Volley - POST/GET parameters

Asked 18/5, 2013 at 15:41 Answered 16/5, 2018 at 16:53

Solved android networking android-volley

I saw Google IO 2013 session about Volley and I'm considering switching to volley. Does Volley support adding POST/GET parameters to request? If yes, how can I do it?

Heathcote answered 18/5, 2013 at 15:41 Comment(4)

I didn't see the whole keynote, but I'm pretty sure the GET should be doable just by adding the parameters to the URL (eg. http://example.com?param1=val1&param2=val2) – Coben 19/5, 2013 at 9:45

There seems to be no documentation yet, but you can check the source here android.googlesource.com/platform/frameworks/volley/+/master – Obstetrics 19/5, 2013 at 18:9

@JJ56 - Right, but what about POST parameters? I saw source code but didn't find anything related to POST parameters. – Heathcote 19/5, 2013 at 19:49

I feel ashamed to say this. But, If you get here asking why your request doesn't have a body on your server, make sure you're using POST/PUT method. Guess I'm just tired. Hope this comment helps anybody or helps me feel better – President 16/3, 2018 at 1:37

In your Request class (that extends Request), override the getParams() method. You would do the same for headers, just override getHeaders().

If you look at PostWithBody class in TestRequest.java in Volley tests, you'll find an example. It goes something like this

public class LoginRequest extends Request<String> {

    // ... other methods go here

    private Map<String, String> mParams;

    public LoginRequest(String param1, String param2, Listener<String> listener, ErrorListener errorListener) {
        super(Method.POST, "http://test.url", errorListener);
        mListener = listener;
        mParams = new HashMap<String, String>();
        mParams.put("paramOne", param1);
        mParams.put("paramTwo", param2);

    }

    @Override
    public Map<String, String> getParams() {
        return mParams;
    }
}

Evan Charlton was kind enough to make a quick example project to show us how to use volley. https://github.com/evancharlton/folly/

Jongjongleur answered 19/5, 2013 at 21:0 Comment(10)

Notice that the getParams is only called (by default) in a POST or PUT request, but not in a GET request. See Ogre_BGR's answer – Interblend 29/8, 2013 at 10:44

Can't believe I never noticed that until now – Jongjongleur 29/8, 2013 at 16:3

@AfzalivE, any idea about how to sign API request with OAuth when using above code? – Amphicoelous 1/10, 2013 at 13:17

@BipinVayalu If you are connecting to Google API you should be able to use com.android.volley.AndroidAuthenticator – Dichroscope 7/12, 2013 at 15:52

You forgot to instantiate mParams. – Gasometer 15/8, 2014 at 10:38

Lol, probably because I was really excited to answer this question. Fixed. – Jongjongleur 15/8, 2014 at 18:41

It won't work if you need to pass the same key with multiple values, like id=1&id=2&id=3. To do it you need to use com.google.common.collect.Multimap and Override the getBody method instead of the getParams method. – Subduct 16/4, 2015 at 13:47

@ItaiHanski any idea how to get response code to a post request in which paramters are also passed? – Waldenses 10/2, 2017 at 7:28

@Harsha Ognyan's answer covers that – Jongjongleur 2/8, 2017 at 16:8

why "cannot resolve symbol map"? please help, thanks – Bobbyebobbysocks 5/1, 2018 at 15:30

For the GET parameters there are two alternatives:

First: As suggested in a comment bellow the question you can just use String and replace the parameters placeholders with their values like:

String uri = String.format("http://somesite.com/some_endpoint.php?param1=%1$s&param2=%2$s",
                           num1,
                           num2);

StringRequest myReq = new StringRequest(Method.GET,
                                        uri,
                                        createMyReqSuccessListener(),
                                        createMyReqErrorListener());
queue.add(myReq);

where num1 and num2 are String variables that contain your values.

Second: If you are using newer external HttpClient (4.2.x for example) you can use URIBuilder to build your Uri. Advantage is that if your uri string already has parameters in it it will be easier to pass it to the URIBuilder and then use ub.setQuery(URLEncodedUtils.format(getGetParams(), "UTF-8")); to add your additional parameters. That way you will not bother to check if "?" is already added to the uri or to miss some & thus eliminating a source for potential errors.

