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Android Parse - table of pointers to other tables, want to retrieve objects in the other tables

I feel like I'm pretty close on this one, just need the last bit.
I have the following tables:
_User (standard Parse table)
Category (object Id, name)
Exercises (object Id, name, description, thumbnail, image, etc)
and UserFavourites which is where I store the user's preferred exercises
(objectId, user->users table, exercise->exercises table, category->category table)
I have writing to Parse using pointers just fine:
//create new parse object
ParseObject favouriteExercise = new ParseObject("UserFavourites");
//create pointers to the Exercise table and Category table
ParseObject exercise = ParseObject.createWithoutData("Exercises", mExerciseId);
ParseObject category = ParseObject.createWithoutData("Category", mCategoryId);
//put those pointers into the Userfavourites table and save
favouriteExercise.put("user",ParseUser.getCurrentUser());
favouriteExercise.put("exercise",exercise);
favouriteExercise.put("category",category);
//save
favouriteExercise.saveInBackground();
Now I'm trying to retrieve all the exercises a user has favourited and put them in to a listview by searching the table for any objects that match the user's pointer to the user's table:
ParseQuery<Exercises> query = ParseQuery.getQuery("UserFavourites");
final ParseObject user = ParseObject.createWithoutData(ParseUser.class, ParseUser.getCurrentUser().getObjectId());
query.whereEqualTo("user", user);
//call to parse.com to start the query
query.findInBackground(new FindCallback<Exercises>() {
#Override
public void done(List<Exercises> exercises, ParseException e) {
if (exercises != null) {
Toast.makeText(getApplicationContext(), "Favourites found, can't list yet", Toast.LENGTH_SHORT).show();
mAdapter.clear();
//add all the exercises to the list
mAdapter.addAll(exercises);
//sort the list alphabetically
mAdapter.sort(new Comparator<Exercises>() {
#Override
public int compare(Exercises exercises, Exercises t1) {
return exercises.getName().compareTo(t1.getName());
}
});
} else {
mNoFavourites.setVisibility(View.VISIBLE);
}
Where I'm stuck is when I run this I can see my query is working -> I am retrieving the 4 rows in UserFavourites that I favourited out of the table of 8, so it is filtering correctly, but the objects I'm getting aren't pointing to the exercises I want. They are just empty pointers.
Thanks.

Yes it will return only reference (Pointer). If you want actual object data call fetchInBackground
myObject.fetchInBackground(new GetCallback<ParseObject>() {
public void done(ParseObject object, ParseException e) {
if (e == null) {
// Success!
} else {
// Failure!
}
}
});

I figured it out based on the logic kishore jethava gave.
I queried the favorites table, then with the results I wanted (which pointed to another table) I cycled through each result and got the object it pointed to and added it to my ArrayList.
public void getFavourites() {
//set progress bar
setProgressBarIndeterminateVisibility(true);
ParseQuery<Exercises> query = ParseQuery.getQuery("UserFavourites");
final ParseObject user = ParseObject.createWithoutData(ParseUser.class, ParseUser.getCurrentUser().getObjectId());
query.whereEqualTo("user", user);
query.include("exercise");
//call to parse.com to start the query
query.findInBackground(new FindCallback<Exercises>() {
#Override
public void done(List<Exercises> objects, ParseException e) {
if (objects.size() != 0) {
for(ParseObject object : objects)
{
//for each pointer found, retrieve the object it points to
obj = object.getParseObject("exercise");
mAdapter.add((Exercises) obj);
}
});
}
} else {
mNoFavourites.setVisibility(View.VISIBLE);
}
//stop progress bar
setProgressBarIndeterminateVisibility(false);
}
});
}

How to get only new data inserted from Parse

I'm making a small application. trying to retrieve posts inserted, and then I want to retrieve only new inserted posts, and not retrieving all the posts again.
So do you have any idea on how to I can retrieve last items ( Since the list object retrieved)
Here my Query code :
public void getFeed(int limit, int skip){
ParseQuery<ParseObject> query = ParseQuery.getQuery("Feed");
query.setSkip(skip);
query.setLimit(limit);
query.setCachePolicy(ParseQuery.CachePolicy.CACHE_ELSE_NETWORK);
query.findInBackground(new FindCallback<ParseObject>() {
public void done(List<ParseObject> feedList, ParseException e) {
if (e == null) {
for (int i = 0; i < feedList.size(); i++) {
Post p = new Post(feedList.get(i).get("Text").toString());
mAdapter.addItem(p);
}
Log.d("result", "Here is it:" + feedList.size());
mRecyclerView.setAdapter(mAdapter);
} else {
Log.d("Feed", "Error: " + e.getMessage());
}
}
});
}

keep the last time you checked and then use that time to pull anything greater than the last time checked from the createdAt column or updatedAt column (if its possible for someone to update something you are pulling) of the object. then after your query is finished update that time to the current time.

you can store the viewed posts count and next time when retrieving the list set the count as parameter for skip:
query.setSkip(count);

Getting data from Parse query

I am having some trouble getting some data from my Parse table/object with a query. I am trying to simply make a query which looks for the current Parse User's objectID in the "sender" column. When that result is returned, I want to extract the receiver's objectID from the "receiver" column associated with the user that I searched for. I keep getting 0 results, even though I know the data is there. Here is my code:
private List<String> potentialRelationQuery() {
mPotentialRelations = new ArrayList<>();
String currentUserId = mCurrentUser.getObjectId();
ParseQuery<ParseObject> query3 = ParseQuery.getQuery("PotentialRelation");
query3.whereEqualTo("sender", currentUserId);
query3.findInBackground(new FindCallback<ParseObject>() {
#Override
public void done(List<ParseObject> parseObjects, ParseException e) {
if (e == null) {
if (parseObjects.size() > 0) {
for (int i = 0; i < parseObjects.size(); i++) {
ParseUser receiver = (ParseUser) parseObjects.get(i).get("receiver");
String receiverId = receiver.getObjectId();
mPotentialRelations.add(receiverId);
}
}
} else {
Log.d("MyApp", "No matching objects returned from request");
}
}
});
return mPotentialRelations;
}

Since findInBackground is an asynchronous call to Parse isn't it possible that mPotentialRelations returns empty because the findInBackground query hasn't yet completed before the potentialRelationQuery method returns? I know I've had issues with this. Since you can't return data from an inner class (i.e. in the done method of FindCallback), writing this kind of query method has never really worked consistently for me.

