basic spinner example

    spinCountry.setOnItemSelectedListener(new OnItemSelectedListener() {
        @Override
         public void onItemSelected(AdapterView<?> parentView,
                 View selectedItemView, int position, long id) {
             try {

                  String select_item =parentView.getItemAtPosition(position).toString();
                 } 
           catch (Exception e) {

            }
        }
        @Override
        public void onNothingSelected(AdapterView<?> parentView) {

        }

    });

b.setOnClickListener(new OnClickListener()
    {

        public void onClick(View arg0)
        {
            String spin=s.getSelectedItem().toString();
                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
            tv.setText(spin);
        }
    });

You dont need shared preference to load values in spinner. You just need to declare array in string.xml file and load that.I am giving you my code.Just use it.:-

STEP-1:-

Declare array for spinner in your string.xml(res->values->strings.xml):--

<string-array name="country_array">
    <item>Greece</item>
    <item>United Kingdom</item>
    <item>Italy</item>
    <item>France</item>
    <item>Germany</item>
    <item>Turkey</item>
    <item>Poland</item>
    <item>India</item>
</string-array>

STEP-2:-

Declare Spinner widget in your layout xml file

<Spinner
     android:id="@+id/spinCountry"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:layout_marginTop="5dp"
     android:paddingLeft="8dp"
     android:popupBackground="@android:color/white"
     android:scrollbars="none"
     android:spinnerMode="dropdown" />

STEP-3:-

Declare Spinner in your Activity

Spinner spinCountry;
spinCountry= (Spinner) findViewById(R.id.spinCountry);//fetch the spinner from layout file
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
            android.R.layout.simple_spinner_item, getResources()
                    .getStringArray(R.array.country_array));//setting the country_array to spinner
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    spinCountry.setAdapter(adapter);
//if you want to set any action you can do in this listener
spinCountry.setOnItemSelectedListener(new OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> arg0, View arg1,
                int position, long id) {
        }

        @Override
        public void onNothingSelected(AdapterView<?> arg0) {
        }
    });