Android开发-适配器优化

我会带着你远行 2022-05-18 02:46 156阅读 0赞

在android开发中，常用ListView、GridView来显示多项数据。对适配器加以优化能够让每次适配数据变得更加简单，性能更加高效。下面是适配器优化后的代码：

>     public abstract class CommonAdapter<<span style="color:#20999d;">T> extends BaseAdapter{
> 
>     Context context;
>     int resId;
>     List<</font>T> datas;
>     LayoutInflater layoutInflater;
>     
>     public CommonAdapter(List<</font>T> datas,Context context,int resId)
>     {
> 
>     this.datas=datas;
>     this.context=context;
>     this.resId=resId;
>     layoutInflater=LayoutInflater.from(context);
>     }
>     
>     @Override
>     public int getCount() {
> 
>     return datas.size();
>     }
>     
>     @Override
>     public Object getItem(int i) {
>     return datas.get(i);
>     }
>     
>     @Override
>     public long getItemId(int i) {
>     return i;
>     }
>     
>     @Override
>     public View getView(int i, View view, ViewGroup viewGroup) {
>     
>     T data = datas.get(i);
>     
>     
>     if(view==null)
>     {
> 
>     view = layoutInflater.inflate(resId,null);
>     
>     ViewHolder holder = new ViewHolder(view);
>     view.setTag(holder);
>     
>     }
>     
>     ViewHolder holder = (ViewHolder) view.getTag();
> 
>     setData(data,holder,context);
>     
>     return view;
>     }
>     
>     
>     public abstract void setData(T data, ViewHolder holder,Context context);
>     
>     }
> 
>     //创建一个类来保存控件
> 
>      
> 
>     public class ViewHolder {
>     
>     Map allview = new HashMap<>();
>     View item;
>     public ViewHolder(View item) {
>     
>     this.item=item;
>     }
>     
>     public View getView(int redid)
>     {
>     
>     View v = allview.get(redid);
>     if(v==null)
>     {
>     
>     View view = item.findViewById(redid);
>     allview.put(redid,view);
>     return view;
>     }
>     else{
>     return v;
>     }
>     }
>     }
> 
>     //使用适配器:
> 
>     public class ArticleAdapter extends CommonAdapter{
>     public ArticleAdapter(List datas, Context context, int resId) {
>     super(datas, context, resId);
>     }
>     
>     @Override
>     public void setData(Article data, ViewHolder holder,Context context) {
>     ImageView logo = (ImageView)holder.getView(R.id.alogo);
>     TextView title = (TextView)holder.getView(R.id.aname);
> 
>     logo.setImageBitmap(data.logo);
>     title.setText(data.title);
>     }
>     }

使用适配器时,传入数据,上下文,模板id即可