Call facebook graphrequest multiple times - facebook

Question

i'm developpig an app in which i need to call the fb graphrequest multiple times , but those calls needs to be one after the other, the first one will get me the user friends, and the other calls will be done in a loop (for each friend ) get the "likes" that that friend made, now with the code that i made, the first one gives me the friends but the second one (the loop instruction) won't work, i guess it has somehing to do with the async calls but i don't know how to make them serial calls, here's my code :
GraphRequest request = GraphRequest.newMyFriendsRequest(
AccessToken.getCurrentAccessToken(),
new GraphRequest.GraphJSONArrayCallback() {
#Override
public void onCompleted(JSONArray array, GraphResponse response) {
JSONObject jsonArray = response.getJSONObject();
try {
length = jsonArray.getJSONArray("data").length();
for (int i = 0; i < length; i++) {
AlertDialog a = new AlertDialog.Builder(liste_peronalisee.this).create();
a.setTitle("Erreur");
id[i] = jsonArray.getJSONArray("data").getJSONObject(i).getString("id");
a.setMessage(id[i]);
a.show();
}
} catch (JSONException e) {
e.printStackTrace();
}
}
});
request.executeAsync();
for(int i=0;i<id.length;i++)
request = GraphRequest.newGraphPathRequest(
AccessToken.getCurrentAccessToken(),
"/".concat(id[i]).concat("/likes"),
new GraphRequest.Callback() {
#Override
public void onCompleted(GraphResponse response) {
JSONObject jsonArray = response.getJSONObject();
try {
length = jsonArray.getJSONArray("data").length();
for (int i = 0; i < length; i++) {
AlertDialog a = new AlertDialog.Builder(liste_peronalisee.this).create();
a.setTitle("Erreur");
id[i] = jsonArray.getJSONArray("data").getJSONObject(i).getString("name");
a.setMessage(id[i]);
a.show();
}
} catch (JSONException e) {
e.printStackTrace();
}
}
});
request.executeAsync();
i need a quick answer, thanks in advance