[android] How to set custom header in Volley Request

try this

 public void VolleyPostReqWithResponseListenerwithHeaders(String URL,final Map<String, String> params,final Map<String, String> headers,Response.Listener<String> responseListener) {


    String url = URL;

    Log.i("url:", ":" + url);
    StringRequest mStringRequest = new StringRequest(Request.Method.POST,
            url, responseListener, new Response.ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError error) {
            // error


            //Log.d("Error.Response", error.getLocalizedMessage());
        }
    }){
        @Override
        protected Map<String, String> getParams() {
            return params;
        }

        @Override
        public Map<String, String> getHeaders() throws AuthFailureError {
            return headers;
        }
    };



    mStringRequest.setRetryPolicy(new DefaultRetryPolicy(
            60000,
            DefaultRetryPolicy.DEFAULT_MAX_RETRIES,
            DefaultRetryPolicy.DEFAULT_BACKOFF_MULT));

    mStringRequest.setShouldCache(true);



    //  dialog.show();
    SingletonRequestQueue.getInstance(context).addToRequestQueue(mStringRequest);
}