listView的万能适配器

通用适配器设计模式

最新推荐文章于 2021-05-27 10:35:50 发布

转载最新推荐文章于 2021-05-27 10:35:50 发布 · 268 阅读

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本文介绍了一种基于Android的通用适配器设计模式，该模式通过抽象类AbsBaseAdapter实现了ListView的数据绑定功能。适配器接收泛型数据列表，并支持数据集的更新和插入操作。此外，还提供了一个ViewHolder子类用于视图缓存。

public abstract class AbsBaseAdapter<T> extends BaseAdapter {
    protected LayoutInflater mInflater;
    protected Context mContext;
    protected List<T> mDatas = new ArrayList<>();
    protected int mItemLayoutId;


    public AbsBaseAdapter(Context mContext, int mItemLayoutId) {
        this.mContext = mContext;
        this.mInflater = LayoutInflater.from(mContext);
        this.mItemLayoutId = mItemLayoutId;
    }
    public void setDatas(List<T> datas){
        this.mDatas = datas;
        notifyDataSetChanged();
    }

    public void addItem(T item){
        if (!mDatas.contains(item)) {
            this.mDatas.add(item);
            notifyDataSetChanged();
        }

    }
    @Override
    public int getCount() {
        return mDatas.size();
    }

    @Override
    public Object 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) {
        ViewHoder hoder ;
        if (convertView == null){
            convertView = mInflater.inflate(mItemLayoutId,null);
            hoder = new ViewHoder(convertView);
            convertView.setTag(hoder);
        } else {
            hoder = (ViewHoder) convertView.getTag();
        }
        bindView(hoder,mDatas.get(position));
        getItemPosition(hoder,position);
        return convertView;
    }

    public void getItemPosition(ViewHoder hoder, int position) {

    }

    public abstract void bindView(ViewHoder hoder, T item);
    public class ViewHoder{
        private View mConvertView;
        private SparseArray<View> mViews = new SparseArray<>();
        public ViewHoder(View mConvertView) {
            this.mConvertView = mConvertView;
        }
        public <V extends View> V getView(@IdRes int viewId){
            View view = mViews.get(viewId);
            if (view == null){
                view = mConvertView.findViewById(viewId);
                mViews.put(viewId,view);
            }
            return (V) view;
        }
    }
}