android 适配器Adpter的使用总结 之 BaseExpandableListAdapter

转载请标明出处：http://www.cnblogs.com/tanlon/archive/2011/06/20/2085583.html

通过前面三篇文章:

Android 适配器Adapter的学习:http://www.cnblogs.com/tanlon/archive/2011/05/21/2053009.html

Android 适配器Adpter的使用总结:http://www.cnblogs.com/tanlon/archive/2011/06/20/2084901.html

Android 适配器Adpter的使用总结 之 CursorAdpter：http://www.cnblogs.com/tanlon/archive/2011/06/20/2085562.html

我们对Adpter有了较深的理解之后，我们来了解一下BaseExpandableListAdapter也就是二级树ExpandableListView的数据填充器。

我们应该先了解一下关于BaseExpandableListAdapter中的一些方法的含义和用法：

http://www.cnblogs.com/over140/archive/2011/01/18/1937921.html

如我的上篇博文<Android 适配器Adpter的使用总结 之 CursorAdpter>提到的BaseExpandableListAdapter则是实现了ExpandableListAdpter、HeterogeneousExpandableList接口，同理CursorTreeAdapter继承了BaseExpandableListAdapter，并且衍生出了ResourceCusorTreeAdapter，由ResourceCusorTreeAdapter又衍生出了SimpleCursorTreeAdapter。除此之外还有SimpleExpandableListAdapter也是继承自BaseExpandableListAdapter.

在这里还是以SimpleExpandableListAdapter为例，做一个小demo：

布局文件：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent">
   <ExpandableListView android:layout_height="fill_parent" 
   android:layout_width="fill_parent" android:id="@+id/expandableListView"/>
</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:gravity="center">
<TextView
android:id="@+id/expandablelistview_tv"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:text="expandablelistview_tv"
android:layout_centerVertical="true"
android:paddingLeft="50dp"
android:textSize="24dp"
/>
</RelativeLayout>

数据填充器：

publicclass ListSimpleExpandableListAdapter extends SimpleExpandableListAdapter{
    private Context context;
    private List<Map<String, String>> groupData =new ArrayList<Map<String, String>>();//装载group数据
private List<List<Map<String, String>>> childData =new ArrayList<List<Map<String, String>>>();//装载child数据
privateint expandedGroupLayout;
    privateint collapsedGroupLayout; 
    private String[] groupFrom;
    privateint[] groupTo;
    privateint childLayout;
    privateint lastChildLayout;
    private String[] childFrom;
    privateint[] childTo;
    //构造器
public ListSimpleExpandableListAdapter(Context context,
            List<Map<String, String>> groupData, int expandedGroupLayout,
            int collapsedGroupLayout, String[] groupFrom, int[] groupTo,
            List<List<Map<String, String>>> childData,
            int childLayout, int lastChildLayout, String[] childFrom,
            int[] childTo) {
        super(context, groupData, expandedGroupLayout, collapsedGroupLayout, groupFrom,
                groupTo, childData, childLayout, lastChildLayout, childFrom, childTo);
        // TODO Auto-generated constructor stub
this.context=context;
        this.groupData=groupData;
        this.childData=childData;
        this.expandedGroupLayout=expandedGroupLayout;
        this.collapsedGroupLayout=collapsedGroupLayout;
        this.groupFrom=groupFrom;
        this.groupTo=groupTo;
        this.childLayout=childLayout;
        this.lastChildLayout=lastChildLayout;
        this.childFrom=childFrom;
        this.childTo=childTo;    
        
    }

    //获取group对象
    @Override
    public Object getGroup(int groupPosition) {
        // TODO Auto-generated method stub
return groupData;
    }

    //获取group对象的数量
    @Override
    publicint getGroupCount() {
        // TODO Auto-generated method stub
return groupData.size();
    }

    //获取group的id
    @Override
    publiclong getGroupId(int groupPosition) {
        // TODO Auto-generated method stub
return groupPosition;
    }

    @Override
    public View getGroupView(int groupPosition, boolean isExpanded,
            View convertView, ViewGroup parent) {
        // TODO Auto-generated method stub
        GroupHolder groupHolder;
        if(convertView==null){
            convertView=LayoutInflater.from(context).inflate(expandedGroupLayout, null);
            groupHolder=new GroupHolder();
//            groupHolder.imageView=(ImageView) convertView.findViewById(R.id.expandablelistview_iv);
            groupHolder.textView=(TextView) convertView.findViewById(R.id.expandablelistview_tv);
            convertView.setTag(groupHolder);
        }else{
            groupHolder=(GroupHolder) convertView.getTag();
        }
//        groupHolder.imageView.setImageResource(Integer.parseInt(groupData.get(groupPosition).get(groupFrom[0]).toString()));
        groupHolder.textView.setText(groupData.get(groupPosition).get(groupFrom[1]).toString());
        return convertView;
    }

