* Volley是Android平台的网络通信库：更快，更简单，更健壮
* Volley提供的功能：
* 1：JSON，图片（异步）
* 2.网络请求排序
* 3.网络请求的优先级处理
* 4.缓存
* 5.多级别的取消请求
* 6.与Activity生命周期联动
适合：频繁的，数据量比较小的请求
//Volley实现JSON字符串请求
1 //Volley实现JSON字符串请求
2 //最小sdk8.0以上
3 public class MainActivity extends Activity {
4
5 @Override
6 protected void onCreate(Bundle savedInstanceState) {
7 super.onCreate(savedInstanceState);
8 setContentView(R.layout.fragment_main);
9 getJSONVolley();
10
11 }
12
13 // 获取json字符串
14 public void getJSONVolley() {
15
16 RequestQueue requestQueue = Volley.newRequestQueue(this);
17
18 String JSONDateUrl = "http://www.imooc.com/api/teacher?type=4&num=30";
19 JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(
20 Request.Method.GET, JSONDateUrl, null,
21 new Response.Listener<JSONObject>() {
22 public void onResponse(JSONObject response) {
23
24 System.out.println("--->>response:" + response);
25 }
26 }, new Response.ErrorListener() {
27 public void onErrorResponse(
28 com.android.volley.VolleyError error) {
29
30 System.out.println("--->>error");
31 }
32 });
33
34 requestQueue.add(jsonObjectRequest);
35 }
36 }
1 ////使用Volley从服务器下载图片
2 //最小sdk8.0以上
3 public class MainActivity extends Activity {
4 ImageView imageView;
5
6 @Override
7 protected void onCreate(Bundle savedInstanceState) {
8 super.onCreate(savedInstanceState);
9 setContentView(R.layout.fragment_main);
10 imageView = (ImageView) findViewById(R.id.imageView1);
11 loadImageVolley();
12
13 }
14
15 // 使用Volley从服务器下载图片
16 // http://localhost:8080/web/Sky.jpg
17 public void loadImageVolley() {
18 String imageurl = "http://172.16.166.195:8080/web/Sky.jpg";
19 RequestQueue requestQueue = Volley.newRequestQueue(this);
20 final LruCache<String, Bitmap> lruCache = new LruCache<String, Bitmap>(
21 20);
22 ImageCache imageCache = new ImageCache() {
23
24 @Override
25 public void putBitmap(String url, Bitmap bitmap) {
26 // TODO Auto-generated method stub
27 lruCache.put(url, bitmap);
28 }
29
30 @Override
31 public Bitmap getBitmap(String url) {
32 // TODO Auto-generated method stub
33 return lruCache.get(url);
34 }
35 };
36 ImageLoader imageLoader = new ImageLoader(requestQueue, imageCache);
37 ImageListener listener = imageLoader.getImageListener(imageView,
38 R.drawable.ic_launcher, R.drawable.ic_launcher);
39 imageLoader.get(imageurl, listener);
40
41 }
42 }
1 //使用 NetWorkImageView 完成图片加载
2 //最小sdk8.0以上
3 public class MainActivity extends Activity {
4 NetworkImageView imageView;
5
6 @Override
7 protected void onCreate(Bundle savedInstanceState) {
8 super.onCreate(savedInstanceState);
9 setContentView(R.layout.fragment_main);
10 imageView = (NetworkImageView) findViewById(R.id.imageView1);
11 NetWorkImageViewVolley();
12
13 }
14
15 public void NetWorkImageViewVolley() {
16 String imageurl = "http://172.16.166.195:8080/web/Sky.jpg";
17 RequestQueue requestQueue = Volley.newRequestQueue(this);
18 final LruCache<String, Bitmap> lruCache = new LruCache<String, Bitmap>(
19 20);
20 ImageCache imageCache = new ImageCache() {
21
22 @Override
23 public void putBitmap(String url, Bitmap bitmap) {
24 // TODO Auto-generated method stub
25 lruCache.put(url, bitmap);
26 }
27
28 @Override
29 public Bitmap getBitmap(String url) {
30 // TODO Auto-generated method stub
31 return lruCache.get(url);
32 }
33
34 };
35 ImageLoader imageLoader = new ImageLoader(requestQueue, imageCache);
36
37 imageView.setTag("url");
38 imageView.setImageUrl(imageurl, imageLoader);
39
40 }
41 }
