prebuilts/gradle/AdapterTransition/Application/src/main/java/com/example/android/adaptertransition/MeatAdapter.java

/*
 * Copyright 2014 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.example.android.adaptertransition;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;

/**
 * This class provides data as Views. It is designed to support both ListView and GridView by
 * changing a layout resource file to inflate.
 */
public class MeatAdapter extends BaseAdapter implements AbsListView.OnItemClickListener {

    private final LayoutInflater mLayoutInflater;
    private final int mResourceId;

    /**
     * Create a new instance of {@link MeatAdapter}.
     *
     * @param inflater   The layout inflater.
     * @param resourceId The resource ID for the layout to be used. The layout should contain an
     *                   ImageView with ID of "meat_image" and a TextView with ID of "meat_title".
     */
    public MeatAdapter(LayoutInflater inflater, int resourceId) {
        mLayoutInflater = inflater;
        mResourceId = resourceId;
    }

    @Override
    public int getCount() {
        return Meat.MEATS.length;
    }

    @Override
    public Meat getItem(int position) {
        return Meat.MEATS[position];
    }

    @Override
    public long getItemId(int position) {
        return Meat.MEATS[position].resourceId;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        final View view;
        final ViewHolder holder;
        if (null == convertView) {
            view = mLayoutInflater.inflate(mResourceId, parent, false);
            holder = new ViewHolder();
            assert view != null;
            holder.image = (ImageView) view.findViewById(R.id.meat_image);
            holder.title = (TextView) view.findViewById(R.id.meat_title);
            view.setTag(holder);
        } else {
            view = convertView;
            holder = (ViewHolder) view.getTag();
        }
        Meat meat = getItem(position);
        holder.image.setImageResource(meat.resourceId);
        holder.title.setText(meat.title);
        return view;
    }

    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
        ViewHolder holder = (ViewHolder) view.getTag();
        Context context = view.getContext();
        if (null != holder && null != holder.title && null != context) {
            Toast.makeText(context, context.getString(R.string.item_clicked,
                    holder.title.getText()), Toast.LENGTH_SHORT).show();
        }
    }

    private static class ViewHolder {
        public ImageView image;
        public TextView title;
    }

}