[Android]ListView学习笔记

基本用法流程

• 创建Adapter并且派生自BaseAdapter,实现其必要的接口方法

• 将创建的Adapter分配给ListView对象：mPhoneBookListView.setAdapter(phoneBookAdapter);

• 针对每一个ItemView,创建Layout,并且在Adapter的getView方法中指定。为了优化性能，这里获取的对象要尽量重用如下：

  @Override
  public View getView(int position, View convertView, ViewGroup parent) {
  
      ViewHolder viewHolder;
  
      //Get a view
      if (convertView == null)
      {
          convertView = mlayoutInflater.inflate(R.layout.item_phone_book_friend,null);
          viewHolder = new ViewHolder();
  
          //获取控件
          viewHolder.nameTextView = (TextView) convertView.findViewById(R.id.name_text_view);
          viewHolder.ageTextView = (TextView) convertView.findViewById(R.id.age_text_view);
          viewHolder.avatarimageView = (ImageView) convertView.findViewById(R.id.avatar_image_view);
  
          convertView.setTag(viewHolder);
      }
      else
      {
          viewHolder = (ViewHolder) convertView.getTag();
  
      }
  
      //Binding data
      viewHolder.nameTextView.setText(mUserInfos.get(position).getUserName());
      viewHolder.ageTextView.setText(String.valueOf(mUserInfos.get(position).getAge()));
      viewHolder.avatarimageView.setImageResource(R.drawable.james22);
  
      return convertView;
  }
  
  class ViewHolder
  {
      //获取控件
      TextView nameTextView;
      TextView ageTextView;
      ImageView avatarimageView;
  
  }
  

• 若更新了ListView使用的数据源，则通过Adapter的notifyDataSetChanged()方法来更新

• 其它常用属性和方法