I want to add a button at the bottom of the list of apps.

<RelativeLayout>
  <ImageView/>
  <TextView/>
  <TextView/>
</RelativeLayout>

<LinearLayout>
  <ListView/>
  <Button/>
</LinearLayout>

public class LancherApp extensions Activity {

    //
    private ArrayList<String>items=null;
    //
    private ApplicationListAdapter adapter = null;

    @ Override
    protected void onCreate (Bundle bundle) {
        super.onCreate(bundle);
        requestWindowFeature(Window.FEATURE_NO_TITLE);

        setContentView(R.layout.activity_main);
        // create String Arraylist.
        List<AppData>appList=new ArrayList<AppData>();
        // create PackageManager.
        PackageManager packageManager=getPackageManager();
        // make application list in your device has already installed.
        final List <ApplicationInfo>installedAppList=packageManager.getInstalledApplications (PackageManager.GET_META_DATA);

        for (ApplicationInfo app:installedAppList) {
            AppData data = new AppData();
            data.label=app.loadLabel(packageManager).toString();
            data.icon=app.loadIcon(packageManager);
            data.name=app.packageName;
            appList.add(data);
        }

        finalListView listView=(ListView) findViewById (R.id.list);
        adapter = new ApplicationListAdapter(this,appList);
        listView.setAdapter(adapter);
    }

    // private adapter class indicators label and icon of application.
    private static class ApplicationListAdapter extensions ArrayAdapter <AppData>{
        //
        private final LayoutInflater mInflater;

        public ApplicationListAdapter (Context context, List<AppData>dataList) {
            super(context,R.layout.list_item);
            mInflater= (LayoutInflater) 
            context.getSystemService(context.LAYOUT_INFLATER_SERVICE);
            addAll(dataList);
        }

        @ Override
        publicView getView(int position, View convertView, ViewGroup parent) {
            ViewHolder holder = new ViewHolder();

            if(convertView==null){
                convertView=mInflater.inflate(R.layout.list_item, parent, false);
                holder.textLabel=(TextView) convertView.findViewById(R.id.label);
                holder.imageIcon=(ImageView)convertView.findViewById(R.id.icon);
                holder.packageName=(TextView) convertView.findViewById(R.id.name);
                convertView.setTag(holder);
            } else{
                holder=(ViewHolder)convertView.getTag();
            }

            //
            final AppData data=getItem(position);
            //
            holder.textLabel.setText(data.label);
            holder.imageIcon.setImageDrawable(data.icon);
            holder.packageName.setText(data.name);

            return convertView;
        }
    }

    // private class for storage application data.
    private static class AppData{
        String label;
        Drawable icon;
        String name;
    }

    // private class ViewHolder.
    private static class ViewHolder {
        TextView textLabel;
        ImageView imageIcon;
        TextView packageName;
    }
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android: orientation="vertical">

    <ListView
        android: id="@+id/list"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1"/>

    <Button
        android: id="@+id/button4"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Button"/>

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android: orientation="vertical">

    <ImageView
        android: id="@+id/icon"
        android:layout_width="50dp"
        android:layout_height="50dp"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:layout_weight="1"/>

    <TextView
        android: id="@+id/label"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:layout_alignParentTop="true"
        android:layout_toRightOf="@+id/icon"
        android:textSize="18sp"
        android:layout_weight="1"/>

    <TextView
        android: id="@+id/name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/label"
        android:layout_alignParentRight="true"
        android:layout_below="@+id/label"
        android:layout_weight="1"/>

</RelativeLayout>