android：使用BaseExpandableListAdapter實現可摺疊的列表

使用BaseExpandableListAdapter 可以實現所謂的可摺疊的列表，例如QQ裡好友的分組的功能。

BaseExpandableListAdapter與BaseAdapter的基本原理是一樣的，只不過在傳入list的時候，要傳入兩組，一組是groupArray ，一組時childArray，前者用於組名（類似QQ的好友、同學、朋友），後者的每個元素都是一組子資料（類似QQ同學中的張三，李四的集合），實現adapter

    public class ExpandableAdapter extends BaseExpandableListAdapter{         private LinkedList<TeacherSumGroupsModel> groupArray;         private List<LinkedList<TeacherSumGroupDetailModel>> childArray;         private Context context;         private LayoutInflater inflater;                          public ExpandableAdapter(Context context,LinkedList<TeacherSumGroupsModel> courseGroupList,                    List<LinkedList<TeacherSumGroupDetailModel>> childArray){             inflater = ((Activity) context).getLayoutInflater();                          this.groupArray = courseGroupList;             this.childArray = childArray;         }                                public int getGroupCount() {            // TODO Auto-generated method stub            return groupArray.size();        }        public int getChildrenCount(int groupPosition) {            // TODO Auto-generated method stub            return childArray.get(groupPosition).size();        }        public Object getGroup(int groupPosition) {            // TODO Auto-generated method stub            return groupArray.get(groupPosition);        }        public Object getChild(int groupPosition, int childPosition) {            // TODO Auto-generated method stub            return childArray.get(groupPosition).get(childPosition);        }        public long getGroupId(int groupPosition) {            // TODO Auto-generated method stub            return groupPosition;        }        public long getChildId(int groupPosition, int childPosition) {            // TODO Auto-generated method stub            return childPosition;        }        public boolean hasStableIds() {            // TODO Auto-generated method stub            return false;        }        public View getGroupView(int groupPosition, boolean isExpanded,                View convertView, ViewGroup parent) {            // TODO Auto-generated method stub                        TextView title;            if(convertView == null){                convertView = inflater.inflate(R.layout.simple_listview_item, parent, false);            }            title = (TextView) convertView.findViewById(R.id.simple_listview_textview);            String t = "     "+groupArray.get(groupPosition).getname();            title.setText(t);            return convertView;        }        public View getChildView(int groupPosition, int childPosition,                boolean isLastChild, View convertView, ViewGroup parent) {            // TODO Auto-generated method stub            TextView title;            if(convertView == null){                convertView = inflater.inflate(R.layout.simple_listview_item, parent, false);            }            title = (TextView) convertView.findViewById(R.id.simple_listview_textview);                        String account = childArray.get(groupPosition).get(childPosition).getAccount();            String name = childArray.get(groupPosition).get(childPosition).getName();            String t = account +"          "+name;            Log.e("sumlist", "info is " +t);            title.setText(t);            return convertView;        }        public boolean isChildSelectable(int groupPosition, int childPosition) {            // TODO Auto-generated method stub            return true;        }            }

代碼摘自現在的某個項目。

類似與BaseAdapter的關鍵getView方法，這裡比較重要的是getGroupView和getChildView方法，其實內部實現都是類似的。