how to get email id from facebook sdk in android applications?

Solution 1:

Before calling Session.openActiveSession do this to get permissions add this:

List<String> permissions = new ArrayList<String>();
permissions.add("email");

The last parameter in Session.openActiveSession() should be permissions. Now you can access user.getProperty("email").toString().

EDIT:

This is the way I am doing facebook authorization:

List<String> permissions = new ArrayList<String>();
permissions.add("email");

loginProgress.setVisibility(View.VISIBLE);

//start Facebook session
openActiveSession(this, true, new Session.StatusCallback() {
    @Override
    public void call(Session session, SessionState state, Exception exception) {
        if (session.isOpened()) {
            //make request to the /me API
            Log.e("sessionopened", "true");
            Request.executeMeRequestAsync(session, new Request.GraphUserCallback() {
                @Override
                public void onCompleted(GraphUser user, Response response) {
                    if (user != null) {
                        String firstName = user.getFirstName();
                        String lastName = user.getLastName();
                        String id = user.getId();
                        String email = user.getProperty("email").toString();

                        Log.e("facebookid", id);
                        Log.e("firstName", firstName);
                        Log.e("lastName", lastName);
                        Log.e("email", email);
                    }
                }
            });
         }
     }
 }, permissions);

Add this method to your activity:

private static Session openActiveSession(Activity activity, boolean allowLoginUI, Session.StatusCallback callback, List<String> permissions) {
    Session.OpenRequest openRequest = new Session.OpenRequest(activity).setPermissions(permissions).setCallback(callback);
    Session session = new Session.Builder(activity).build();
    if (SessionState.CREATED_TOKEN_LOADED.equals(session.getState()) || allowLoginUI) {
        Session.setActiveSession(session);
        session.openForRead(openRequest);
        return session;
    }
    return null;
}

Solution 2:

Following the suggestion of Egor N, I change my old code

Session.openActiveSession(this, true, statusCallback);

whith this new one:

List<String> permissions = new ArrayList<String>();
permissions.add("email");
Session.openActiveSession(this, true, permissions, statusCallback);

Now FB ask the user about the permission of email and I can read it in the response.