Custom ArrayAdapter and Custom Layout - android-layout

Question

I am learning android programming online from udacity and this one lecture is very old and it is in Android Studio 1.0 and I am using ver 3.0.1 and that code is not working so i am trying to move with that code and have to change few thing but stuck.
Problem, I am facing is that I am trying to make custom ArrayAdapter and trying to get the custom xml layout in it but i can not find the name of my xml in the list. here are the codes so far.
Java files: CategoryAdapter.java, MainActivity.java, MainFragment.java
Layout files: activity_main.xml, fragment_main.xml, list_item_forecast.xml.
CategoryAdapter
package com.example.android.sunshine;
import android.content.Context;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
/**
* Provides the appropriate {#link Fragment} for a view pager.
*/
public class CategoryAdapter extends FragmentPagerAdapter {
/**
* Create a new {#link CategoryAdapter} object.
*
* #param mainActivity
* #param fm is the fragment manager that will keep each fragment's state in the adapter
*/
public CategoryAdapter(MainActivity mainActivity, FragmentManager fm) {
super(fm);
}
/**
* Return the {#link Fragment} that should be displayed for the given page number.
*/
#Override
public Fragment getItem(int position) {
return new MainFragment();
}
/**
* Return the total number of pages.
*/
#Override
public int getCount() {
return 1;
}
}
MainActivity
package com.example.android.sunshine;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Set the content of the activity to use the activity_main.xml layout file
setContentView(R.layout.activity_main);
// Find the view pager that will allow the user to swipe between fragments
ViewPager viewPager = (ViewPager) findViewById(R.id.viewpager);
// Create an adapter that knows which fragment should be shown on each page
CategoryAdapter adapter = new CategoryAdapter(this, getSupportFragmentManager());
// Set the adapter onto the view pager
viewPager.setAdapter(adapter);
}
}
MainFragment
package com.example.android.sunshine;
import android.content.Context;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import java.lang.reflect.Array;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import com.example.android.sunshine.R.layout;
import com.example.android.sunshine.MainFragment;
/**
* A simple {#link Fragment} subclass.
*/
public class MainFragment extends Fragment {
ArrayAdapter<String> mForecastAdapter;
public MainFragment() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
String[] forecastArry = {
"Today - Sunny - 88/63",
"Tomorrow - Foggy - 70/40",
"Wednesday - Cloudy - 72/63",
"Thursday - Asteroids - 75/65",
"Friday - Heavy Rain - 65/56",
"Saturday - Help Trapped In WeatherStation - 60/51",
"Sunday - Sunny - 80/68"
};
List<String> weekForecast = new ArrayList<String>(
Arrays.asList(forecastArry));
mForecastAdapter = new ArrayAdapter<String>(
getContext(),
R.layout.list_item_forecast,
R.id.list_item_forecast_textview,
weekForecast);
return inflater.inflate(R.layout.fragment_main, container, false);
}
}
this is where I am heaving problem
mForecastAdapter = new ArrayAdapter(getContext(), R.layout.list_item_forecast, R.id.list_item_forecast_textview, weekForecast);
I dont see list_item_forecast anywhere and it is in red. when i click on it it say create xml and when i say yes then it say already exists.
here are my xml layout codes
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.android.sunshine.MainActivity">
<android.support.v4.view.ViewPager
android:id="#+id/viewpager"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</android.support.constraint.ConstraintLayout>
fragment_main.xml
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingLeft="16dp"
android:paddingRight="16dp"
android:paddingTop="16dp"
android:paddingBottom="16dp"
tools:context=".MainActivity">
<ListView
android:id="#+id/listview_forecast"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</FrameLayout>
list_item_forecast.xml
<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:minHeight="?android:attr/listPreferredItemHeight"
android:gravity="center_vertical"
android:id="#+id/list_item_forecast_textview" />
here you can see list_item_forecast root is TextView.

Answer 1

Try to rebuild the project or create a new project and do the same. Because I did the same with Android Studio version 3.0.1 and didn't get any error.