Android Adapter的简单封装

HolderAdapter背景

Android的AdapterView用的比较多，ListView，GridView，Spinner等，原生的BaseAdapter对ViewHolder没有支持，每次都要，定义内部类，inflater根布局，对item内部view设置clicklistener并转发到adapter的调用者等。写的次数多了感觉很繁琐，于是写了个简单的封装，简化Adapter的编写，仓库连接http://git.oschina.net/phodev/SimpleAdapter.

主要文件介绍

1，CommonAdapter.java从BaseAdapter继承，添加了常用的函数，通过泛型约定了List数据源，代替子类实现getCount功能,添加bindClick实现Adapter的OnItemClickListener。

2，BaseViewHolder.java和HolderAdapter结合，实现类似Activity的view初始化方方式onCreate->setContentView->findViewById。

3，HolderAdapter.java从CommonAdapter继承，主要用来驱动BaseViewHolder工作。

使用方法

1,Adapter定义

public class SampleHolderAdapter extends HolderAdapter<Object> {    //定义Item内部的点击事件，如果不需要可以不定义    public static final int CLICK_ACTION_ADD = 1;    public static final int CLICK_ACTION_UPDATE = 2;    public static final int CLICK_ACTION_DELETE = 3;    //构造函数配置数据源（可选，或者之后通过setData更新）    public SampleHolderAdapter(List<Object> data) {        super(data);    }    @Override    public BaseViewHolder<?> createViewHolder(int position) {        //创建期望的 ViewHolder        return new ViewHolder();    }    class ViewHolder extends BaseViewHolder<Object> {        Button btn1, btn2, btn3;        @Override        protected void onCreate(Context context, ViewGroup parent) {            //ViewHolder创建后onCreate会被执行1次            setContentView(R.layout.item_test);//setContent支持View或者layout id            btn1 = (Button) findViewById(R.id.btn1);//findViewById            btn2 = (Button) findViewById(R.id.btn2);            btn3 = (Button) findViewById(R.id.btn3);        }        @Override        protected void onDataChanged(int position, Object data) {            //adapter getView的时候onDataChanged会被执行一次            btn1.setText("add " + position);            btn2.setText("update " + position);            btn3.setText("delete " + position);            //            bindClick(btn1, position, CLICK_ACTION_ADD);//绑定ItemClick，每次都需bind            bindClick(btn2, position, CLICK_ACTION_UPDATE);            bindClick(btn3, position, CLICK_ACTION_DELETE);        }    }}

2,Adapter使用

 //数据源        private final ArrayList<Object> mData = new ArrayList<>();    //创建Adapter并绑定数据源    private final SampleHolderAdapter mAdapter = new SampleHolderAdapter(mData);    @Override    protected void onCreate(@Nullable Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        mListView = (ListView) findViewById(R.id.listview);        //绑定Adapter        mListView.setAdapter(mAdapter);        //设置click listener（由于CommonAdapter支持，并通过bindClick声明）        mAdapter.setOnItemClickListener(onItemClickListener);    }    //ClickListener实现    private OnItemClickListener onItemClickListener = new OnItemClickListener() {        @Override        public void onItemClick(CommonAdapter<?> adapter, View v, int position, int action) {            switch (action) {//action就是我们SampleHolderAdapte中定义并且bindClick的value                case SampleHolderAdapter.CLICK_ACTION_ADD:                    toast(getContext(), position + " add click");                    break;                case SampleHolderAdapter.CLICK_ACTION_UPDATE:                    toast(getContext(),position + " update click");                    break;                case SampleHolderAdapter.CLICK_ACTION_DELETE:                    toast(getContext(), position + " delete click");                    break;            }        }    };

到此定义和使用的代码完毕。