ListAdapter.java :  » File » mandfilebrowser » com » marcnuri » android » widget » Android Open Source

package com.marcnuri.android.widget;

import java.util.ArrayList;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
/**
 * @author Marc Nuri San Flix
 * 
 */
public abstract class ListAdapter<T, V extends ViewHolder<T>> extends
    BaseAdapter {
  protected Context context;
  private ArrayList<T> listItems = new ArrayList<T>();
  private LayoutInflater layoutInflater;
  private int mViewId;

  public ListAdapter(Context context, int viewid, ArrayList<T> listItems) {
    layoutInflater = LayoutInflater.from(context);
    mViewId = viewid;
    this.listItems = listItems;
    this.context = context;
  }

  public int getCount() {
    return listItems.size();
  }

  public T getItem(int position) {
    return listItems.get(position);
  }

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

  @SuppressWarnings("unchecked")
  public View getView(int position, View view, ViewGroup parent) {
    // A ViewHolder keeps references to children views to avoid uneccessary
    // calls
    // to findViewById() on each row.
    V holder;

    // When view is not null, we can reuse it directly, there is no need
    // to reinflate it. We only inflate a new View when the view supplied
    // by ListView is null.
    if (view == null) {

      view = layoutInflater.inflate(mViewId, null);
      // call the user's implementation
      holder = createHolder(view);
      // we set the holder as tag
      view.setTag(holder);

    } else {
      // get holder back...much faster than inflate
      holder = (V) view.getTag();
    }

    // we must update the object's reference
    holder.data = getItem(position);
    // call the user's implementation
    bindHolder(holder);

    return view;
  }

  /**
   * Creates your custom holder, that carries reference for e.g. ImageView
   * and/or TextView. If necessary connect your clickable View object with the
   * PrivateOnClickListener, or PrivateOnLongClickListener
   * 
   * @param vThe
   *            view for the new holder object
   */
  protected abstract V createHolder(View v);

  /**
   * Binds the data from user's object to the holder
   * 
   * @param h
   *            The holder that shall represent the data object.
   */
  protected abstract void bindHolder(V h);
}