ListView通用Adapter

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双11人人都在遛京东,喂天猫,逛淘宝,而作为程序员我们只能撸代码。。。没有最好,只有更好,两行代码展示一个聊天列表，打造一个通用适配器是件一劳永逸的事
1. ViewHolder
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/**
 * Created by zhangfeng on 2016/11/11.
 * 通用ViewHolder
 */
public class ViewHolder {
    private Context mContext;
    /**
     * 存放的view的map,这里我们使用SparseArray(key是固定的为int类型)
     */
    private SparseArray<View> mViews;
    /**
     * 位置
     */
    private int mPosition;
    /**
     * item view
     */
    private View mConvertView;
    public ViewHolder(Context context, ViewGroup parent, int layoutId, int position) {
        this.mContext = context;
        this.mPosition = position;
        this.mViews = new SparseArray<>();
        mConvertView = LayoutInflater.from(context).inflate(layoutId, parent, false);
        mConvertView.setTag(this);
    }
    public static ViewHolder get(Context context, View convertView, ViewGroup parent, int layoutId, int position) {
        if (convertView == null) {
            return new ViewHolder(context, parent, layoutId, position);
        } else {
            ViewHolder holder = (ViewHolder) convertView.getTag();
            holder.mPosition = position;
            return holder;
        }
    }
    /**
     * 通过 viewId获取 view
     *
     * @param viewId
     * @param <T>
     * @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;
    }
    public View getmConvertView() {
        return mConvertView;
    }
    /**
     * TextView赋值
     *
     * @param viewId
     * @param text
     * @return
     */
    public ViewHolder setText(int viewId, String text) {
        TextView tv = getView(viewId);
        tv.setText(text);
        return this;
    }
    /**
     * Glide 加载图片
     *
     * @param viewId
     * @param errorDrawable
     * @param placeholderDrable
     * @param str
     * @return
     */
    public ViewHolder setImage(int viewId, Drawable errorDrawable, Drawable placeholderDrable, String str) {
        ImageView iv = getView(viewId);
        Glide.with(mContext).load(str).error(errorDrawable).placeholder(placeholderDrable).into(iv);
        return this;
    }
}
2. CommonAdapter
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/**
 * Created by zhangfeng on 2016/11/11.
 * 通用适配器
 */
public abstract class CommonAdapter<T> extends BaseAdapter {
    protected Context mContext;
    protected LayoutInflater layoutInflater;
    protected List<T> mDatas;
    public CommonAdapter(Context context, List<T> datas) {
        this.mContext = context;
        layoutInflater = LayoutInflater.from(context);
        this.mDatas = datas;
    }
    @Override
    public int getCount() {
        return mDatas == null ? 0 : 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) {
        ViewHolder holder = ViewHolder.get(mContext, convertView, parent, R.layout.item_list, position);
        convert(holder, getItem(position));
        return holder.getmConvertView();
    }
    public abstract void convert(ViewHolder holder, T t);
}
3. MsgAdapter继承CommonAdapter
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/**
 * Created by zhangfeng on 2016/11/11.
 */
public class MsgAdapter extends CommonAdapter<MsgBean> {
    public MsgAdapter(Context context, List<MsgBean> datas) {
        super(context, datas);
    }
    @Override
    public void convert(ViewHolder holder, MsgBean msgBean) {
        ((ImageView) holder.getView(R.id.iv_user_head)).setImageDrawable(mContext.getResources().getDrawable(msgBean.getUserHea()));
        holder.setText(R.id.tv_nick_name, msgBean.getNickName())
                .setText(R.id.tv_msg_tip, msgBean.getMsgTip())
                .setText(R.id.tv_update_time, msgBean.getUpdateTime());
    }
4. 实体
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/**
 * Created by zhangfeng on 2016/11/11.
 */
public class MsgBean {
    private int userHea;
    private String nickName;
    private String msgTip;
    private String updateTime;
    public MsgBean(int userHea, String nickName, String msgTip, String updateTime) {
        this.userHea = userHea;
        this.nickName = nickName;
        this.msgTip = msgTip;
        this.updateTime = updateTime;
    }
.........省略 getter setter
5. 测试
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public class MainActivity extends AppCompatActivity {
    private MainActivity self;
    private ListView mListView;
    private List<MsgBean> mDatas;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initView();
        initData();
    }
    private void initView() {
        self=this;
        mListView = (ListView) findViewById(R.id.id_list);
    }
    private void initData() {
        mDatas=new ArrayList<>();
        MsgBean msgBean1 = new MsgBean(R.mipmap.man1, "隔壁老王", "晚上一起喝酒", "17:16");
        MsgBean msgBean2 = new MsgBean(R.mipmap.girl, "小花妹子", "下班请你吃饭", "17:24");
        MsgBean msgBean3 = new MsgBean(R.mipmap.boy3, "好基友", "好吧,那改天吧", "17:33");
        MsgBean msgBean4 = new MsgBean(R.mipmap.girl5, "校花", "我已经开好房间了", "17:47");
        MsgBean msgBean5 = new MsgBean(R.mipmap.girl1, "老婆大人", "下班了就赶快回来", "18:02");
        mDatas.add(msgBean1);
        mDatas.add(msgBean2);
        mDatas.add(msgBean3);
        mDatas.add(msgBean4);
        mDatas.add(msgBean5);
        mListView.setAdapter(new MsgAdapter(self,mDatas));
    }

通用适配器