    //子节点是否被选中
    @Override
    publicboolean isChildSelectable(int groupPosition, int childPosition) {
        // TODO Auto-generated method stub
returntrue;
    }

    //获取子节点的数量
    @Override
    publicint getChildrenCount(int groupPosition) {
        // TODO Auto-generated method stub
return childData.get(groupPosition).size();
    }

    //获取子节点对象
    @Override
    public Object getChild(int groupPosition, int childPosition) {
        // TODO Auto-generated method stub
return childData.get(groupPosition).get(childPosition);
    }

    //获取子节点id
    @Override
    publiclong getChildId(int groupPosition, int childPosition) {
        // TODO Auto-generated method stub
return childPosition;
    }

    @Override
    public View getChildView(int groupPosition, int childPosition,
            boolean isLastChild, View convertView, ViewGroup parent) {
        // TODO Auto-generated method stub
        ChildHolder childHolder;
        if(convertView==null){
            convertView=LayoutInflater.from(context).inflate(childLayout, null);
            childHolder=new ChildHolder();
            childHolder.imageView=(ImageView) convertView.findViewById(R.id.listitem_pic);
            childHolder.title=(TextView) convertView.findViewById(R.id.listitem_title);
            childHolder.content=(TextView) convertView.findViewById(R.id.listitem_content);
            convertView.setTag(childHolder);
        }else{
            childHolder=(ChildHolder) convertView.getTag();
        }
        childHolder.imageView.setImageResource(Integer.parseInt(childData.get(groupPosition).get(childPosition).get(childFrom[0]).toString()));
        childHolder.title.setText(childData.get(groupPosition).get(childPosition).get(childFrom[1]).toString());
        childHolder.content.setText(childData.get(groupPosition).get(childPosition).get(childFrom[2]).toString());
        return convertView;
    }

    class GroupHolder{
        ImageView imageView;
        TextView textView;
    }
    
    class ChildHolder{
        ImageView imageView;
        TextView title;
        TextView content;
    }
}

publicclass ListSimpleExpandableList extends Activity{
    privatestaticfinal String ICON="ICON";
    privatestaticfinal String NAME ="NAME";
    privatestaticfinal String IS_EVEN ="IS_EVEN";
        
    private ExpandableListAdapter mAdapter;
    private ExpandableListView expandableListView;
    protectedvoid onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
super.onCreate(savedInstanceState);        
        setContentView(R.layout.groupexpandablelist);
        List<Map<String, String>> groupData =new ArrayList<Map<String, String>>();
        List<List<Map<String, String>>> childData =new ArrayList<List<Map<String, String>>>();
        for (int i =0; i <20; i++) {
            Map<String, String> curGroupMap =new HashMap<String, String>();
            groupData.add(curGroupMap);
            curGroupMap.put(ICON, String.valueOf(R.drawable.icon));
            curGroupMap.put(NAME, "Group "+ i);
            curGroupMap.put(IS_EVEN, (i %2==0) ?"This group is even" : "This group is odd");
            
            List<Map<String, String>> children =new ArrayList<Map<String, String>>();
            for (int j =0; j <15; j++) {
                Map<String, String> curChildMap =new HashMap<String, String>();
                curChildMap.put(ICON, String.valueOf(R.drawable.icon));
                curChildMap.put(NAME, "Child "+ j);
                curChildMap.put(IS_EVEN, (j %2==0) ?"This child is even" : "This child is odd");
                children.add(curChildMap);
            }
            childData.add(children);
        }
        expandableListView=(ExpandableListView) findViewById(R.id.expandableListView);
        mAdapter=new ListSimpleExpandableListAdapter(this, groupData, R.layout.groupexpandablelist_item, 0, new String[] { ICON ,NAME, IS_EVEN }, null, childData, R.layout.listsimple_item, 0,  new String[] { ICON ,NAME, IS_EVEN }, null);
        expandableListView.setAdapter(mAdapter);
        //传入null则是消除箭头，如果想替换成自己的图标则传入一个drawable即可
//        this.expandableListView.setGroupIndicator(null);
    }
    
}

有什么不对的地方还望大牛多多指教！
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很晚了，睡觉去了，明天有机会再写。