首先封装一下volley 请求

public class CustomRequest extends StringRequest {

    private static final String TAG = CustomRequest.class.getSimpleName();
    private String mBody;
    private Map<String, String> mHeaders = new HashMap<>();

    public CustomRequest(int method, String url, Response.Listener<String> listener, Response.ErrorListener errorListener) {
        super(method, url, listener, errorListener);
　　　　　//设置消息头
        mHeaders.put("按需求写自己的内容", "按需求写自己的内容")；
　　　　　mHeaders.put("accetp"，"application/json");
　　　　　//可以有很多个

}

    @Override
    public Map<String, String> getHeaders() throws AuthFailureError {
        Log.i(TAG, mHeaders.toString());
        return mHeaders;
    }

    @Override
    public byte[] getBody() throws AuthFailureError {
        try {
            return TextUtils.isEmpty(mBody) ? super.getBody() : mBody.getBytes("utf-8");
        } catch (UnsupportedEncodingException e) {
//            Log.e(TAG, "getBody", e);
        }
        return super.getBody();
    }

    public void setBody(String body) {
        mBody = body;
    }

    public Map<String, String> getResonseHeaders() {
        return super.getResonseHeaders();
    }

}

其次我们还要封装一个请求类

public class CustomRequester<Resp extends Response> {
    private static final String TAG = "CustomRequester";
    private final Context mContext;
    private final Class<Resp> mClazz;
    private final com.android.volley.Response.ErrorListener mErrorListener = new com.android.volley.Response.ErrorListener() {
        @Override
        public void one rrorResponse(VolleyError volleyError) {
            int statusCode = volleyError == null ? 0 : volleyError.networkResponse == null ? 0 : volleyError.networkResponse.statusCode;
            Log.e(TAG, "statusCode: " + statusCode, volleyError);
            if (mTag == null) {
                return;
            }
            one rror();
            if (statusCode == 0) {
                onNetError();
            } else if (statusCode == 401) {//不同的请求码做不同的处理
            } else if (statusCode == 404) {
            } else if (statusCode == 400) {
            } else if (statusCode == 403) {
                
            } else {
                String json = volleyError.networkResponse.data =http://www.mamicode.com/= null ?"" : new String(volleyError.networkResponse.data);
                if (!TextUtils.isEmpty(json)) {
                    if (mContext instanceof Activity) {
                        Log.i(TAG, "json " + json);
                        try {
                            json = JSON.parseObject(json, Response.class).getMessage();
//                            one rror(json);
                        } catch (Exception e) {
                            one rror(json + "not json format!");
                        }
                    }
                }
            }
        }
    };

    private final com.android.volley.Response.Listener<String> mResponseListener = new com.android.volley.Response.Listener<String>() {
        @Override
        public void onResponse(String json) {
            Log.i(TAG, "json " + json);
            CustomRequester.this.onResponse(json);
            if (mTag == null) {
                return;
            }
            try {
                final Resp resp = JSON.parseObject(json, mClazz);
                if (resp != null) {
                    onSuccess(resp); //请求成功 这里直接返回解析好的 model
                }
            } catch (Exception e) {
                Log.e(TAG, "onResponse", e);
            }
        }
    };
    private String mTag;

    public void onResponse(String json) {
    }


    public void onSuccess(Resp resp) {
    }

    public void one rror() {
    }

    public void onNoFoundError() {
        if (mContext instanceof Activity) {
        }
    }

    public CustomRequester(Class<Resp> clazz) {
        mContext = null;
        mClazz = clazz;
    }

    public CustomRequester(Context context, Class<Resp> clazz) {
        mContext = context;
        mClazz = clazz;
    }

    public void cancelAll() {
        final String tag = mTag;
        mTag = null;
        if (!TextUtils.isEmpty(tag)) {
            MyApplication.getInstance().getRequestQueue().cancelAll(tag);
        }
    }

　　　　//Post 请求
    public CustomRequest post(String url, int page, String body) {
        final RequestQueue queue = MyApplication.getInstance().getRequestQueue();
        final CustomRequest request = new CustomRequest(Request.Method.POST, url, mResponseListener, mErrorListener);
        try {
            final Map<String, String> header = request.getHeaders();
            header.remove("Range");
            if (page > 0) {
                header.put("Range", String.format("page:%1$d,max:10", page));
            }
        } catch (AuthFailureError authFailureError) {
            authFailureError.printStackTrace();
        }
        mTag = "post," + url + "," + body;
        request.setTag(mTag);

        Log.i(TAG, mTag);
        request.setBody(body);
        queue.add(request);
        return request;
    }
　　　　//Get 请求
    public CustomRequest get(String url, int page, String body) {
        final RequestQueue queue = YZApplication.getInstance().getRequestQueue();
        final CustomRequest request = new CustomRequest(Request.Method.GET, url, mResponseListener, mErrorListener);
        try {
            final Map<String, String> header = request.getHeaders();
            header.remove("Range");
            if (page > 0) {
                header.put("Range", String.format("page:%1$d,max:10", page));
            }
        } catch (AuthFailureError authFailureError) {
            authFailureError.printStackTrace();
        }
        mTag = "post," + url + "," + body;
        request.setTag(mTag);

        Log.i(TAG, mTag);
        request.setBody(body);
        queue.add(request);
        return request;
    }
　
　　　　//Put 请求
    public CustomRequest put(String url, int page, String body) {
        final RequestQueue queue = MyApplication.getInstance().getRequestQueue();
        final CustomRequest request = new CustomRequest(Request.Method.PUT, url, mResponseListener, mErrorListener);

        try {
            final Map<String, String> header = request.getHeaders();
            header.remove("Range");
            if (page > 0) {
                header.put("Range", String.format("page:%1$d,max:10", page));
            }
        } catch (AuthFailureError authFailureError) {
            authFailureError.printStackTrace();
        }
        mTag = "put," + url + "," + body;
        request.setTag(mTag);
        request.setBody(body);
        queue.add(request);
        return request;
    }
　　　　//Delete 请求
    public CustomRequest delete(String url, int page, String body) {
        final RequestQueue queue = MyApplication.getInstance().getRequestQueue();
        final CustomRequest request = new CustomRequest(Request.Method.DELETE, url, mResponseListener, mErrorListener);
        try {
            final Map<String, String> header = request.getHeaders();
            header.remove("Range");
            if (page > 0) {
                header.put("Range", String.format("page:%1$d,max:10", page));
            }
        } catch (AuthFailureError authFailureError) {
            authFailureError.printStackTrace();
        }
        mTag = "delete," + url + "," + body;
        request.setTag(mTag);
        request.setBody(body);
        queue.add(request);
        return request;
    }

}

调用
Response是你的model
1.

private AppRequester<Response> mRequester;

2.
mRequester = new AppRequester<Response>(this, Response.class) {

    @Override
    public void onSuccess(Response response) {
        super.onSuccess(response);
　　　　　　//成功的操作，展示页面等
    }

　　@Override
　　public void one rror() {
  　　  super.onError();
　　}

};

3.

//get方式
mRequester.get("URL");

//post 方式  
mRequester.post(URL, JSON.toJSONString(model));

这样就好了，使用时特别方便，你们试试。

Android 网络请求库volley的封装，让请求更方便