Send Parse push notifications to specific users

Question

getting straight to the point, I can send push notifications from my app to other apps which have the same Channel name as it. Now my requirement is that I need to send to a particular user. Read some documentation about it but was still unclear of how to achieve that. This is what I've done so far.

Parse.initialize(this, "xxxxxxxxxxxxxxxxxxxxxxx", "yyyyyyyyyyyyyyyyyyyyy");
ParseInstallation.getCurrentInstallation().saveInBackground();
ParsePush.subscribeInBackground("words");

On Button Click:

 ParseQuery pushQuery = ParseInstallation.getQuery();
    pushQuery.whereEqualTo("user", receiver);

    ParsePush push = new ParsePush();
    push.setQuery(pushQuery);

    push.setChannel("words");
    push.setMessage(ParseUser.getCurrentUser().getUsername() + " sent you a Gift");
    push.sendInBackground();

Answer 1

删除push.setQuery(pushQuery);

Answer 2

My solution is good for you only if:

you associating every installation with user: ParseInstallation.currentInstallation.put("user",ParseUser.currentUser)

        //search all receiver users
        ParseQuery<ParseUser> userQuery = ParseUser.getQuery();
        userQuery.whereEqualTo("user", receiver);
        userQuery.findInBackground(new FindCallback<ParseUser>() {
            public void done(List<ParseUser> users, ParseException e) {
                if (users != null && users.size() > 0) {
                    //now you have all receivers
                    for (int i = 0; i < users.size(); i++) {
                        ParseUser user = users.get(i);
                        //now searching needed channel inside array of receivers
                        ArrayList<JSONObject> channels = (ArrayList<JSONObject>) user.get("channels");
                        if (channels.contains("words")){
                            //here sending the push
                            ParseQuery<ParseUser> userQuery = ParseUser.getQuery();
                            ParseQuery<ParseInstallation> installationQuery = ParseInstallation.getQuery();
                            userQuery.whereEqualTo("user", user);
                            installationQuery.whereMatchesQuery("user", userQuery);

                            ParsePush push = new ParsePush();
                            push.setQuery(installationQuery);
                            push.setMessage(ParseUser.getCurrentUser().getUsername() + " sent you a Gift");
                            push.sendInBackground();
                        }
                    }
                }
            }
        });

If your user using the same account in many devices with different channels so this is not solution for you.