【Android进阶】-Android 网络通信框架 Volley

引言

在Volley出来之前，我们在程序中需要和服务器通信时，使用的通常是HttpURLConnection，HttpClient或者在这两者基础上封装的框架。Volley是谷歌发布的Android平台上的网络通信框架，它能够使Android平台上的网络通信更快，更简单，更健壮。

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Volley提供的功能

• JSON，图像等的异步下载；
• 网络请求的排序；
• 网络请求的优先级处理
• 缓存
• 多级别取消请求
• 和Activity生命周期联动

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在项目中使用Volley

大家可以去git上下载Volley的源码，然后编译成jar包加入到项目中，也可以下载编译好的jar包，下载地址：http://download.youkuaiyun.com/detail/tailyou/9077899

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Volley-GET请求

private void volleyGet() {
        RequestQueue requestQueue = Volley.newRequestQueue(this);
        String url = "http://iscs.hebut.edu.cn/SingleLoginService/ajax/LoadUserDetailAction.action?userName=201322102032";
        StringRequest stringRequest = new StringRequest(Request.Method.POST, url, new Response.Listener<String>() {
            @Override
            public void onResponse(String response) {
                Toast.makeText(getApplicationContext(), response, Toast.LENGTH_LONG).show();
            }
        }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError volleyError) {

            }
        });
        requestQueue.add(stringRequest);
    }

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Volley-POST请求

private void volleyPost() {
        RequestQueue requestQueue = Volley.newRequestQueue(this);
        String url = "http://iscs.hebut.edu.cn/SingleLoginService/ajax/LoadUserDetailAction.action";
        StringRequest stringRequest = new StringRequest(Request.Method.POST, url, new Response.Listener<String>() {
            @Override
            public void onResponse(String response) {
                Toast.makeText(getApplicationContext(), response, Toast.LENGTH_LONG).show();
            }
        }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError volleyError) {

            }
        }) {
            @Override
            protected Map<String, String> getParams() throws AuthFailureError {
                Map<String, String> params = new HashMap<String, String>();
                params.put("userName", "201322102032");
                return params;
            }
        };
        requestQueue.add(stringRequest);
    }

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Volley-加载JSON

private void getJSONByVolley() {
        RequestQueue requestQueue = Volley.newRequestQueue(this);
        String url = "http://iscs.hebut.edu.cn/SingleLoginService/ajax/LoadUserDetailAction.action?userName=201322102032";
        JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(Request.Method.GET, url, null, new Response.Listener<JSONObject>() {
            @Override
            public void onResponse(JSONObject jsonObject) {
                Toast.makeText(getApplicationContext(), jsonObject.toString(), Toast.LENGTH_LONG).show();
            }
        }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError volleyError) {

            }
        });
        requestQueue.add(jsonObjectRequest);
    }

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Volley-加载图片

private void getImageByVolley() {
        ImageView imageView = (ImageView) findViewById(R.id.img);
        String imgUrl = "http://202.113.127.138:8083/EyesCare/images/143160583556420150101_121418.jpg";
        RequestQueue requestQueue = Volley.newRequestQueue(this);
        final LruCache<String, Bitmap> lruCache = new LruCache<>(20);
        ImageLoader.ImageCache imageCache = new ImageLoader.ImageCache() {
            @Override
            public Bitmap getBitmap(String s) {
                return lruCache.get(s);
            }

            @Override
            public void putBitmap(String s, Bitmap bitmap) {
                lruCache.put(s, bitmap);
            }
        };
        ImageLoader imageLoader = new ImageLoader(requestQueue, imageCache);
        ImageLoader.ImageListener listener = ImageLoader.getImageListener(imageView, R.drawable.abc_ic_ab_back_mtrl_am_alpha, R.drawable.abc_ab_share_pack_mtrl_alpha);
        imageLoader.get(imgUrl, listener);
    }

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Volley-NetworkImageView显示图片

private void showImageByNetworkImageView() {
        NetworkImageView nImageView = (NetworkImageView) findViewById(R.id.nImg);
        String imgUrl = "http://202.113.127.138:8083/EyesCare/images/143160583556420150101_121418.jpg";
        RequestQueue requestQueue = Volley.newRequestQueue(this);
        final LruCache<String, Bitmap> lruCache = new LruCache<>(20);
        ImageLoader.ImageCache imageCache = new ImageLoader.ImageCache() {
            @Override
            public Bitmap getBitmap(String s) {
                return lruCache.get(s);
            }

            @Override
            public void putBitmap(String s, Bitmap bitmap) {
                lruCache.put(s, bitmap);
            }
        };
        ImageLoader imageLoader = new ImageLoader(requestQueue, imageCache);
        nImageView.setImageUrl(imgUrl, imageLoader);
    }