For the POST parameters probably sometimes will be easier than the accepted answer to do it like:

StringRequest myReq = new StringRequest(Method.POST,
                                        "http://somesite.com/some_endpoint.php",
                                        createMyReqSuccessListener(),
                                        createMyReqErrorListener()) {

    protected Map<String, String> getParams() throws com.android.volley.AuthFailureError {
        Map<String, String> params = new HashMap<String, String>();
        params.put("param1", num1);
        params.put("param2", num2);
        return params;
    };
};
queue.add(myReq);

e.g. to just override the getParams() method.

You can find a working example (along with many other basic Volley examples) in the Andorid Volley Examples project.

Minyan answered 28/5, 2013 at 15:25 Comment(12)

I've followed your examples of Volley. So far it's the most helpful Volly code, but I've an issues in JsonObjectRequest. I got the old response in createMyReqSuccessListener until I reinstall it again. Is volley store data in cache? Please suggest a way to do this. – Ifill 16/1, 2014 at 14:2

Only images are cached. Please check if there is some proxy is intercepting your requests. If the requests has exactly the same URL and it is possible that the proxy is simply returning the first result. – Minyan 16/1, 2014 at 14:23

May be you are right. But how to solve that? Is putting "header("Cache-Control: no-cache"); in the php file.." this line will help? – Ifill 16/1, 2014 at 14:28

There is a plugin for Firefox called "HTTP resource test" that allows you to send requests agains web server. It is quite useful for testing cases like this. Just enter your URL (and POST parameters if any) and see what is the response of the server for multiple consecutive requests. If again you get the same response result is most probably cached. In that case you may examine the returned headers to check if there are proxy headers. About the "no-cache" - yes, it should work. – Minyan 16/1, 2014 at 14:34

I've checked it in "HTTP resource test" add on, I can see new response every time I post the url. So the problem is in the app, probably the structure I'm following to call the volley request. As I said reinstalling the app does the work. I've also put the "no-cache" header to api file. – Ifill 17/1, 2014 at 6:12

I suggest that you open separate question so others can join and help.Please provide info what stack are you using HURL or HttpClient, also the android version that are you testing against. Please, put a link to the new question here so people can follow the discussion. – Minyan 17/1, 2014 at 8:30

Sorry for late replying. I found that the problem is with Genymotion, it's working fine in avd and in Nexus 7. Thanks! – Ifill 21/1, 2014 at 5:37

Any idea why volley does not call getParams() for GET request? Is there some specification restriction? I would appreciate if I does not have to manually construct and escape URI. Parse/prepare parameters in getParams() method seems logical to me. – Ingold 9/6, 2015 at 11:33

@Ogre_BGR, What the difference between Method.GET and Method.POST?, I'm using only Method.GET even for sending parms to the server, Is it bad? – Laudable 4/7, 2015 at 5:8

@Laudable Probably you will get a lot better answers if you ask this as new question, but in short: POST request allows you to send files and other bigger data that will not fit in GET request. Also there is a security risk when using GET request because the URL may get logged on the server thus exposing sensitive data. – Minyan 4/7, 2015 at 10:14

i still do not "GET" how have you made the String uri, can i not just append the values of param1 and param2? is it necessary to provide the other parameter like num1 and num2 still? – Partheniaparthenocarpy 4/9, 2015 at 12:14

@Ogre_BGR: Are the parameters encoded automatically? – Trona 13/11, 2015 at 10:46

In your Request class (that extends Request), override the getParams() method. You would do the same for headers, just override getHeaders().

If you look at PostWithBody class in TestRequest.java in Volley tests, you'll find an example. It goes something like this

public class LoginRequest extends Request<String> {

    // ... other methods go here

    private Map<String, String> mParams;

    public LoginRequest(String param1, String param2, Listener<String> listener, ErrorListener errorListener) {
        super(Method.POST, "http://test.url", errorListener);
        mListener = listener;
        mParams = new HashMap<String, String>();
        mParams.put("paramOne", param1);
        mParams.put("paramTwo", param2);

    }

    @Override
    public Map<String, String> getParams() {
        return mParams;
    }
}