android 适配器Adpter的使用总结 之 BaseExpandableListAdapter

android 适配器Adpter的使用总结 之 BaseExpandableListAdapter

2011-06-20 23:37 by 雪夜&流星, 94 visits,
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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：




View
Code

<?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>




View
Code

<?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：




View
Code
数据填充对象的构造、数据的封装：

public class 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
private int expandedGroupLayout;
private int collapsedGroupLayout;
private String[] groupFrom;
private int[] groupTo;
private int childLayout;
private int lastChildLayout;
private String[] childFrom;
private int[] 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
public int getGroupCount() {
// TODO Auto-generated method stub
return groupData.size();
}

//获取group的id
@Override
public long 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
public boolean isChildSelectable(int groupPosition, int childPosition) {
// TODO Auto-generated method stub
return true;
}

//获取子节点的数量
@Override
public int 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
public long 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;
}
}




View
Code

public class ListSimpleExpandableList extends Activity{
private static final String ICON="ICON";
private static final String NAME = "NAME";
private static final String IS_EVEN = "IS_EVEN";

private ExpandableListAdapter mAdapter;
private ExpandableListView expandableListView;
protected void 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。