MovieAdapter.java :  » App » android-in-practice » com » manning » aip » mymovies » Android Open Source

package com.manning.aip.mymovies;

import java.util.HashMap;

import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.CheckedTextView;

public class MovieAdapter extends ArrayAdapter<String> {

   private HashMap<Integer, Boolean> movieCollection =
            new HashMap<Integer, Boolean>();

   public MovieAdapter(Context context) {
      super(context, R.layout.movie_item, android.R.id.text1, context
               .getResources().getStringArray(R.array.movies));
   }

   public void toggleMovie(int position) {
      if (!isInCollection(position)) {
         movieCollection.put(position, true);
      } else {
         movieCollection.put(position, false);
      }
   }

   public boolean isInCollection(int position) {
      return movieCollection.get(position) == Boolean.TRUE;
   }

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

      View listItem = super.getView(position, convertView, parent);

      CheckedTextView checkMark = null;
      ViewHolder holder = (ViewHolder) listItem.getTag();
      if (holder != null) {
         checkMark = holder.checkMark;
      } else {
         checkMark = (CheckedTextView) listItem.findViewById(android.R.id.text1);
         holder = new ViewHolder(checkMark);
         listItem.setTag(holder);
      }
      
      checkMark.setChecked(isInCollection(position));

      return listItem;
   }

   private class ViewHolder {
      protected final CheckedTextView checkMark;

      public ViewHolder(CheckedTextView checkMark) {
         this.checkMark = checkMark;
      }
   }
}