriRecord.URI_PREFIX_MAP.get(b).toLowerCase();
 64             if ("".equals(prefixStr))
 65                 continue;
 66             if (uriStr.toLowerCase().startsWith(prefixStr)) {
 67                 prefix = b;
 68                 uriStr = uriStr.substring(prefixStr.length());
 69                 break;
 70             }
 71         }
 72         byte[] data = new byte[1 + uriStr.length()];
 73         data[0] = prefix;
 74         System.arraycopy(uriStr.getBytes(), 0, data, 1, uriStr.length());
 75 
 76         NdefRecord record = new NdefRecord(NdefRecord.TNF_WELL_KNOWN,
 77                 NdefRecord.RTD_URI, new byte[0], data);
 78         return record;
 79     }
 80 
 81     boolean writeTag(NdefMessage message, Tag tag) {
 82         int size = message.toByteArray().length;
 83         try {
 84             Ndef ndef = Ndef.get(tag);
 85             if (ndef != null) {
 86                 ndef.connect();
 87                 if (!ndef.isWritable()) {
 88                     return false;
 89                 }
 90                 if (ndef.getMaxSize() < size) {
 91                     return false;
 92                 }
 93                 ndef.writeNdefMessage(message);
 94                 Toast.makeText(this, "ok", Toast.LENGTH_LONG).show();
 95                 return true;
 96             }
 97         } catch (Exception e) {
 98             // TODO: handle exception
 99         }
100         return false;
101     }
102 }

读写NFC标签的Uri 主xml

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3     android:layout_width="match_parent"
 4     android:layout_height="match_parent"
 5     android:orientation="vertical" >
 6 
 7     <Button
 8         android:layout_width="match_parent"
 9         android:layout_height="wrap_content"
10         android:onClick="onClick_SelectUri"
11         android:text="选择Uri" />
12 
13     <TextView
14         android:id="@+id/textview_uri"
15         android:layout_width="match_parent"
16         android:layout_height="wrap_content"
17         android:textSize="16sp" />
18 
19     <TextView
20         android:layout_width="match_parent"
21         android:layout_height="wrap_content"
22         android:layout_marginTop="30dp"
23         android:text="请将NFC标签靠近手机背面读取或写入Uri"
24         android:textColor="#F00"
25         android:textSize="16sp" />
26 
27     <ImageView
28         android:layout_width="match_parent"
29         android:layout_height="match_parent"
30         android:src="@drawable/read_nfc_tag" />
31 
32 </LinearLayout>

显示URI列表Activity

 1 import android.app.ListActivity;
 2 import android.content.Intent;
 3 import android.os.Bundle;
 4 import android.view.View;
 5 import android.widget.AdapterView;
 6 import android.widget.AdapterView.OnItemClickListener;
 7 import android.widget.ArrayAdapter;
 8 
 9 /**
10  * 显示URI列表
11  * @author dr
12  *
13  */
14 public class UriListActivity extends ListActivity implements
15         OnItemClickListener {
16     private String uris[] = new String[] { "http://www.google.com",
17             "http://www.apple.com", "http://developer.apple.com",
18             "http://www.126.com", "ftp://192.168.17.160",
19             "https://192.168.17.120", "smb://192.168.17.100" };
20 
21     @Override
22     public void onCreate(Bundle savedInstanceState) {
23         super.onCreate(savedInstanceState);
24         ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(this,
25                 android.R.layout.simple_list_item_1, android.R.id.text1, uris);
26         setListAdapter(arrayAdapter);
27         getListView().setOnItemClickListener(this);
28     }
29 
30     @Override
31     public void onItemClick(AdapterView<?> parent, View view, int position,
32             long id) {
33         Intent intent = new Intent();
34         intent.putExtra("uri", uris[position]);
35         setResult(1, intent);
36         finish();
37     }
38 
39 }

