Volley自定义一个Request

之前通过源码简单的了解一下Volley.
1.Volley源码学习笔记_RequestQueue和BasicNetWork
2.Volley源码学习笔记_ExecutorDelivery
3.Volley源码学习笔记_CacheDispatcher和NetworkDispatcher
4.Volley源码学习笔记_Request

现在我们可以尝试自定义一个Volley请求。可以适用一般的get，post(请求类型是String)以及图片上传。
用到的jar：volley.jar, httpmime-4.1.1.jar

继承Request,并实现他的2个方法，之前的源码解析中我们也看了这2个方法是干什么的。

public class MyVolleyRequest extends Request<String> {    //构造函数    public MyVolleyRequest(int method, String url, Response.ErrorListener listener) {        super(method, url, listener);    }//对返回的数据进行解析    @Override    protected Response<String> parseNetworkResponse(NetworkResponse networkResponse) {        return null;    }//返回请求成功的数据    @Override    protected void deliverResponse(String s) {    }}

定义一些参数

 private MultipartEntity entity ;//一些带有关文件参数和读取的类    private Map<String, String> header;//请求头信息    private Response.Listener<String> mListener;//请求成功的监听    private Response.ErrorListener mErrorListener;//请求错误的监听    private String bodyContentType;//文件类型    private Map<String, String> params;    private List<File> files;    private String fileName;//文件组相关的参数名称    private  int kVolleyTimeOutMS=20*1000;//超时时间    private int kVolleyMaxRetryNum =2;//超时重试时间    private Priority mPriority = Request.Priority.NORMAL;//设置优先级

可以通过构造函数来设置响应的值，也可以设置set方法

  public MyVolleyRequest(int method, String url, Response.ErrorListener listener) {        super(method, url, listener);    }//get请求    public MyVolleyRequest(String url, VolleyResponseListener listener,Request.Priority priority,String tag) {        this(Method.GET, url, listener.getmErrorListener());        this.listener = listener;        mListener = listener.getmListener();        mErrorListener = listener.getmErrorListener();        if(priority!=null){            this.mPriority =priority;        }    }    //post请求    public MyVolleyRequest(String url, Map<String, String> header,Map<String, String> params, VolleyResponseListener listener,Request.Priority priority,String tag) {        this(Method.POST, url, listener.getmErrorListener());        this.listener = listener;        this.header = header;        mListener = listener.getmListener();        mErrorListener = listener.getmErrorListener();        this.params = params;        if(priority!=null){            this.mPriority =priority;        }        setTagAndRetryPolicy(tag,kVolleyTimeOutMS,kVolleyMaxRetryNum);    }    //上传图片  public MyVolleyRequest(String url, Map<String, String> header, VolleyResponseListener listener, Map<String, String> params, List<File> files, String fileName,Request.Priority priority,String tag) {        super(Method.POST, url, listener.getmErrorListener());        this.listener = listener;        this.header = header;        mListener = listener.getmListener();        mErrorListener = listener.getmErrorListener();        this.params = params;        this.files = files;        this.fileName = fileName;        entity=  new MultipartEntity();        bodyContentType =entity.getContentType().getValue();        buildMultipartEntity();        if(priority!=null){            this.mPriority =priority;        }    }

  // 编辑上传文件和参数的加到entity中    private void buildMultipartEntity() {        try {            if (files != null && files.size() > 0) {                for (File f : files) {                    //这里要是直接new FileBody(f),默认的content-type是application/octet-stream                    FileBody fileBody = new FileBody(f,"image/jpeg");                    entity.addPart(fileName, fileBody);                }                long fileLength = entity.getContentLength();                Log.i("Volley_qy", "上传文件的数目是：" + files.size() + ",上传文件的长度是: " + fileLength + " byte");            }            if (params != null && params.size() > 0) {                for (Map.Entry<String, String> entry : params.entrySet()) {                    Log.i("Volley_qy", "上传文件的参数是：(" + entry.getKey() + ":" + entry.getValue() + ")");                    entity.addPart(entry.getKey(), new StringBody(entry.getValue()));                }            }        } catch (UnsupportedEncodingException e) {            VolleyLog.e("UnsupportedEncodingException");        }    }

