Android: Spinner with hint text and "setError" like functionality

Adapter:

public class GenderAdapter extends BaseAdapter {

    private Context context;
    private String[] genderList;

    public GenderAdapter(Context context) {
        this.context = context;
        this.genderList = new String[3];
        this.genderList[0] = context.getString(R.string.gender); // Hint text
        this.genderList[1] = context.getString(R.string.male);
        this.genderList[2] = context.getString(R.string.female);
    }

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

        if (convertView == null) {
            convertView = LayoutInflater.from(context).inflate(R.layout.drop_down_row_light_gray, null);
        }

        TextView text = (TextView) convertView.findViewById(R.id.text);
        text.setText(getItem(position));

        Resources resources = context.getResources();
        text.setTextColor(resources.getColor(position == 0 ? R.color.gray : R.color.dark_gray)); // If it is the hint text (position == 0) set the textcolor to be a lighter color


        return convertView;
    }

    @Override
    public int getCount() {
        return genderList.length;
    }

    @Override
    public String getItem(int position) {
        return genderList[position];
    }

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

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

        if (convertView == null) {
            convertView = LayoutInflater.from(context).inflate(R.layout.closed_row_light_gray, null);
        }

        TextView text = (TextView) convertView.findViewById(R.id.text);
        text.setText(getItem(position));

        Resources resources = context.getResources();
        text.setTextColor(resources.getColor(position == 0 ? R.color.gray : R.color.dark_gray)); // If it is the hint text (position == 0) set the textcolor to be a lighter color

        return convertView;
    }
}

drop_down_row_light_gray:

<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/text"
    style="@style/Base.TextAppearance.AppCompat.Medium"
    android:background="@color/light_gray"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:minHeight="48dp"
    android:paddingLeft="8dp"
    android:paddingRight="16dp"
    android:paddingTop="16dp"
    android:paddingBottom="16dp"
    android:ellipsize="end"
    android:textColor="@color/dark_gray"
    android:gravity="center"/>

closed_row_light_gray:

<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/text"
    style="@style/Base.TextAppearance.AppCompat.Medium"
    android:background="@android:color/transparent"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:minHeight="48dp"
    android:paddingLeft="8dp"
    android:paddingRight="16dp"
    android:paddingTop="16dp"
    android:paddingBottom="16dp"
    android:textColor="@color/dark_gray"
    android:gravity="center"/>

Add "setError" to the spinner :

private void setSubmitButtonOnClickListener() {

        submitButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                if (isFormValid()) {
                    ...

                } else {
 

                    if (isAgeEmpty()) {
                        TextView textView = (TextView) ageSpinner.getSelectedView().findViewById(R.id.text); // "text" is the layout id of the TextView that displays the text
                        textView.setError(getString(R.string.age_is_required));
                    }

                    ...
                }
            }
        });
    }

Notes:
1) In my experience, when I used 9 patch as the spinne's background, the spinner's text dissapeared. It does not happen if I use a "normal" drawable or background color.
2) The "arrow thingy" to the right side of a spinner is actually a background (a 9 patch png). That being said, if you change the spinne background the arrow will dissapear.ng>