[android开发]封装BaseAdapter, 简便代码

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参数说明: 构造函数的list参数是你的ListView的数据, 而viewHolder是你的ViewHolder类.

思路说明: getView方法中已经实现了view的初始化, 并且把viewholder中的字段进行注入, 然后通过view.setTag()设置给该view.

使用说明: 在抽象方法initView中通过view.getTag()拿到viewholder, 然后对里面的控件进行操作即可~

当然, 这样封装会有一些局限性, 毕竟封装了就会失去一些灵活性嘛.

public abstract class BeanAdapter extends BaseAdapter {List mList;Context context;int layoutId;Class wiewHolder;public BeanAdapter(Context context, int layoutId, List list, Class wiewHolder) {this.mList = list;this.context = context;this.layoutId = layoutId;this.wiewHolder = wiewHolder;}@Overridepublic int getCount() {return mList.size();}@Overridepublic Object getItem(int position) {return mList.get(position);}@Overridepublic long getItemId(int position) {return position;}@Overridepublic View getView(int position, View view, ViewGroup parent) {if (view == null) {view = LayoutInflater.from(context).inflate(layoutId, parent, false);try {Constructor constructor = wiewHolder.getDeclaredConstructor();constructor.setAccessible(true);Object obj = constructor.newInstance();ViewUtil.setViewHolder(view, obj);} catch (Exception e) {}}initView(position, getItem(position), view, view.getTag());return view;}public abstract void initView(int position, Object item, View view, Object viewHolder);}

附上setViewHolder方法, 跟另一篇文章的属性注入findView方法类似:

//自动注入根据viewHolder中成员变量的名称注入view，并通过setTag()设置给view

public static void setViewHolder(View view, Object viewHolder) {try {ViewGroup viewGroup = (ViewGroup) view;Class clazz = viewHolder.getClass();Field[] fields = clazz.getDeclaredFields();String fieldName = null;// 遍历所有字段for (Field field : fields) {fieldName = field.getName();// 包含_try {Field idField = R.id.class.getField(fieldName);int id = (Integer) idField.get(null);view = viewGroup.findViewById(id);field.setAccessible(true);// 设置给viewHolderfield.set(viewHolder, view);} catch (Exception e) {}}// viewHolder设置给viewGroupviewGroup.setTag(viewHolder);} catch (Exception e) {}}

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