Situação:

Eu tenho um widget de visualização de pesquisa na barra de ferramentas do appcompat que permite sugestões personalizadas via sqlitedatabase.

Problema:

Estou com problemas para expandir a lista suspensa de sugestões para ter toda a largura da tela. Na melhor das hipóteses, a largura da lista é quase a largura da tela, exceto por pequenos problemas de margem / preenchimento no lado esquerdo e direito. Como faço para que a lista suspensa tenha a mesma largura da tela?

Coisas que tentei:

Visualizar largura da lista de resultados

SetPadding, setRight / setLeft, setDropDownHorizontalOffset do AutoCompleteText, definindo parâmetros de layout e definindo a largura como match_parent.

menu / search.xml

<item
    android:id="@+id/search_restaurant"
    android:title="Search"
    android:icon="@drawable/search"
    android:orderInCategory="2"
    app:actionViewClass="android.support.v7.widget.SearchView"
    app:showAsAction="always"/>

res / search_view_suggestions_list_item

<TextView
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@android:id/text1"
    android:layout_width="match_parent"
    android:layout_height="48dp"
    android:textAppearance="?android:attr/textAppearanceListItemSmall"
    android:background="@android:color/white"
    android:gravity="center_vertical"
    android:paddingLeft="16dp"
    android:paddingRight="16dp"
    android:minHeight="?android:attr/listPreferredItemHeightSmall"/>

activity / Activity.java

    MenuItem searchItem = menu.findItem(R.id.search_restaurant);
    searchView = (SearchView) MenuItemCompat.getActionView(searchItem);
    searchView.setQueryHint("Search Restaurant");
    searchView.setOnQueryTextListener(this);
    searchView.setOnSuggestionListener(this);
    final AutoCompleteTextView searchAutoCompleteTextView = (AutoCompleteTextView) searchView
            .findViewById(R.id.search_src_text);
    searchAutoCompleteTextView.setThreshold(1);
    searchAutoCompleteTextView.setDropDownWidth(ViewGroup.LayoutParams.MATCH_PARENT);

    // Tried to change margins/padding here
    LinearLayout.LayoutParams params = (LinearLayout.LayoutParams)
            searchAutoCompleteTextView.getLayoutParams();
    params.setMargins(0, 0, 0, 0);
    searchAutoCompleteTextView.setLayoutParams(params);
    searchAutoCompleteTextView.setPadding(0, 0, 0, 0);

    searchAutoCompleteTextView.setDropDownHorizontalOffset(-100);
    searchAutoCompleteTextView.setPadding(0,0,0,0);
    searchAutoCompleteTextView.setLeft(0);

    final View dropDownSuggestions = searchView.findViewById(searchAutoCompleteTextView
            .getDropDownAnchor());
    if (dropDownSuggestions != null) {
        dropDownSuggestions.addOnLayoutChangeListener(new View.OnLayoutChangeListener() {
            @Override
            public void onLayoutChange(View v, int left, int top, int right, int bottom, int oldLeft, int oldTop, int oldRight, int oldBottom) {
                int point[] = new int[2];

                dropDownSuggestions.getLocationOnScreen(point);
                int dropDownPadding = point[0] + searchAutoCompleteTextView
                        .getDropDownHorizontalOffset();

                Rect screenSize = new Rect();
                getWindowManager().getDefaultDisplay().getRectSize(screenSize);
                int screenWidth = screenSize.width();
                searchAutoCompleteTextView.setDropDownWidth(screenWidth * 2);
            }
        });
    }