首先写个ViewHolder:
public class ViewHolder {private View mConvertView;private Activity mActivity;private SparseArray<View> mViewArray; // 包含了View引用的SparseArraypublic ViewHolder(View convertView) {this.mConvertView = convertView;}public ViewHolder(Activity activity) {this.mActivity = activity;}public <T extends View> T get(int viewId) {//通过ViewId得到Viewif (mActivity == null) {// ListAdapter的ViewHolderSparseArray<View> viewHolder = (SparseArray<View>) mConvertView.getTag();if (viewHolder == null) {viewHolder = new SparseArray<View>();mConvertView.setTag(viewHolder);}View childView = viewHolder.get(viewId);if (childView == null) {childView = mConvertView.findViewById(viewId);viewHolder.put(viewId, childView);}return (T) childView;} else { // Activity的ViewHolderif (mViewArray == null) {mViewArray = new SparseArray<View>();}View childView = mViewArray.get(viewId);if (childView == null) {childView = mActivity.findViewById(viewId);mViewArray.put(viewId, childView);}return (T) childView;}}public void setText(int viewId, String text) {// 通过ViewId设置Text((TextView) get(viewId)).setText(text);}public void setText(int viewId, Spanned text) {// 通过ViewId设置Text((TextView) get(viewId)).setText(text);}public void setTextColor(int viewId, int color) {//通过ViewId设置TextColor((TextView) get(viewId)).setTextColor(color);}public void setImageResource(int viewId, int resId) {//通过ViewId设置图片((ImageView) get(viewId)).setImageResource(resId);}public void setImageBitmap(int viewId, Bitmap bm) {// 通过ViewId设置图片((ImageView) get(viewId)).setImageBitmap(bm);}public void setImageDrawable(int viewId, Drawable drawable) {//通过ViewId设置图片((ImageView) get(viewId)).setImageDrawable(drawable);}public void setImageUrl(int id, String url) {//通过ViewId设置网络图片//Rosemary.loadImage(url, (ImageView) get(id));}public void setImageUrl(int id, String url, int resId) {// 通过ViewId设置网络图片//Rosemary.loadImage(url, (ImageView) get(id), resId);}public void setVisibility(int viewId, int visibility) {//通过ViewId设置隐藏和显示get(viewId).setVisibility(visibility);}public void setOnClickListener(int viewId, View.OnClickListener l) {//通过ViewId设置点击监听get(viewId).setOnClickListener(l);}}
然后写个BaseActivity:
public class BaseActivity extends ActionBarActivity {protected ViewHolder mHolder;public <T> T $(int viewID) {return (T) mHolder.get(viewID);}@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);BaseApplication.getInstance().addActivity(this);mHolder = new ViewHolder(this);}}封装个简易Adapter:
public abstract class ListAdapter<T> extends BaseAdapter {protected Context mContext;protected LayoutInflater mInflater;protected List<T> mList; // 数据集protected int mLayoutID; // 布局资源IDprotected ListAdapter() {}public ListAdapter(Context ctx, List<T> list, int layoutID) {mContext = ctx;mInflater = LayoutInflater.from(ctx);mList = list;mLayoutID = layoutID;}@Overridepublic int getCount() {if (mList != null && mList.size() > 0) return mList.size();return 0;}@Overridepublic T getItem(int position) {if (mList != null && mList.size() > 0) return mList.get(position);return null;}@Overridepublic long getItemId(int position) {return position;}@Overridepublic View getView(int position, View convertView, ViewGroup parent) {if (convertView == null) convertView = mInflater.inflate(mLayoutID, null);ViewHolder holder = new ViewHolder(convertView);onBind(position, getItem(position), holder);return convertView;}/*** 绑定数据*/protected abstract void onBind(int position, T item, ViewHolder holder);}使用效果:
public class BlacklistActivity extends VolleyActivity implements IInit, IResponseHandler {private ListView mListView;private BlacklistViewModel mViewModel = new BlacklistViewModel();private ListAdapter<BlacklistViewModel> mAdapter;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_blacklist);init();}@Overridepublic void init() {ActionBarUtil.setup(this, "我的黑名单");mListView = $(R.id.lv_blacklist);fetchData(FIRST);}@Overridepublic void fetchData(int tag) {toggleProgress(true);if (tag == FIRST) {// 请求黑名单列表GetBlackBuyerListParam param = new GetBlackBuyerListParam(mViewModel.getPageIndex(), Data.PAGE_SIZE_LARGE, Data.getUserID());UserApi.getBlackBuyerList(this, param, tag);} else if (tag == SECOND) {// 移出黑名单RemoveBlackBuyerParam param = new RemoveBlackBuyerParam(Data.getUserID(), mViewModel.getList().get(mViewModel.getCurrentPosition()).getModel().getBuyerID());UserApi.removeBlackBuyer(this, param, tag);}}@Overridepublic void updateUI(Object response, int tag) {if (response == null) return;if (tag == FIRST) {mViewModel.inflate(response);// 黑名单列表if (mAdapter == null) {mAdapter = new ListAdapter<BlacklistViewModel>(this, mViewModel.getList(), R.layout.item_blacklist) {@Overrideprotected void onBind(final int position, final BlacklistViewModel item, ViewHolder holder) {holder.setImageUrl(R.id.iv_avatar, item.getModel().getHeadImageUrl(), R.drawable.defaultportrait);holder.setOnClickListener(R.id.iv_avatar, new View.OnClickListener() {@Overridepublic void onClick(View v) {IntentUtil.toPersonInfo(BlacklistActivity.this, item.getModel().getBuyerID());}});holder.setText(R.id.tv_name, item.getModel().getBuyerName());holder.setOnClickListener(R.id.btn_remove, new View.OnClickListener() {@Overridepublic void onClick(View v) {mViewModel.setCurrentPosition(position);new AlertDialog.Builder(BlacklistActivity.this).setMessage(String.format("确定将“%s”从黑名单中移除吗？", item.getModel().getBuyerName())).setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {fetchData(SECOND);}}).setNegativeButton(android.R.string.cancel, null).create().show();}});}};mListView.setAdapter(mAdapter);mListView.setEmptyView(findViewById(R.id.iv_no_data));} else {mAdapter.notifyDataSetChanged();}} else if (tag == SECOND) {if (((Boolean) response)) {ToastUtil.show(this, "移除成功！");mViewModel.getList().remove(mViewModel.getCurrentPosition());mAdapter.notifyDataSetChanged();}}}}总结:
以前要写mListView = (ListView)findViewById(R.id.lv_blacklist);
现在只要写mListView = $(R.id.lv_blacklist);就可以
而且adapter简化成几行代码:
一个人行走，若是寂寞了，寻一座霓虹灯迷离闪烁，