显示NFC标签内容Activity

 1 import android.app.Activity;
 2 import android.nfc.NdefMessage;
 3 import android.nfc.NdefRecord;
 4 import android.nfc.NfcAdapter;
 5 import android.nfc.Tag;
 6 import android.nfc.tech.Ndef;
 7 import android.os.Bundle;
 8 import android.os.Parcelable;
 9 import android.widget.TextView;
10 import cn.read.write.uri.library.UriRecord;
11 
12 /**
13  * 显示NFC标签内容
14  * @author dr
15  *
16  */
17 public class ShowNFCTagContentActivity extends Activity {
18     private TextView mTagContent;
19     private Tag mDetectedTag;
20     private String mTagText;
21 
22     @Override
23     public void onCreate(Bundle savedInstanceState) {
24         super.onCreate(savedInstanceState);
25         setContentView(R.layout.activity_show_nfctag_content);
26         mTagContent = (TextView) findViewById(R.id.textview_tag_content);
27         mDetectedTag = getIntent().getParcelableExtra(NfcAdapter.EXTRA_TAG);
28         Ndef ndef = Ndef.get(mDetectedTag);
29         mTagText = ndef.getType() + "
 max size:" + ndef.getMaxSize()
30                 + " bytes

";
31 
32         readNFCTag();
33 
34         mTagContent.setText(mTagText);
35     }
36 
37     private void readNFCTag() {
38         if (NfcAdapter.ACTION_NDEF_DISCOVERED.equals(getIntent().getAction())) {
39             Parcelable[] rawMsgs = getIntent().getParcelableArrayExtra(
40                     NfcAdapter.EXTRA_NDEF_MESSAGES);
41 
42             NdefMessage ndefMessage = null;
43 
44             int contentSize = 0;
45             if (rawMsgs != null) {
46                 if (rawMsgs.length > 0) {
47                     ndefMessage = (NdefMessage) rawMsgs[0];
48                     contentSize = ndefMessage.toByteArray().length;
49                 } else {
50                     return;
51                 }
52             }
53             try {
54                 NdefRecord ndefRecord = ndefMessage.getRecords()[0];
55                 UriRecord uriRecord = UriRecord.parse(ndefRecord);
56                 mTagText += uriRecord.getUri().toString() + "

Uri
"
57                         + contentSize + " bytes";
58             } catch (Exception e) {
59                 // TODO: handle exception
60             }
61         }
62     }
63 
64 }

显示NFC标签内容xml

 1 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 2     android:layout_width="match_parent"
 3     android:layout_height="match_parent"
 4     android:orientation="vertical" >
 5 
 6     <TextView
 7         android:id="@+id/textview_tag_content"
 8         android:layout_width="match_parent"
 9         android:layout_height="wrap_content"
10         android:layout_margin="6dp"
11         android:textSize="16sp" />
12 
13 </LinearLayout>

AndroidManifest.xml

 1 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
 2     package="cn.eoe.read.write.uri"
 3     android:versionCode="1"
 4     android:versionName="1.0" >
 5 
 6     <uses-sdk
 7         android:minSdkVersion="15"
 8         android:targetSdkVersion="15" />
 9 
10     <uses-permission android:name="android.permission.NFC" />
11 
12     <application
13         android:icon="@drawable/ic_launcher"
14         android:label="@string/app_name"
15         android:theme="@style/AppTheme" >
16         <activity
17             android:name=".ReadWriteUriMainActivity"
18             android:label="读写NFC标签的Uri"
19             android:launchMode="singleTask" >
20             <intent-filter>
21                 <action android:name="android.intent.action.MAIN" />
22 
23                 <category android:name="android.intent.category.LAUNCHER" />
24             </intent-filter>
25             <intent-filter>
26                 <action android:name="android.nfc.action.NDEF_DISCOVERED" />
27 
28                 <category android:name="android.intent.category.DEFAULT" />
29 
30                 <data android:scheme="http" />
31                 <data android:scheme="https" />
32                 <data android:scheme="ftp" />
33             </intent-filter>
34             <intent-filter>
35                 <action android:name="android.nfc.action.NDEF_DISCOVERED" />
36 
37                 <category android:name="android.intent.category.DEFAULT" />
38                 <data android:mimeType="text/plain" />
39             </intent-filter>
40         </activity>
41         <activity
42             android:name="cn.eoe.read.write.uri.ShowNFCTagContentActivity"
43             android:label="显示NFC标签内容" />
44         <activity
45             android:name="cn.eoe.read.write.uri.UriListActivity"
46             android:label="选择Uri" />
47     </application>
48 
49 </manifest>

DEMO下载地址：http://download.csdn.net/detail/androidsj/7680247

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原文地址：https://www.cnblogs.com/androidsj/p/3856435.html