Android應用開發之獲取web服務器xml數據

實驗步驟：

1、 配置J2EE開發環境，並部署web應用viderweb，啟動服務

2、 打開浏覽器訪問網址

http://localhost:8080/videoweb/video/list.do

演示xml數據

3、 創建Android客戶端工程，實現訪問上面的網址並且將取得的xml數據進行解析並顯示，如下圖：

Android客戶端代碼

程序流程

資源

1. <resources>
2. <string name="app_name">視頻資訊客戶端</string>
3. <string name="error">網絡連接失敗</string>
4. </resources>

布局

main.xml

1. <?xml version="1.0" encoding="utf-8"?>
2. <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
3. android:layout_width="fill_parent"
4. android:layout_height="fill_parent"
5. android:orientation="vertical" >
7. <ListView
8. android:id="@+id/listView"
9. android:layout_width="fill_parent"
10. android:layout_height="fill_parent" />
12. </LinearLayout>

item.xml

1. <?xml version="1.0" encoding="utf-8"?>
2. <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
3. android:layout_width="fill_parent"
4. android:layout_height="wrap_content"
5. android:orientation="horizontal" >
7. <TextView
8. android:id="@+id/title"
9. android:layout_width="250dip"
10. android:layout_height="wrap_content" />
12. <TextView
13. android:id="@+id/timelength"
14. android:layout_width="fill_parent"
15. android:layout_height="wrap_content" />
17. </LinearLayout>

添加業務bean類Video

1. package cn.class3g.domain;
3. public class Video {
4. private Integer id;
5. private String title;
6. private Integer timelength;
8. public Video(Integer id, String title, Integer timelength) {
9. super();
10. this.id = id;
11. this.title = title;
12. this.timelength = timelength;
13. }
14. public Video() { }
15. public Integer getId() {
16. return id;
17. }
18. public void setId(Integer id) {
19. this.id = id;
20. }
21. public String getTitle() {
22. return title;
23. }
24. public void setTitle(String title) {
25. this.title = title;
26. }
27. public Integer getTimelength() {
28. return timelength;
29. }
30. public void setTimelength(Integer timelength) {
31. this.timelength = timelength;
32. }
33. public String toString() {
34. return "Video [id=" + id + ", title=" + title + ", timelength="
35. + timelength + "]";
36. }
37. }

添加業務類VideoService類

1. package cn.class3g.service;
2. ...
3. public class VideoService {
5. /**
6. * 從服務器獲取最新的視頻資訊
7. *
8. * @return
9. * @throws Throwable
10. */
11. public static List<Video> getLastVideos() throws Throwable {
12. String path =
13. "http://192.168.1.102:8080/videoweb/video/list.do";//
14. 實驗環境中使用pc的ip，不能用localhost或127.0.0.1
15. URL url = new URL(path);
16. HttpURLConnection conn = (HttpURLConnection) url.openConnection();
17. conn.setConnectTimeout(5 * 1000);
18. conn.setRequestMethod("GET");
19. InputStream inStream = conn.getInputStream();
20. return parseXML(inStream);
21. }
23. private static List<Video> parseXML(InputStream inStream) throws Exception {
24. Video video = null;
25. List<Video> videos = null;
26. XmlPullParser pullParser = Xml.newPullParser();
27. pullParser.setInput(inStream, "UTF-8");
29. int event = pullParser.getEventType();// 觸發第一個事件
31. while (event != XmlPullParser.END_DOCUMENT) {
32. switch (event) {
33. case XmlPullParser.START_DOCUMENT:
34. videos = new ArrayList<Video>();
35. break;
36. case XmlPullParser.START_TAG:
37. if ("video".equals(pullParser.getName())) {
38. int id = new Integer(pullParser.getAttributeValue(0));
39. video = new Video();
40. video.setId(id);
41. }
42. if (video != null) {
43. if ("title".equals(pullParser.getName())) {
44. video.setTitle(pullParser.nextText());
45. }
46. if ("timelength".equals(pullParser.getName())) {
47. video.setTimelength(new Integer(pullParser.nextText()));
48. }
49. }
50. break;
52. case XmlPullParser.END_TAG:
53. if ("video".equals(pullParser.getName())) {
54. videos.add(video);
55. video = null;
56. }
57. break;
58. }
59. event = pullParser.next();
60. }
61. return videos;
62. }
63. }

Activity類MyVideoNewsActivity

1. public class MyVideoNewsActivity extends Activity {
3. public void onCreate(Bundle savedInstanceState) {
4. super.onCreate(savedInstanceState);
5. setContentView(R.layout.main);
7. try {
8. List<Video> videos = VideoService.getLastVideos();//獲取最新視頻資訊
9. ListView listView = (ListView)this.findViewById(R.id.listView);
10. List<HashMap<String, Object>> data = new ArrayList<HashMap<String,Object>>();
11. for(Video video : videos){
12. HashMap<String, Object> item = new HashMap<String, Object>();
13. item.put("title", video.getTitle());
14. item.put("timelength", "時長:"+video.getTimelength());
15. item.put("id", video.getId());
16. data.add(item);
17. }
18. SimpleAdapter adapter = new SimpleAdapter(this, data, R.layout.item,
19. new String[]{"title","timelength"}, new int[]{R.id.title, R.id.timelength});
20. listView.setAdapter(adapter);
21. } catch (Throwable e) {
22. Log.e("TAG", e.toString());
23. Toast.makeText(this, R.string.error, 1).show();
24. }
25. }
26. }

Androd中獲取網頁代碼

布局

1. <Button
2. android:layout_width="fill_parent"
3. android:layout_height="wrap_content"
4. android:text="@string/btn_text"
5. android:id="@+id/showBtn"
6. />
8. <ImageView
9. android:layout_width="wrap_content"
10. android:layout_height="wrap_content"
11. android:id="@+id/imageView"
12. />

代碼：在前面的ImageService.getImage（）方法基礎上修改即可

HtmlService

1. public class HtmlService {
2. /**
3. * 獲取給定路徑的html代碼
4. * @param path 網頁路徑
5. * @return
6. * @throws Exception
7. */
8. public static String getHtml(String path) throws Exception{
9. URL url = new URL(path);
10. //get //post
11. HttpURLConnection conn = (HttpURLConnection)url.openConnection();
12. conn.setRequestMethod("GET");
13. conn.setConnectTimeout(5*1000);
14. InputStream inStream = conn.getInputStream();
16. ByteArrayOutputStream outStream = new ByteArrayOutputStream();
17. byte[] buffer = new byte[1024];
18. int len = 0;
19. while( (len = inStream.read(buffer)) !=-1 ){
20. outStream.write(buffer, 0, len);
21. }
22. byte[] data = outStream.toByteArray();//網頁的二進制數據
23. outStream.close();
24. inStream.close();
25. return new String(data, "gb2312");
26. }
27. }

ShowHtmlActivity

1. public void onClick(View v) {
2. String path = pathText.getText().toString();
3. try {
4. String htmlcode = HtmlService.getHtml(path);
5. resultView.setText(htmlcode);
6. } catch (Exception e) {
7. Log.e(TAG, e.toString());
8. Toast.makeText(ShowHtmlActivity.this, R.string.error, 1).show();
9. }
10. }