BaseExpandableListAdapter-优快云博客

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publicabstractclass
BaseExpandableListAdapter
extendsObject
implementsExpandableListAdapterHeterogeneousExpandableList
ClassOverview
BaseclassforaExpandableListAdapterusedtoprovidedataandViewsfromsomedatatoanexpandablelistview.
AdaptersinheritingthisclassshouldverifythatthebaseimplementationsofgetCombinedChildId(long,long)
andgetCombinedGroupId(long)arecorrectingeneratinguniqueIDsfromthegroup/childrenIDs.
BaseExpandableListAdapter实现了接口 ExpandableListAdapter
BaseExpandableListAdapter的子类
CursorTreeAdapter
ResourceCursorTreeAdapter
SimpleCursorTreeAdapter
BaseExpandableListAdapter主要实现了ExpandableListAdapter接口的四个方法
getCombinedChildId(long,long)
用于产生child的id。注意id一定要是唯一.在BaseExpandableListAdapter实现里把最高位置成了1。也就是说该id始终是个负数
getCombinedGroupId(long)
用于产生group的id。注意id一定要是唯一.在BaseExpandableListAdapter实现里把最高位置成了0。也就是说该id始终是个正数
void onGroupCollapsed(intgroupPosition)
Calledwhenagroupiscollapsed.
Group收缩时调用。好像只是个监听接口。当Group收缩时，ExpandableListView回调用。
void onGroupExpanded(intgroupPosition)
Calledwhenagroupisexpanded.
Group展开时调用Buthowtouse?
Group展开时调用。好像只是个监听接口。当Group展开时，ExpandableListView回调用
注意：对于onGroupCollapsed和onGroupExpanded，没发现BaseExpandableListAdapter在两个函数中实现什么功能。
可能只是个空实现。目的就为了让用户不再浪费时间去做个空实现。
还未实现的ExpandableListAdapter接口方法有六个：
abstractObject getChild(intgroupPosition,intchildPosition)
Getsthedataassociatedwiththegivenchildwithinthegivengroup.
abstractlong getChildId(intgroupPosition,intchildPosition)
GetstheIDforthegivenchildwithinthegivengroup.
abstractView getChildView(intgroupPosition,intchildPosition,booleanisLastChild,ViewconvertView,ViewGroupparent)
GetsaViewthatdisplaysthedataforthegivenchildwithinthegivengroup.
abstractint getChildrenCount(intgroupPosition)
Getsthenumberofchildreninaspecifiedgroup.
abstractObject getGroup(intgroupPosition)
Getsthedataassociatedwiththegivengroup.
abstractint getGroupCount()
Getsthenumberofgroups.
abstractlong getGroupId(intgroupPosition)
GetstheIDforthegroupatthegivenposition.
abstractView getGroupView(intgroupPosition,booleanisExpanded,ViewconvertView,ViewGroupparent)
GetsaViewthatdisplaysthegivengroup.
实例1：
HelloExpandableListAdapter.java文件
importjava.util.List;
importandroid.app.Activity;
importandroid.os.Bundle;
importjava.util.ArrayList;
importandroid.app.ExpandableListActivity;
importandroid.content.Context;
importandroid.graphics.drawable.Drawable;
importandroid.os.CountDownTimer;
importandroid.util.Log;
importandroid.view.LayoutInflater;
importandroid.view.View;
importandroid.view.ViewGroup;
importandroid.widget.BaseExpandableListAdapter;
importandroid.widget.ExpandableListAdapter;
importandroid.widget.ExpandableListView;
importandroid.widget.ImageView;
importandroid.widget.LinearLayout;
importandroid.widget.ProgressBar;
importandroid.widget.TextView;
importandroid.widget.ExpandableListView.OnGroupClickListener;
importandroid.widget.ExpandableListView.OnChildClickListener;
publicclass HelloExpandableListAdapterextendsActivity{
privateString mMailboxList[]={
"Inbox","Sentbox","Draft",
"Outbox","Emailinbox","Conversation",
"Trash","Myfolders"
};