Parse/Android. Getting User Associated with Object

I have an Android app that stores company names and those associated with the companies, using Parse.
I am able to get a column created called ownedby that stores the userID.
Now, I want to store information in the company column where the userID in ownedby equals the current user. Here is the query I am using:
ParseQuery<ParseObject> query = ParseQuery.getQuery("midwifefirm");
query.findInBackground(new FindCallback<ParseObject>() {
#Override
public void done(List<ParseObject> midwives, ParseException e) {
// TODO Auto-generated method stub
if(e==null) {
for (ParseObject midwifefirm : midwives) {
String midwiferelation;
ParseUser currentUser;
String userID;
midwiferelation = midwifefirm.getString("ownedby");
currentUser = ParseUser.getCurrentUser();
userID = currentUser.getObjectId();
if (midwiferelation.equals(userID)) {
midwifefirm.put("yearsinpractice", yearsexperience);
midwifefirm.put("practicename", midwifefirmname);
midwifefirm.put("education", education);
}
}
}
else{
Log.d("notretreive", "Error: " + e.getMessage());
}
}
});
This would seem to work; but in the backend, no data is stored, so I guess my "if statement" never works.
Is there anything obvious I am doing wrong? This is for a thesis project, so I can attempt to fake things a bit for the demo, but would like to learn how to do it right.
Thanks so much
Michael

Not sure I got the code below completely right. But the issue you have lies in the fact that ownedBy is a (as I understand) pointer to a User.
When you then try do midwifefirm.getString("ownedby"), you are not getting the objectId as you expect, instead you get something like {'type':'__pointer', 'class' : '_User', 'objectId' : 'xxx'} (I do not remember the notation but hope you get the idea; the literal pointer string value).
Knowing this it is not odd that an objectId xxx String never can equal midwifefirm.getString("ownedby").
Instead of getString, you can call getParseUser, which will return an empty ParseUser with the correct objectId, recall that the pointer only has the minimal information needed to retrieve the object it points to.
You should now be able to make a direct comparison between your current ParseUser and the pointer ParserUser. The fact that the latter is empty should not matter as it only needs the objectId to perform the comparison.
Try this:
ParseQuery<ParseObject> query = ParseQuery.getQuery("midwifefirm");
query.findInBackground(new FindCallback<ParseObject>() {
#Override
public void done(List<ParseObject> midwives, ParseException e) {
// TODO Auto-generated method stub
if(e==null) {
for (ParseObject midwifefirm : midwives) {
ParseUser midwiferelation;
ParseUser currentUser;
midwiferelation = midwifefirm.getParseUser("ownedby");
currentUser = ParseUser.getCurrentUser();
if (midwiferelation.equals(currentUser)) {
midwifefirm.put("yearsinpractice", yearsexperience);
midwifefirm.put("practicename", midwifefirmname);
midwifefirm.put("education", education);
}
}
}
else{
Log.d("notretreive", "Error: " + e.getMessage());
}
}
});

Parse query.whereEqualTo String issue

I am using Parse backend for my android app. I need to query the database for a record that has a field with a specific string value. following is the Parse code
strObjectId is a String initialised with a Parse ObjectId as follows
String strObjectId = MyParseObject.getObjectId();
Parse code
ParseQuery<ParseObject> query = ParseQuery.getQuery("MyDataTable");
query.whereEqualTo("code", Code);
query.getFirstInBackground(new GetCallback<ParseObject>()
{
public void done(ParseObject object, ParseException e)
{
if (object == null)
{
return;
}
else
{
ShowToast("Record found!");
}
}
});
The problem is that it works perfectly okay when 'Code' is hardcoded as follows prior to running above query
String Code = "krErZgz9Is";
But it DOES NOT work when Code is assigned Parse ObjectId as follows
String Code = strObjectId;
Obviously the Data Table does have a record with 'code' field with value 'krErZgz9Is'
Your help will be appreciated
Thanks

Have you tried to print out the strObjectId? If your object is not yet saved in Parse, or the object is not loaded from Parse. It will not have an object Id.
Also, have you tried to check the equality with the objectId directly?
query.whereEqualTo("code", MyParseObject.getObjectId());

I've got this working for me
I created an EditText and contained the text I want to find a match in my query. Just try to hide it in the layout if you don't really want to show it.
EditText editText = (EditText) findViewById(R.id.editText);
editText.setText(strObjectId);
ParseQuery<ParseObject> query = ParseQuery.getQuery("MyDataTable");
query.whereEqualTo("code", editText.getText().toString());
query.getFirstInBackground(new GetCallback<ParseObject>()
{
public void done(ParseObject object, ParseException e)
{
if (object == null)
{
return;
}
else
{
ShowToast("Record found!");
}
}
});
I don't get it why removing the getText() function doesn't work so you better keep it this way.