之后看看其他的方法
1.parseNetworkResponse

 //这里就直接按照StringJson中的解析方式来了    @Override    protected Response<String> parseNetworkResponse(NetworkResponse networkResponse) {        String parsed;        try {            parsed = new String(networkResponse.data, HttpHeaderParser.parseCharset(networkResponse.headers));        } catch (UnsupportedEncodingException var4) {            parsed = new String(networkResponse.data);        }        return Response.success(parsed, HttpHeaderParser.parseCacheHeaders(networkResponse));    }

2.deliverResponse

//请求接口成功 protected void deliverResponse(String s) {        Log.i("Volley_qy","请求成功返回的数据是："+s);   mListener.onResponse(s);    }

3.getParams和geBody

 //post请求，getparams一般不会调用,如果Request直接接触JsonRequest就会直接走getbody。但是你看源码就会发现，getbody中也会调用getParams()    @Override    public Map<String, String> getParams() {        return params;    }    @Override    public byte[] getBody() throws AuthFailureError {        if(entity!=null){            //文件上传            ByteArrayOutputStream bos = new ByteArrayOutputStream();            try {                entity.writeTo(bos);                return  bos.toByteArray();            } catch (IOException e) {                if(mErrorListener!=null){                    mErrorListener.onErrorResponse(new ParseError());                }                Log.e("Volley_qy","============IOException writing to ByteArrayOutputStream");            }        }        return super.getBody();    }

3.getHeaders

 @Override    public Map<String, String> getHeaders() throws AuthFailureError {        Map<String, String> headers = super.getHeaders();        if (headers == null || headers.equals(Collections.emptyMap())) {            if (header != null && !header.equals(Collections.emptyMap())) {                headers = header;            } else {                headers = new HashMap<>();            }        }        return headers;    }

4.getContentType

   @Override    public String getBodyContentType() {        if (bodyContentType == null || bodyContentType.equals("")) {            bodyContentType = super.getBodyContentType();        }        return bodyContentType;    }

5.设置 优先级

  @Override    public Priority getPriority() {        return mPriority;    }

下面看一下具体的使用
Volley使用3步骤
1.创建请求队列
2.创建request
3.将请求添加到队列里

创建请求队列

public class VolleyApplication extends Application {    public  static RequestQueue mLocalRequestQueue=null;    public  static Context context;    @Override    public void onCreate() {        super.onCreate();        context =this;    }    public static RequestQueue getmLocalRequestQueue() {        if(mLocalRequestQueue ==null){            synchronized (RequestQueue.class){                if(mLocalRequestQueue == null){                    mLocalRequestQueue = Volley.newRequestQueue(context);                }            }        }        return mLocalRequestQueue;    }}//然后在清单文件中添加这个application，还有请求网络的权限

创建request

 MyVolleyRequest request =new MyVolleyRequest(MyAPI.getTest,new VolleyResponseListener(){            @Override            public void onSuccessLoad(String string) {                mDialog.dismiss();                Log.i("TTT", "获取数据成功---1:" + string);            }            @Override            public void onFailedLoad(VolleyError error) {                Log.i("TTT", "获取数据失败---1:" );                mDialog.dismiss();            }        }, Request.Priority.NORMAL,"get1");        MyVolleyRequest request2 =new MyVolleyRequest(MyAPI.getTest,new VolleyResponseListener(){            @Override            public void onSuccessLoad(String string) {                mDialog.dismiss();                Log.i("TTT", "获取数据成功---2:" + string);            }            @Override            public void onFailedLoad(VolleyError error) {                Log.i("TTT", "获取数据失败---2:" );                mDialog.dismiss();            }        }, Request.Priority.HIGH,"get2");