finalstaticString mLoading="Loadingmessage...";

privateString mSender[][]={{"Andrew1","Andrew2","Andrew3","Andrew4","Andrew5","Andrew6"},
{"Jeff1","Jeff2","Jeff3","Jeff4","Jeff5","Jeff6","Jeff7"},
{"ED1","ED2","ED3","ED4","ED5"},
{"Rachel1","Rachel2","Rachel3","Rachel4"},
{"Sean1","Sean2","Sean3","Sean4","Sean5"},
{"Karen1","Karen2","Karen3","Karen4","Karen5","Karen6","Karen7"},
{"Lisa1","Lisa2","Lisa3","Lisa4","Lisa5"},
{"Rain1","Rain2","Rain3","Rain4","Rain5"}};
privateString mMailContext[][]={{"I'mgoingtogotowatchmovie!","Hello....","Nicetomeetyou","Callmeplz..","hi","Callmeplz.."},
{"hello","Callmeplz..","hello","I'mgoingtogotowatchmovie!","Hello....","Nicetomeetyou","Callmeplz.."},
{"hi","Callmeplz..","hi","Callmeplz..","hi"},
{"I'mgoingtogotowatchmovie!","Hello....","Nicetomeetyou","Callmeplz.."},
{"hi","Callmeplz..","hi","Callmeplz..","hi"},
{"12312412","12414124","12412421","458645754","dfgsdgsdf","sdfgdfgh","sdfgdsfgh"},
{"vclkj","lkvoajh","alskdjfoivj","jvlkjasldkf","79837214"},
{"975432","kbvhuoisj","4362435,","342532","236dgasdt"}};

privateString mDate[][]={{"11/22/09","11/23/08","09/11/07","02/03/05","00/09/09","11/11/11"},
{"12/12/12","12/25/09","01/03/09","11/22/09","11/23/08","09/11/07","02/03/05"},
{"00/09/09","11/11/11","12/12/12","12/25/09","01/03/09"},
{"11/22/09","11/23/08","09/11/07","02/03/05"},
{"00/09/09","11/11/11","12/12/12","12/25/09","01/03/09"},
{"12/12/12","12/25/09","01/03/09","11/22/09","11/23/08","09/11/07","02/03/05"},
{"00/09/09","11/11/11","12/12/12","12/25/09","01/03/09"},
{"00/09/09","11/11/11","12/12/12","12/25/09","01/03/09"}};
ExpandableListAdaptermAdapter;
protectedArrayList<GroupItem> groupList=newArrayList<GroupItem>();
ArrayList<ArrayList<ChildItem>> childrenList=newArrayList<ArrayList<ChildItem>>();
/**Calledwhentheactivityisfirstcreated.*/
@Override
publicvoid onCreate(BundlesavedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ExpandableListViewexpandableListView=(ExpandableListView)findViewById(R.id.ExpandableListView01);

