Problem with Gridview shows com.mac.fablab.fablab.Objetocurso@53683d4c

I have a problem with the ArrayAdapter inside a Fragment, apparently if I display the number of objects inside my ArrayList but it shows me the following:

This is my Fragement_2.Java file

public class Fragment_2 extends Fragment {
List proyectos;
private GridView mGridView;
private GridCursoAdapter mAdapter;
private ArrayList<ObjetoCurso> listaCursos;


// Argumento del Fragment_2 que representa el número de sección
public static final String ARG_FRAGMENT_2 = "section_number_2";

public Fragment_2() {
}


@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {

    View rootView = inflater.inflate(R.layout.fragment2, container,
            false);
    listaCursos = new ArrayList<ObjetoCurso>();

    mGridView = (GridView) rootView.findViewById(R.id.gridCursos);
    llenarListaCursos();
    ArrayAdapter<ObjetoCurso> adapter = new ArrayAdapter<ObjetoCurso>(getActivity(), android.R.layout.simple_list_item_1, listaCursos);
    mGridView.setAdapter(adapter);

    //setupAdapter();

    return rootView;
}
public void llenarListaCursos(){
    for(int i = 0; i < 20 ; i++){
        ObjetoCurso obj = new ObjetoCurso("PROGRAMACION EN ANDROID",R.drawable.fotoperfil);
        listaCursos.add(i, obj);
    }
}



}

This is my fragment2.xml file

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.mac.fablab.fablab.Fragment_2">

<GridView
    android:id="@+id/gridCursos"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:numColumns="3"/>

</RelativeLayout>

This is my grid_view_item.xml file

<android.support.design.widget.CoordinatorLayout 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.mac.fablab.fablab.grid_view_item">

<android.support.design.widget.AppBarLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:theme="@style/AppTheme.AppBarOverlay">

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        android:background="?attr/colorPrimary"
        app:popupTheme="@style/AppTheme.PopupOverlay" />

</android.support.design.widget.AppBarLayout>

<include layout="@layout/content_grid_view_item" />

<android.support.design.widget.FloatingActionButton
    android:id="@+id/fab"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="bottom|end"
    android:layout_margin="@dimen/fab_margin"
    app:srcCompat="@android:drawable/ic_dialog_email" />

</android.support.design.widget.CoordinatorLayout>

This is my class ObjectCourse.Java

public class ObjetoCurso{
 String c_nombre;
 int c_portada;

public ObjetoCurso(String c_nombre, int c_portada) {
    this.c_nombre = c_nombre;
    this.c_portada = c_portada;
}

public String getC_nombre() {
    return c_nombre;
}

public void setC_nombre(String c_nombre) {
    this.c_nombre = c_nombre;
}

public int getC_portada() {
    return c_portada;
}

public void setC_portada(int c_portada) {
    this.c_portada = c_portada;
}
}

This is my adapter for the GridView GridViewAdapter.Java

public class GridCursoAdapter extends ArrayAdapter<ObjetoCurso>{

private Context context;
private ArrayList<ObjetoCurso> mDataset = new ArrayList<>();
@Override
public int getCount() {
    return 0;
}
public GridCursoAdapter(Context context,int textViewResourceId, ArrayList<ObjetoCurso> myDataset) {
    super(context, textViewResourceId, myDataset);
    mDataset = myDataset;
}
@Override
public ObjetoCurso getItem(int i) {
    return mDataset.get(i);
}


@Override
public long getItemId(int i) {
    return 0;
}

@Override
public View getView(int position, View view, ViewGroup viewGroup) {


    View v = view;
    LayoutInflater inflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    v = inflater.inflate(R.layout.grid_view_item, null);
    TextView textView = (TextView) v.findViewById(R.id.c_nombre);
    ImageView imageView = (ImageView) v.findViewById(R.id.c_portada);
    ObjetoCurso obj = getItem(position);
    textView.setText("HOLA");
    imageView.setImageResource(R.drawable.fotoperfil);
    return v;


}


}