Android應用開發之獲取網絡數據

J2SE實現網絡圖片的獲取

1. public static void main(String[] args) throws Exception {
2. String path = "http://img.linuxidc.com/img/Android.png";
4. URL url = new URL(path);
6. HttpURLConnection conn = (HttpURLConnection) url.openConnection();
7. conn.setRequestMethod("GET");
8. conn.setConnectTimeout(5*1000);
9. InputStream inStream = conn.getInputStream();
11. ByteArrayOutputStream outStream = new ByteArrayOutputStream();
12. byte[] buffer = new byte[1024];
14. int len=0;
15. while((len=inStream.read(buffer))!=-1){
16. outStream.write(buffer,0,len);
17. }
19. byte[] data = outStream.toByteArray();
21. File f = new File("pic.jpg");
22. FileOutputStream fos = new FileOutputStream(f);
23. fos.write(data);
24. fos.close();
25. }

Androd中獲取網絡圖片

資源

1. <string name="btn_text">顯示網絡圖片</string>
2. <string name="error">下載圖片失敗！！</string>

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. />

添加ImageService類

1. package cn.class3g.service;
2. …
3. public class ImageService {
4. public static byte[] getImage(String path) throws Exception{
5. URL url = new URL(path);
6. //get //post
7. HttpURLConnection conn = (HttpURLConnection)url.openConnection();
8. conn.setRequestMethod("GET");
9. conn.setConnectTimeout(5*1000);
10. InputStream inStream = conn.getInputStream();
12. ByteArrayOutputStream outStream = new ByteArrayOutputStream();
13. byte[] buffer = new byte[1024];
14. int len = 0;
15. while( (len = inStream.read(buffer)) !=-1 ){
16. outStream.write(buffer, 0, len);
17. }
18. byte[] data = outStream.toByteArray();//圖片的二進制數據
19. outStream.close();
20. inStream.close();
21. return data;
22. }
23. }

Activity

1. public void onClick(View v) {
2. String path = "http://img.linuxidc.com/img/Android.png";
4. try {
5. byte[] data = ImageService.getImage(path);
7. Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);
8. imgView.setImageBitmap(bitmap);
10. } catch (Exception e) {
11. // e.printStackTrace();
12. Log.e("TAG", e.toString());
13. Toast.makeText(this, R.string.error, 1).show();
14. }
15. }

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. }