//initializingExpandedmailboxlistdata
for(inti=0;i<mMailboxList.length;i++){
GroupItemitem=newGroupItem( mMailboxList[i]); groupList.add(item); ArrayList<ChildItem>childItems=newArrayList<ChildItem>(); ChildItemitems=newChildItem(mLoading,null,null); childItems.add(items); childrenList.add(childItems); } //Setupouradapter mAdapter=newExpandedMailboxListAdapter(this,groupList,childrenList); expandableListView.setAdapter(mAdapter); expandableListView.setGroupIndicator(null);//Groupindicatordisable expandableListView.setOnGroupClickListener(newOnGroupClickListener(){ publicbooleanonGroupClick(ExpandableListViewmExpandableList,Viewarg1, finalintgroupPosition,longid){ //这里的id就是getGroupId中得到的 Log.i("hubin","G:"+groupPosition+"id:"+id); newCountDownTimer(3000,50){ publicvoidonTick(longmillisUntilFinished){ } publicvoidonFinish(){ expandableListChange(groupPosition); } }.start(); returnfalse; } }); expandableListView.setOnChildClickListener(newOnChildClickListener(){ publicbooleanonChildClick(ExpandableListViewparent,Viewv,intgroupPosition,intchildPosition,longid) { //这里的id就是getChildId中得到的 Log.i("hubin","c:"+groupPosition+"id:"+id); returnfalse; } } ); } privatevoidexpandableListChange(intgroupPosition){ ArrayList<ChildItem>childrenItemList=childrenList.get(groupPosition); childrenItemList.clear(); for(inti=0;i<mSender[groupPosition].length;i++){ ChildItemitems=newChildItem(mSender[groupPosition][i],mMailContext[groupPosition][i],mDate[groupPosition][i]); childrenItemList.add(i,items); } ((BaseExpandableListAdapter)mAdapter).notifyDataSetChanged(); } } classExpandedMailboxListAdapterextendsBaseExpandableListAdapter{ privateTextViewmMailbox; privateImageViewmMailboxIcon; Contextcontext; ArrayList<GroupItem>groupList; ArrayList<ArrayList<ChildItem>>childrenList; ExpandedMailboxListAdapter(Contextcontext,ArrayList<GroupItem>groupList,ArrayList<ArrayList<ChildItem>>childrenList) { this.context=context; this.groupList=groupList; this.childrenList=childrenList; } /* *(non-Javadoc) *@seeandroid.widget.ExpandableListAdapter#getChild(int,int) */ publicObjectgetChild(intarg0,intarg1){ returnnull; } publiclonggetChildId(intgroupPosition,intchildPosition){ returnchildPosition; } publicintgetChildrenCount(intgroupPosition){ returnchildrenList.get(groupPosition).size(); } finalstaticStringmLoading="Loadingmessage..."; /** *Getchildviewandsetchilddata. *convertViewisreusedview */ publicViewgetChildView(intgroupPosition,intchildPosition,booleanisLastChild,ViewconvertView,ViewGroupparent){ LinearLayoutmTodoView=null; TextViewmailSender; TextViewcontent; TextViewsubDate; ProgressBarprogress; if(convertView==null){ LayoutInflatervi=null; vi=(LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); mTodoView=(LinearLayout)vi.inflate(R.layout.listlayout_child,parent,false); } else{ mTodoView=(LinearLayout)convertView; } progress=(ProgressBar)mTodoView.findViewById(R.id.child_progressbar); mailSender=(TextView)mTodoView.findViewById(R.id.child_text1); content=(TextView)mTodoView.findViewById(R.id.child_text2); subDate=(TextView)mTodoView.findViewById(R.id.child_text3); ChildItemchildItem=childrenList.get(groupPosition).get(childPosition); if(childItem.getSender()==mLoading){ progress.setVisibility(View.VISIBLE); progress.setIndeterminate(true); mailSender.setText(childItem.getSender()); }else{ progress.setVisibility(View.GONE); mailSender.setText(childItem.getSender()); } if(childItem.getContent()==null){ content.setVisibility(View.GONE); }else{ content.setVisibility(View.VISIBLE); content.setText(childItem.getContent()); } if(childItem.getDate()==null){ subDate.setVisibility(View.GONE); }else{ subDate.setVisibility(View.VISIBLE); subDate.setText(childItem.getDate()); } returnmTodoView; } /* *(non-Javadoc) *@seeandroid.widget.ExpandableListAdapter#getGroup(int) */ publicObjectgetGroup(intgroupPosition){ returnnull; } publicintgetGroupCount(){ returngroupList.size(); } publiclonggetGroupId(intgroupPosition){ returngroupPosition; } /** *GetGroupviewandsetgroupdata. *convertViewisreusedview */ publicViewgetGroupView(intgroupPosition,booleanisExpanded,ViewconvertView,ViewGroupparent){ LinearLayoutmTodoView=null; if(convertView==null){ LayoutInflatervi=null; vi=(LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); mTodoView=(LinearLayout)vi.inflate(R.layout.listlayout_group,parent,false); } else{ mTodoView=(LinearLayout)convertView; } mMailbox=(TextView)mTodoView.findViewById(R.id.text1); mMailbox.setText(groupList.get(groupPosition).getMailbox()); returnmTodoView; } //IndicateswhetherthechildandgroupIDsarestable publicbooleanhasStableIds(){ returntrue; } //Whetherthechildatthespecifiedpositionisselectable. publicbooleanisChildSelectable(intgroupPosition,intchildPosition){ returntrue; } publiclonggetCombinedChildId(longgroupId,longchildId) { longres=super.getCombinedChildId(groupId,childId); Log.i("hubin","cc:"+res); returnres; } publiclonggetCombinedGroupId(longgroupId) { longres=super.getCombinedGroupId(groupId); Log.i("hubin","cg:"+res); returnres; } publicvoidonGroupCollapsed(intgroupPosition) { Log.i("hubin","Collapsed"); } publicvoidonGroupExpanded(intgroupPosition) { Log.i("hubin","Expanded"); } } /** *GroupItemclass *initGroupitemdatainlistlayoutsample12sml_group.xml *Groupitemhasownchilditem'sreference */ classGroupItem{ StringmMailbox; publicGroupItem(StringMailbox){ mMailbox=Mailbox; } publicStringgetMailbox(){ returnmMailbox; } } /** *ChildItemclass *initchilditemdatainlistlayoutsample12sml_child.xml */ classChildItem{ privateStringmSender; privateStringmContext; privateStringmDate; publicChildItem(StringSender,StringContext,StringDate){ mSender=Sender; mContext=Context; mDate=Date; } publicStringgetSender(){ returnmSender; } publicStringgetContent(){ returnmContext; } publicStringgetDate(){ returnmDate; }

