Android容易开发之 通用Adapter ViewHolder

我们平常使用Adapter的方式

public class BusbaseSearchApadter extends SimpleBaseApadter {	private List<Busbase> busbases = new ArrayList<Busbase>();	public Context context;	public void setList(List<Busbase> busbases) {		this.busbases = busbases;	}		public BusbaseSearchApadter(Context context) {		super(context);		this.context = context;	}	@Override	public int getCount() {		return busbases.size();	}	@Override	public Object getItem(int position) {		return busbases.get(position);	}	@Override	public long getItemId(int position) {		return position;	}	@Override	public View getView(int position, View convertView, ViewGroup parent) {		Busbase busbase = busbases.get(position);		ViewHolder holder = null;		if(convertView == null){			holder = new ViewHolder();			convertView = LayoutInflater.from(context).inflate(R.layout.hx_item_search_bus, parent, false);			holder.hx_item_bus_search_image = (ImageView)convertView.findViewById(R.id.hx_item_bus_search_image);			holder.hx_item_bus_search_name = (TextView)convertView.findViewById(R.id.hx_item_bus_search_name);			holder.hx_item_bus_search_mobile = (TextView)convertView.findViewById(R.id.hx_item_bus_search_mobile);			convertView.setTag(holder);		}else{			holder = (ViewHolder)convertView .getTag();		}		bitmapUtils.display(holder.hx_item_bus_search_image, busbase.getShopLogo());		holder.hx_item_bus_search_name.setText(busbase.name);		holder.hx_item_bus_search_mobile.setText(busbase.mobile);		return convertView;	}	class ViewHolder{		ImageView hx_item_bus_search_image;		TextView hx_item_bus_search_name;		TextView hx_item_bus_search_mobile;	}

可以看出其中  有用的代码只有只有getView  和ViewHolder  但是其他的代码又不得不写，太痛苦 了不得不重复的写无数adapter 和ViewHoder.

我们可以写一个通用的ViewHolder

public class ViewHolder {	private final SparseArray<View> mViews;      private int mPosition;      private View mConvertView;      protected BitmapUtils bitmapUtils;      private ViewHolder(Context context, ViewGroup parent, int layoutId,              int position)      {      	bitmapUtils = new BitmapUtils(context);		bitmapUtils.configDefaultLoadingImage(R.drawable.hx_loodding);		bitmapUtils.configDefaultLoadFailedImage(R.drawable.hx_loodding);		bitmapUtils.configDefaultBitmapConfig(Bitmap.Config.RGB_565);        this.mPosition = position;          this.mViews = new SparseArray<View>();          mConvertView = LayoutInflater.from(context).inflate(layoutId, parent,                  false);          // setTag          mConvertView.setTag(this);      }        /**      * 拿到一个ViewHolder对象      *       * @param context      * @param convertView      * @param parent      * @param layoutId      * @param position      * @return      */      public static ViewHolder get(Context context, View convertView,              ViewGroup parent, int layoutId, int position)      {          if (convertView == null)          {              return new ViewHolder(context, parent, layoutId, position);          }          return (ViewHolder) convertView.getTag();      }        public View getConvertView()      {          return mConvertView;      }        /**      * 通过控件的Id获取对于的控件，如果没有则加入views      *       * @param viewId      * @return      */      public <T extends View> T getView(int viewId)      {          View view = mViews.get(viewId);          if (view == null)          {              view = mConvertView.findViewById(viewId);              mViews.put(viewId, view);          }          return (T) view;      }        /**      * 为TextView设置字符串      *       * @param viewId      * @param text      * @return      */      public ViewHolder setText(int viewId, String text)      {          TextView view = getView(viewId);          view.setText(text);          return this;      }        /**      * 为ImageView设置图片      *       * @param viewId      * @param drawableId      * @return      */      public ViewHolder setImageResource(int viewId, int drawableId)      {          ImageView view = getView(viewId);          view.setImageResource(drawableId);            return this;      }        /**      * 为ImageView设置图片      *       * @param viewId      * @param drawableId      * @return      */      public ViewHolder setImageBitmap(int viewId, Bitmap bm)      {          ImageView view = getView(viewId);          view.setImageBitmap(bm);          return this;      }        /**      * 为ImageView设置图片      *       * @param viewId      * @param drawableId      * @return      */      public ViewHolder setImageByUrl(int viewId, String url)      {      	bitmapUtils.display((ImageView) getView(viewId), url);        return this;      }        public int getPosition()      {          return mPosition;      }

现在Adapter这样写

public abstract class AbstuctBaseApadter<T> extends SimpleBaseApadter {	protected LayoutInflater mInflater;  	protected Context mContext;  	protected List<T> mDatas;  	protected int mItemLayoutId;  	public AbstuctBaseApadter(Context context) {		super(context);	}      public AbstuctBaseApadter(Context context, List<T> mDatas, int itemLayoutId)      {      	this(context);        this.mContext = context;          this.mInflater = LayoutInflater.from(mContext);          this.mDatas = mDatas;          this.mItemLayoutId = itemLayoutId;      }          public void setList(List<T> mDatas){    	 this.mDatas = mDatas;      }      @Override      public int getCount()      {          return mDatas.size();      }        @Override      public T getItem(int position)      {          return mDatas.get(position);      }        @Override      public long getItemId(int position)      {          return position;      }        @Override      public View getView(int position, View convertView, ViewGroup parent)      {          final ViewHolder viewHolder = getViewHolder(position, convertView,                  parent);          convert(viewHolder, getItem(position));          return viewHolder.getConvertView();        }        public abstract void convert(ViewHolder helper, T item);        private ViewHolder getViewHolder(int position, View convertView,              ViewGroup parent)      {          return ViewHolder.get(mContext, convertView, parent, mItemLayoutId,                  position);      }

现在我们只需要重写 convert方法  看activity里面怎么使用

		AbstuctBaseApadter abstuctBaseApadter = new AbstuctBaseApadter<Map<String,Object>>(activity,list_map,R.layout.hx_money_item) {			public void convert(ViewHolder helper, Map<String, Object> item) {				helper.setText(R.id.id_item_1, item.get("time").toString());				helper.setText(R.id.id_item_3, item.get("sourcename").toString());			}		};

哈哈  打工改成