layout_list.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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:padding="10dp"
    >

    <TextView
        android:id="@+id/nom"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="@android:color/black"
        android:layout_marginLeft="10dp"
        android:textStyle="bold"
        tools:text="Nom"
        />

</RelativeLayout>

Level.java

package eni.baptistedixneuf.fr.sudoku.bo;

import android.os.Parcel;
import android.os.Parcelable;

/**
 * Created by bdixneuf2015 on 28/04/2017.
 */
public class Level implements Parcelable {

    private int id;
    private String nom;

    public Level(){}

    protected Level(Parcel in){
        id = in.readInt();
        nom = in.readString();
    }

    public static final Parcelable.Creator<Level> CREATOR =  new Parcelable.Creator<Level>(){

        @Override
        public Level createFromParcel(Parcel source) {

            return new Level(source);
        }

        @Override
        public Level[] newArray(int size) {
            return new Level[size];
        }
    };

    public void writeToParcel(Parcel dest, int flags) {
        dest.writeInt(id);
        dest.writeString(nom);
    }

    public int describeContents() {
        return 0;
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getNom() {
        return nom;
    }

    public void setNom(String nom) {
        this.nom = nom;
    }


}

LevelAdapter.java

package eni.baptistedixneuf.fr.sudoku.adapter;

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 java.util.List;

import eni.baptistedixneuf.fr.sudoku.R;
import eni.baptistedixneuf.fr.sudoku.bo.Level;

/**
 * Created by bdixneuf2015 on 28/04/2017.
 */
public class LevelAdapter extends ArrayAdapter<Level> {

    //tweets est la liste des models à afficher
    public LevelAdapter(Context context, List<Level> levels) {
        super(context, 0, levels);
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {

        if(convertView == null){
            convertView = LayoutInflater.from(getContext()).inflate(R.layout.level_list,parent, false);
        }

        LevelViewHolder viewHolder = (LevelViewHolder) convertView.getTag();
        if(viewHolder == null){
            viewHolder = new LevelViewHolder();
            viewHolder.nom = (TextView) convertView.findViewById(R.id.nom);
            convertView.setTag(viewHolder);
        }

        //getItem(position) va récupérer l'item [position] de la List<Tweet> tweets
        Level level = getItem(position);

        //il ne reste plus qu'à remplir notre vue
        viewHolder.nom.setText(level.getNom());
        return convertView;
    }

    private class LevelViewHolder {
        public TextView nom;
    }
}

Main.java

 //On rafraichit la liste
        LevelAdapter adapter = new LevelAdapter(MainActivity.this, levels);
        mListView = (ListView) findViewById(R.id.listView);
        mListView.setAdapter(adapter);