添加到请求队列

 VolleyApplication.getmLocalRequestQueue().add(request); VolleyApplication.getmLocalRequestQueue().add(request2);

输出成功

获取数据成功—2:{“code”:”200”,”msg”:”获取数据成功”,”data”:[]}
获取数据成功—1:{“Data”:[{“CouponNumber”:”HYFB4GNN9U”,”CreateDate”:”2017-05-23”,”Status”:”3”}],”ErrorCode”:”200”,”ErrorMsg”:”“,”Status”:”success”}

Post请求测试

 MyVolleyRequest postRequest = new MyVolleyRequest(MyAPI.uploadImg, null, params, new VolleyResponseListener() {            @Override            public void onSuccessLoad(String string) {                mDialog.dismiss();                Log.i("yqy", "post获取数据" + string);                volleyRequestContent.setText(string);            }            @Override            public void onFailedLoad(VolleyError error) {                msg.obj = "请求服务器失败";                mDialog.dismiss();                handler.sendMessage(msg);            }        },null, "post");        VolleyApplication.getmLocalRequestQueue().add(postRequest);

输出结果： I/yqy: post获取数据{“Status”:”success”,”ErrorCode”:”200”,”ErrorMsg”:”未取到图片”,”Data”:”“}

图片上传

 Map<String, String> params = new HashMap<>();        params.put("warId", "BV67HGP4GS");        params.put("tireId", "3009971551");        params.put("k2name", "s06600008ls");        List<File> files = new ArrayList<>();        String fileName=BitmapCompressUtils.compressImage(photoUri.getPath(),30);        File f = new File(fileName);        if (f != null) {            Log.i("yqy", "文件名称" + f.getName());            files.add(f);        }        MyVolleyRequest uploadRequest = new MyVolleyRequest(MyAPI.uploadImg, null, new VolleyResponseListener() {            @Override            public void onSuccessLoad(String string) {                mDialog.dismiss();                Log.i("yqy", "上传图片成功：" + string);            }            @Override            public void onFailedLoad(VolleyError error) {                mDialog.dismiss();                Log.i("yqy", "请求失败"+error.getMessage());            }        }, params, files, "s06600008ls", null,"upload");        VolleyApplication.getmLocalRequestQueue().add(uploadRequest);

请求返回：
I/yqy: 上传图片成功：{“Status”:”success”,”ErrorCode”:”200”,”ErrorMsg”:”上传成功”,”Data”:”“}

