Android Studio, Parse.com, custom adapter, cannot resolve symbol - parse-platform

Question

I am new in creating apps. I am learning by doing courses on Udemy. So right now I am learning how to create a simple app where your can register, login and post a message, and I am doing all of this using Parse.com. Everything worked perfectly until today, when it was time to create a custom adapter that shows these posts.
The error is: cannot resolve symbol mStatus in the HomepageActivity class, though in the Udemy video, everything works perfectly.
Another strange error is in the line
ParseQuery<ParseObject> query = new ParseQuery <ParseObject> ("Status");
the second <ParseObject> is greyed out and it says Explicit type argument can be replaced with <>, though in the video its white(working).
The only explanation I thought of is that the video is old and something changed in the syntax, but I am not that great of a programmer to understand what to do. Or maybe im doing something wrong? Please help.
P.S . when I am trying to run the app, I am getting this message:
Note:C:\Users\User\AndroidStudioProjects\LiveUpdate\app\src\main\java\com\mycompany\liveupdate\StatusAdapter.java uses unchecked or unsafe operations.
Here is the adapter code:
package com.mycompany.liveupdate;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;
import com.parse.ParseObject;
import java.util.List;
/**
* Created by User on 2015-01-18.
*/
public class StatusAdapter extends ArrayAdapter {
protected Context mContext;
protected List<ParseObject> mStatus;
public StatusAdapter(Context context, List status) {
super(context, R.layout.homepagecustomlayout, status);
mContext = context;
mStatus = status;
}
#Override
public View getView(final int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = LayoutInflater.from(mContext).inflate(
R.layout.homepagecustomlayout, null);
holder = new ViewHolder();
holder.usernameHomepage = (TextView) convertView
.findViewById(R.id.usernameHP);
holder.statusHomepage = (TextView) convertView
.findViewById(R.id.statusHP);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
ParseObject statusObject = mStatus.get(position);
// title
String username = statusObject.getString("user");
holder.usernameHomepage.setText(username);
// content
String status = statusObject.getString("newStatus");
holder.statusHomepage.setText(status);
return convertView;
}
public static class ViewHolder {
TextView usernameHomepage;
TextView statusHomepage;
}
}
Here is the code, where im trying to call this adapter:
package com.mycompany.liveupdate;
import android.app.ListActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import com.parse.FindCallback;
import com.parse.Parse;
import com.parse.ParseException;
import com.parse.ParseObject;
import com.parse.ParseQuery;
import com.parse.ParseUser;
import java.util.List;
public class HomepageActivity extends ListActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_homepage);
Parse.initialize(this, "uinXCHcfbdm8zrbUT9y8Vu4R2qU5D22FZwkHs5HZ", "v1PL4oDu3ebtSidJFhjWRkkBQVAD8sefIB1WDFeq");
ParseUser currentUser = ParseUser.getCurrentUser();
if (currentUser != null) {
// show user the homepage
ParseQuery<ParseObject> query = new ParseQuery<ParseObject>("Status");
query.orderByDescending("createdAt");
query.findInBackground(new FindCallback<ParseObject>() {
#Override
public void done(List<ParseObject> status, ParseException e) {
if(e == null){
//success
mStatus = status;
StatusAdapter adapter = new StatusAdapter(getListView().getContext(), status);
setListAdapter(adapter);
}else {
//there was a problem
}
}
});
} else {
// show the signup or login screen
Intent takeUserToLogin = new Intent(HomepageActivity.this, LogInActivity.class);
startActivity(takeUserToLogin);
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_homepage, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
switch (id){
case R.id.updateStatus:
//take user to updatestatus activity
Intent intent = new Intent(this, UpdateStatusActivity.class );
startActivity(intent);
break;
case R.id.logoutUser:
// log out user
ParseUser.logOut();
// take the user back to logout screen
Intent takeUserToLogin = new Intent(this, LogInActivity.class);
startActivity(takeUserToLogin);
break;
}
return super.onOptionsItemSelected(item);
}
}