}

main.xml文件
<?xmlversion="1.0"encoding="utf-8"?>
<LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello"
/>
< ExpandableListView android:id="@+id/ExpandableListView01"android:layout_width="wrap_content"android:layout_height="wrap_content">

</ExpandableListView>
</LinearLayout>
listlayout_group.xml文件
<?xmlversion="1.0"encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:paddingBottom="8dip"
android:orientation="horizontal"
android:paddingTop="5dip"
android:layout_height="65.33dp"
android:paddingLeft="4.66dp"
android:paddingRight="13.33dp">
<TextView
android:id="@+id/text1"
android:layout_marginLeft="6dip"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:singleLine="true"
android:gravity="center_vertical"
android:layout_gravity="center_vertical"
/>
</LinearLayout>
listlayout_child.xml文件
<?xmlversion="1.0"encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:orientation="vertical"
android:paddingRight="13.33dp"
android:layout_height="65.33dp"
android:paddingLeft="31.9dp"
android:gravity="center_vertical">
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_height="wrap_content"
android:layout_width="fill_parent"
android:orientation="horizontal">
<ProgressBar
android:id="@+id/child_progressbar"
android:layout_width="32dp"
android:layout_height="32dp"
android:layout_marginRight="5dp"
android:minHeight="32dp"
android:maxHeight="32dp"
android:minWidth="32dp"
android:maxWidth="32dp"
android:indeterminateOnly="false">
</ProgressBar>
<TextView
android:id="@+id/child_text1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:singleLine="true"/>
</LinearLayout>

<LinearLayout
android:orientation="horizontal"
android:layout_height="wrap_content"
android:layout_width="fill_parent"
android:layout_marginTop="6dip">
<TextView
android:id="@+id/child_text2"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:singleLine="true"
android:layout_weight="1"/>
<TextView
android:id="@+id/child_text3"
android:layout_height="wrap_content"
android:layout_width="wrap_content"/>
</LinearLayout>

</LinearLayout>