最后，完整的一个Request

public class MyVolleyRequest extends Request<String> {    private MultipartEntity entity ;//一些带有关文件参数和读取的类    private Map<String, String> header;//请求头信息    private  VolleyResponseListener listener;    private Response.Listener<String> mListener;//请求成功的监听    private Response.ErrorListener mErrorListener;//请求错误的监听    private String bodyContentType;//文件类型    private Map<String, String> params;    private List<File> files;    private String fileName;//文件组相关的参数名称    private  int kVolleyTimeOutMS=20*1000;//超时时间    private int kVolleyMaxRetryNum =2;//超时重试时间    private Priority mPriority =Priority.NORMAL ;//设置优先级    public MyVolleyRequest(int method, String url, Response.ErrorListener listener) {        super(method, url, listener);    }    public MyVolleyRequest(String url, VolleyResponseListener listener,Request.Priority priority,String tag) {        this(Method.GET, url, listener.getmErrorListener());        this.listener = listener;        mListener = listener.getmListener();        mErrorListener = listener.getmErrorListener();        if(priority!=null){            mPriority =priority;        }        setTagAndRetryPolicy(tag,kVolleyTimeOutMS,kVolleyMaxRetryNum);    }    public MyVolleyRequest(String url, Map<String, String> header,Map<String, String> params, VolleyResponseListener listener,Request.Priority priority,String tag) {        this(Method.POST, url, listener.getmErrorListener());        this.listener = listener;        this.header = header;        mListener = listener.getmListener();        mErrorListener = listener.getmErrorListener();        this.params = params;        if(priority!=null){            this.mPriority =priority;        }        setTagAndRetryPolicy(tag,kVolleyTimeOutMS,kVolleyMaxRetryNum);    }    //上传图片    public MyVolleyRequest(String url, Map<String, String> header, VolleyResponseListener listener, Map<String, String> params, List<File> files, String fileName,Request.Priority priority,String tag) {        super(Method.POST, url, listener.getmErrorListener());        this.listener = listener;        this.header = header;        mListener = listener.getmListener();        mErrorListener = listener.getmErrorListener();        this.params = params;        this.files = files;        this.fileName = fileName;        entity=  new MultipartEntity();        bodyContentType =entity.getContentType().getValue();        buildMultipartEntity();        if(priority!=null){            this.mPriority =priority;        }    }    //设置重试和tag   public void setTagAndRetryPolicy(String tag,int timeOut,int maxRetryNum){       setTag(tag);       setRetryPolicy(new DefaultRetryPolicy(timeOut, maxRetryNum, DefaultRetryPolicy.DEFAULT_BACKOFF_MULT));   }    @Override    protected Response<String> parseNetworkResponse(NetworkResponse networkResponse) {        String parsed;        try {            parsed = new String(networkResponse.data, HttpHeaderParser.parseCharset(networkResponse.headers));        } catch (UnsupportedEncodingException var4) {            parsed = new String(networkResponse.data);        }        return Response.success(parsed, HttpHeaderParser.parseCacheHeaders(networkResponse));    }    @Override    public Map<String, String> getHeaders() throws AuthFailureError {        Map<String, String> headers = super.getHeaders();        if (headers == null || headers.equals(Collections.emptyMap())) {            if (header != null && !header.equals(Collections.emptyMap())) {                headers = header;            } else {                headers = new HashMap<>();            }        }        return headers;    }    @Override    public Priority getPriority() {        Log.i("TTT",getTag()+"==="+mPriority);        return mPriority;    }  //post请求，getparams一般不会调用,如果Request直接接触JsonRequest就会直接走getbody。但是你看源码就会发现，getbody中也会调用getParams()    @Override    public Map<String, String> getParams() {        return params;    }    @Override    public byte[] getBody() throws AuthFailureError {        if(entity!=null){            //文件上传            ByteArrayOutputStream bos = new ByteArrayOutputStream();            try {                entity.writeTo(bos);                return  bos.toByteArray();            } catch (IOException e) {                if(mErrorListener!=null){                    mErrorListener.onErrorResponse(new ParseError());                }                Log.e("Volley_qy","============IOException writing to ByteArrayOutputStream");            }        }        return super.getBody();    }    @Override    public String getBodyContentType() {        if (bodyContentType == null || bodyContentType.equals("")) {            bodyContentType = super.getBodyContentType();        }        return bodyContentType;    }    @Override    protected void deliverResponse(String s) {        Log.i("Volley_qy",getPriority()+"请求成功返回的数据是："+s);        mListener.onResponse(s);    }    // 编辑上传文件和参数的加到entity中    private void buildMultipartEntity() {        try {            if (files != null && files.size() > 0) {                for (File f : files) {                    FileBody fileBody = new FileBody(f,"image/jpeg");                    entity.addPart(fileName, fileBody);                }                long fileLength = entity.getContentLength();                Log.i("Volley_qy", "上传文件的数目是：" + files.size() + ",上传文件的长度是: " + fileLength + " byte");            }            if (params != null && params.size() > 0) {                for (Map.Entry<String, String> entry : params.entrySet()) {                    Log.i("Volley_qy", "上传文件的参数是：(" + entry.getKey() + ":" + entry.getValue() + ")");                    entity.addPart(entry.getKey(), new StringBody(entry.getValue()));                }            }        } catch (UnsupportedEncodingException e) {            VolleyLog.e("UnsupportedEncodingException");        }    }}

以上，不对的地方请指出谢谢。