NavigationDrawerAdapter.java

public class NavigationDrawerAdapter extends ArrayAdapter<Object> {

    private static final int HEADER_ROW = 0;
    private static final int CONTACT_DETAIL_ROW = 1;
    private static final int PREFERENCE_ROW = 2;
    private static final int LINK = 3;
    private static final int[] ROW_TYPES = {HEADER_ROW, CONTACT_DETAIL_ROW, PREFERENCE_ROW, LINK};

    private Activity mHost;
    private List<Object> mDrawerItemList = new ArrayList<Object>();

    public NavigationDrawerAdapter(Activity activity, int resource, List<Object> objectList) {
        super(activity, resource, objectList);
        this.mHost = activity;
        this.mDrawerItemList = objectList;
    }

    @Override
    public int getItemViewType(int position) {
        if (mDrawerItemList.get(position) instanceof NavDrawerLinkItem) {
            return LINK;
        } else if (mDrawerItemList.get(position) instanceof NavDrawerContactItem) {
            return CONTACT_DETAIL_ROW;
        } else if (mDrawerItemList.get(position) instanceof NavDrawerPreferenceItem) {
            return PREFERENCE_ROW;
        } else {
            return HEADER_ROW;
        }
    }

    @Override
    public int getViewTypeCount() {
        return ROW_TYPES.length;
    }

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

        LinkItemHolder linkItemHolder;
        ContactItemHolder contactItemHolder;
        PreferenceItemHolder preferenceItemHolder;
        HeaderItemHolder headerItemHolder;

        LayoutInflater inflater = mHost.getLayoutInflater();

        switch (getItemViewType(position)) {

            case LINK:

                // null our other view holders
                contactItemHolder = null;
                preferenceItemHolder = null;
                headerItemHolder = null;

                if (convertView == null) {
                    convertView = inflater.inflate(R.layout.navigation_drawer_link_item, parent, false);
                    linkItemHolder = new LinkItemHolder(convertView);
                    convertView.setTag(linkItemHolder);
                } else {
                    linkItemHolder = (LinkItemHolder) convertView.getTag();
                }
                NavDrawerLinkItem linkItem = (NavDrawerLinkItem) this.mDrawerItemList.get(position);
                linkItemHolder.linkName.setText(linkItem.getItemName());
                break;

            case CONTACT_DETAIL_ROW:

                // null our other view holders
                linkItemHolder = null;
                preferenceItemHolder = null;
                headerItemHolder = null;

                if (convertView == null) {
                    convertView = inflater.inflate(R.layout.navigation_drawer_contact_item, parent, false);
                    contactItemHolder = new ContactItemHolder(convertView);
                    convertView.setTag(contactItemHolder);
                } else {
                    contactItemHolder = (ContactItemHolder) convertView.getTag();
                }
                NavDrawerContactItem contactItem = (NavDrawerContactItem) this.mDrawerItemList.get(position);
                contactItemHolder.someTextView.setText(contactItem.getItemName());
                break;

            case PREFERENCE_ROW:

                // null our other view holders
                linkItemHolder = null;
                contactItemHolder = null;
                headerItemHolder = null;

                if (convertView == null) {
                    convertView = inflater.inflate(R.layout.navigation_drawer_preference_item, parent, false);
                    preferenceItemHolder = new PreferenceItemHolder(convertView);
                    convertView.setTag(preferenceItemHolder);
                } else {
                    preferenceItemHolder = (PreferenceItemHolder) convertView.getTag();
                }
                NavDrawerPreferenceItem preferenceItem = (NavDrawerPreferenceItem) this.mDrawerItemList.get(position);
                preferenceItemHolder.someTextView.setText(preferenceItem.getItemName());
                break;

            case HEADER_ROW:

                // null our other view holders
                linkItemHolder = null;
                contactItemHolder = null;
                preferenceItemHolder = null;

                if (convertView == null) {
                    convertView = inflater.inflate(R.layout.navigation_drawer_header_item, parent, false);
                    headerItemHolder = new HeaderItemHolder(convertView);
                    convertView.setTag(headerItemHolder);
                } else {
                    headerItemHolder = (HeaderItemHolder) convertView.getTag();
                }
                NavDrawerHeaderItem headerItem = (NavDrawerHeaderItem) this.mDrawerItemList.get(position);
                headerItemHolder.someTextView.setText(headerItem.getItemName());
                break;
        }
        return convertView;
    }

    private static class LinkItemHolder {
        TextView linkName;

        LinkItemHolder(View v) {
            this.linkName = (TextView) v.findViewById(R.id.navigation_drawer_link_item);
        }
    }

    private static class PreferenceItemHolder {
        TextView someTextView;

        PreferenceItemHolder(View v) {
            this.someTextView = (TextView) v.findViewById(R.id.navigation_drawer_preference_item);
        }
    }

    private static class HeaderItemHolder {
        TextView someTextView;

        HeaderItemHolder(View v) {
            this.someTextView = (TextView) v.findViewById(R.id.navigation_drawer_header_item);
        }
    }

    private static class ContactItemHolder {
        TextView someTextView;

        ContactItemHolder(View v) {
            this.someTextView = (TextView) v.findViewById(R.id.navigation_drawer_contact_item);
        }
    }
}