Parse Nested Query Android

Question

Ok been stuck on this for literally weeks, sorry for long question.

Using Parse, making a workout app for Android.

Database tables and columns that are relevant to my problem are:

Exercises

ID| name | description | Musclegroup

Workouts

ID| workoutName| userID

WorkoutExercises (basically a join table between the two)

ID| workoutID (pointer) | exerciseID (pointer)

So a user will be able to create a workout and add in the exercises they want.

So far I've already done:

• User can go to category, browse the muscle group, view the exercises in that group
• signup/login/logout, update profile
• list the current workouts (not the exercises in them) - I have just entered some exercises into a workout on the db as have gotten stuck on querying current exercises in that workout before worrying about inserting new ones.

The problem:

I'm trying to do a nested query to get the exercise name so once a user clicks Eg. Back Workout it should bring up a list Eg. Deadlift, Rows, Chin ups

So basically in SQL I want to:

Select name from Exercises where ID in (select exerciseID from workoutexercises where WorkoutID=xxxx)

Things i'm struggling on:

1. Making a nested query for a pointer, from what I have read on the net I need to use query.include("exerciseID"); which will tell Parse to include a full Exercise item that I can then use to query? Correct me if wrong? Code below - have I done it correctly?

2. I've learnt from and been using methods from: http://www.michaelevans.org/blog/2013/08/14/tutorial-building-an-android-to-do-list-app-using-parse/ where query data is put into a custom adapter that lists the data. It uses getters and setters to save/retrieve String/int values, do I still use the getters for getting a string from within a pointer?

EG.

public String getName()
    {
        return getString("name");
    }

As in once i'm "through" that pointer and in the Exercise table im assuming i'm still just getting the String name value as oppose to getting a ParseObject?

Now so far I have been able to get the custom adapter to put 2 horizontal bars across the screen that shows it knows i've put 3 items in workoutExercises but just not bringing up the text from Exercise name that I need from the nested query

Have a look at my screenshots to see what I mean.

Thank you very much for the help in advance.

Query so far:

    public void getcurrentExercisesInWorkout() {
    //set progress bar
    setProgressBarIndeterminateVisibility(true);
    ParseQuery<WorkoutExercises> query = ParseQuery.getQuery("WorkoutExercises");
    query.include("exerciseId");
    query.whereEqualTo("workoutId", mWorkoutId);

    query.findInBackground(new FindCallback<WorkoutExercises>() {
        @Override
        public void done(List<WorkoutExercises> workoutExercises, ParseException error) {
            if (workoutExercises != null) {

                mWorkoutExercisesAdapter.clear();
                mWorkoutExercisesAdapter.addAll(workoutExercises);

            } else {
                Log.d("error", error.getMessage());
            }
        }
    });
    //stop progress bar
    setProgressBarIndeterminateVisibility(false);
}

Custom list Adapter:

//constructor - get current state of parsed object and list of objects retrieved from workout
public WorkoutExercisesAdapter(Context context, List<WorkoutExercises> objects) {
    super(context, R.layout.row_item, objects);
    this.mContext = context;
    this.mWorkoutExercises = objects;
}
public View getView(int position, View convertView, ViewGroup parent)
{
    //put each item into the listview
    if(convertView == null)
    {
        LayoutInflater mLayoutInflater = LayoutInflater.from(mContext);
        convertView = mLayoutInflater.inflate(R.layout.row_item,null);
    }
    WorkoutExercises workoutExercises = mWorkoutExercises.get(position);

    TextView nameView = (TextView) convertView.findViewById(R.id.row_name);
    //this just calls a String getter - which isn't working - need it to get the Exercise name from within the pointer
    nameView.setText(workoutExercises.getWorkoutExercise());
    return convertView;
}

WorkoutExercises(stores the getters)

    @ParseClassName("WorkoutExercises")
public class WorkoutExercises extends ParseObject {
    public String exName;
    public WorkoutExercises()
    {
    }
    public String getWorkoutExercise()
    {
        return getString("name");
    }
}

Running Android Studio in Debug mode I can literally see the data I am trying to put into the text field (see screenshot - how can I grab that value? See screenshot below

NOW WORKING - THE RESULT!

Answer 1

First, alter the WorkoutExercises object:

@ParseClassName("WorkoutExercises")
public class WorkoutExercises extends ParseObject {
    //public String exName;
    public static final String workoutID = "workoutID" 
    public static final String exerciseID = "exerciseID" 

    public Exercises getWorkoutExercise() {
        return (Exercises)getParseObject(exerciseID);
    }

    public WorkoutExercises()
    {
        // not sure if it is allowed to define your own constructor?
        // just a note
    }

    // WorkoutExercises does not have a 'name' col
    //public String getWorkoutExercise()
    //{
    //    return getString("name");
    //}
}

I assume that Exercises at least contains something like:

@ParseClassName("Exercises")
public class Exercises extends ParseObject {

    public static final String name = "name" 


    public String getName()
    {
        return getString(name);
    }

}

Now, with the query on WorkoutExercises including workoutID, the Exercises object will be populated in the fetched query. This means you can do the following to get the name of the exercises object:

// workoutExercises returned from a query including workoutID
Exercises exercise = workoutExercises.getWorkoutExercise();
String name = exercise.getName();

// if Exercises has getters for description and Musclegroup
String description = exercise.getDescription();
String musclegroup= exercise.getMusclegroup();

Hope this sheds some light on the problem