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Android Build a Self-Destructing Message Android App Relating Users in Parse.com Executing a Query

alex gwartney
alex gwartney
8,849 Points
Posted by alex gwartney
alex gwartney
8,849 Points

Not sure were to place the find in background?

So im really lost on these instructions because of the way this is set up. It wants me to pass in the find in background call back after the find call back? can some one take a look and explain to me what they are wanting

CodeChallenge.java 
// This code is an excerpt from an Activity. Some code has been omitted!


 FindCallback<ParseUser> mFindCallback = new FindCallback<ParseUser>() {
    @Override
    public void done(List<ParseUser> users, ParseException e) {
        if (e == null) {

        }
    }
};

ParseQuery<ParseUser> query = ParseUser.getQuery();
query.orderByAscending("email");
alex gwartney
alex gwartney
8,849 Points
alex gwartney
alex gwartney
8,849 Points

the quiz seems to be backwards to what is taught in the video?

1 Answer

Seth Kroger
Seth Kroger
56,413 Points
Seth Kroger
Seth Kroger
56,413 Points

There are different styles of creating the callback. In the video, you write the callback as an anonymous inner class inside the function itself.

query.findInBackground(new FindCallback<ParseUser>() {
    @Override
    public void done(List<ParseUser> users, ParseException e) {
        if (e == null) {
           // Do something here...
        }
    });

However that new FindCallback<ParseUser>() {} can be stored in a variable as well which can then be used in the findInBackground(). This other style is what the challenge uses. If you have more than one findInBackground() call in you code that uses the same callback code, you can simply reference the variable instead of rewriting the callback every time.

alex gwartney
alex gwartney
8,849 Points
alex gwartney
alex gwartney
8,849 Points

I figured it out thanks for the explanation i was looking at in the wrong way.