Start activity from adapter don't work with SwipeListView library

I'm using SwipeListView library and I'm getting error when trying to start an activity in my adapter.

public class ProductAdapter extends ArrayAdapter<Product> {



private Context context;



public ProductAdapter(Context context, int textViewResourceId, List<Product> objects) {

    super(context, textViewResourceId, objects);

}



@Override

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



    ViewHolder viewHolder;



    final Product product = getItem(position);



    if (convertView == null) {

        viewHolder = new ViewHolder();



        convertView = LayoutInflater.from(getContext()).inflate(R.layout.cproduct_list_item, null);



        viewHolder.nom = (TextView) convertView.findViewById(R.id.name);

        viewHolder.commerce = (TextView) convertView.findViewById(R.id.commerce);

        viewHolder.prix = (TextView) convertView.findViewById(R.id.price);

        viewHolder.bAction1 = (Button) convertView.findViewById(R.id.example_row_b_action_1);

        viewHolder.bAction2 = (Button) convertView.findViewById(R.id.example_row_b_action_2);

        viewHolder.bAction3 = (Button) convertView.findViewById(R.id.example_row_b_action_3);



        convertView.setTag(viewHolder);



    } 

    else {

        viewHolder = (ViewHolder) convertView.getTag();

    }



    viewHolder.nom.setText(product.getName());

    viewHolder.commerce.setText(product.getCommerce());

    viewHolder.prix.setText(String.format("%s F", product.getPrice()));



    viewHolder.bAction1.setOnClickListener(new OnClickListener() {

        @Override

        public void onClick(View v) {

            Intent intent = new Intent(context, MainActivity.class);

            context.startActivity(intent);

        }

    });



    return convertView;

}



private class ViewHolder {

    TextView nom;

    TextView commerce;

    TextView prix;

    Button bAction1;

    Button bAction2;

    Button bAction3;

}

}

When I click on the button I get this error: "The application has stopped unexpectedly". But when I use a Toast, it works fine. I think there is something inconsistent with starting activity.

Logcat:

04-16 18:42:29.531: E/AndroidRuntime(29813): FATAL EXCEPTION: main
04-16 18:42:29.531: E/AndroidRuntime(29813): java.lang.NullPointerException
04-16 18:42:29.531: E/AndroidRuntime(29813): at com.tomsyweb.suna.ProductAdapter$2.onClick(ProductAdapter.java:71)
04-16 18:42:29.531: E/AndroidRuntime(29813): at android.view.View.performClick(View.java:2485)
04-16 18:42:29.531: E/AndroidRuntime(29813): at android.view.View$PerformClick.run(View.java:9080)
04-16 18:42:29.531: E/AndroidRuntime(29813): at android.os.Handler.handleCallback(Handler.java:587)
04-16 18:42:29.531: E/AndroidRuntime(29813): at android.os.Handler.dispatchMessage(Handler.java:92)
04-16 18:42:29.531: E/AndroidRuntime(29813): at android.os.Looper.loop(Looper.java:130)
04-16 18:42:29.531: E/AndroidRuntime(29813): at android.app.ActivityThread.main(ActivityThread.java:3687)
04-16 18:42:29.531: E/AndroidRuntime(29813): at java.lang.reflect.Method.invokeNative(Native Method)
04-16 18:42:29.531: E/AndroidRuntime(29813): at java.lang.reflect.Method.invoke(Method.java:507)
04-16 18:42:29.531: E/AndroidRuntime(29813): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
04-16 18:42:29.531: E/AndroidRuntime(29813): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:625)
04-16 18:42:29.531: E/AndroidRuntime(29813): at dalvik.system.NativeStart.main(Native Method)