继承BaseAdapter实现自定义Adapter

android开发中会经常用来自定义的Adapter，如下就是一个简单的自定义Adapter实例。

 

import android.app.Activity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

/**
 * 自定义适配器通过ListView显示内容，这个比较重要需要掌握
 * @author Dylan
 */
public class CustomAdapterActivity extends Activity {

	private ListView mListView;

	private CustomAdapter mAdapter;

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);

		mListView = (ListView) findViewById(R.id.listview);
		mAdapter = new CustomAdapter();
		mListView.setAdapter(mAdapter);
		mListView.setOnItemClickListener(new ItemClickListener());
	}

	private final class ItemClickListener implements OnItemClickListener {

		// AdapterView<?> parent, --> ListView View view, ---> item int
		// position,--> item的数据在Adapter中位置 long id---> item在listView中得位置
		@Override
		public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
			String name = (String) mAdapter.getItem(position);
			Toast.makeText(getApplicationContext(), "name =" + name + ",position " + position, Toast.LENGTH_SHORT)
					.show();
		}
	}

	private final class CustomAdapter extends BaseAdapter {

		private String[] names = new String[] { "无线和网络", "通话设置", "声音", "显示", "位置和安全", "应用程序", "账户与同步", "隐私权",
				"SD卡和手机内存", "语言和键盘", "辅助功能", "日期和时间", "关于手机" };

		private int[] images = new int[] { R.drawable.image01, R.drawable.image02, R.drawable.image03,
				R.drawable.image04, R.drawable.image05, R.drawable.image06, R.drawable.image07, R.drawable.image08,
				R.drawable.image09, R.drawable.image10, R.drawable.image11, R.drawable.image12, R.drawable.image13 };

		private LayoutInflater mInflater;

		public CustomAdapter() {
			mInflater = getLayoutInflater();
		}

		// 描述adpter的大小（确定了listView的条目）
		@Override
		public int getCount() {
			return names.length;
		}

		// Adapter对于的position的数据
		@Override
		public Object getItem(int position) {
			return names[position];
		}

		// 得到item 在adapter所对应的位置
		@Override
		public long getItemId(int position) {
			return position;
		}

		// 创建listview的item条目，把数据绑定给item int position, Adapter的下标 View
		// convertView, 缓存的第一屏item的布局文件 ViewGroup parent ListView
		@Override
		public View getView(int position, View convertView, ViewGroup parent) {
			View view = null;
			if (convertView != null) {
				view = convertView;
			} else {
				view = mInflater.inflate(R.layout.item, parent, false);
			}

			ImageView iv_header = (ImageView) view.findViewById(R.id.iv_header);
			TextView tv_name = (TextView) view.findViewById(R.id.tv_name);

			iv_header.setImageResource(images[position]);
			tv_name.setText(names[position]);

			return view;
		}
		/*
		 * @Override
				public View getView(int position, View convertView, ViewGroup parent) {
					ViewCache viewCache = null;
					if (convertView == null) {
						viewCache = new ViewCache();
						convertView = inflater.inflate(R.layout.folder_list_item, null);
						viewCache.tvName = (TextView) convertView.findViewById(R.id.tv_folder_name);
						viewCache.ivPreview = (ImageView) convertView.findViewById(R.id.iv_folder_preview);
						convertView.setTag(viewCache);
					} else {
						viewCache = (ViewCache) convertView.getTag();
					}
					
					FileInfo fileInfo = arrayList.get(position);
					viewCache.tvName.setText(new File(fileInfo.filePath).getName());
					return convertView;
				}
			public static class ViewCache {
					public ImageView ivPreview;
					public TextView tvName;
	   		}
		 */
	}
}