public class Expandable_test extends Activity {  private ExpandableListView listView;  private Map<String, List<String>> dataset = new HashMap<>();  private String[] parentList = new String[]{"第一個菜單", "第二個菜單"};  private ExpandableListViewAdpter adpter;  private Context mContext = this;  @Override  protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_expandable_test);    listView=(ExpandableListView)findViewById(R.id.expandableListViewtext);    adpter=new ExpandableListViewAdpter(this,parentList);    listView.setAdapter(adpter);  }}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  xmlns:app="http://schemas.android.com/apk/res-auto"  xmlns:tools="http://schemas.android.com/tools"  android:layout_width="match_parent"  android:layout_height="match_parent"  tools:context="com.fae.mobile.testActivity.Expandable_test"><ExpandableListView  android:layout_width="match_parent"  android:layout_height="wrap_content"  android:id="@+id/expandableListViewtext"></ExpandableListView></LinearLayout>

public class ExpandableListViewAdpter extends BaseExpandableListAdapter {  private Context mContext;  private Map<String, List<String>> dataset = new HashMap<>();  private String[] parentList = new String[]{"第一個菜單", "第二個菜單"};  private String[][] chdrenList=new String[][]      {{"菜單1","菜單1","菜單1","菜單1","菜單1","菜單1"},{"菜單2","菜單2","菜單2","菜單2","菜單2"}};  public ExpandableListViewAdpter(Context context, String[] parentList){    this.mContext=context;    this.dataset=dataset;    this.parentList=parentList;  }  @Override  public int getGroupCount() {    return parentList.length;  }  @Override  public int getChildrenCount(int groupPosition) {    return chdrenList[groupPosition].length;  }  @Override  public Object getGroup(int groupPosition) {    return parentList[groupPosition];  }  @Override  public Object getChild(int groupPosition, int childPosition) {    return chdrenList[groupPosition][childPosition];  }  @Override  public long getGroupId(int groupPosition) {    return groupPosition;  }  @Override  public long getChildId(int groupPosition, int childPosition) {    return childPosition;  }  @Override  public boolean hasStableIds() {    return true;  }  @Override  public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {    GroupViewHolder holder=null;    if(convertView==null){      convertView = LayoutInflater.from(mContext).inflate(R.layout.itemlayoutexpandable, null);      holder=new GroupViewHolder();      holder.text=(TextView)convertView.findViewById(R.id.item_text);      convertView.setTag(holder);    }    else {      holder=(GroupViewHolder)convertView.getTag();    }    holder.text.setText(parentList[groupPosition]);    return convertView;  }  @Override  public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {    ChildViewHolder holder=null;      if(convertView==null){        convertView = LayoutInflater.from(mContext).inflate(R.layout.itemlayoutexpandable, null);        holder=new ChildViewHolder();        holder.text=(TextView)convertView.findViewById(R.id.item_text);        convertView.setTag(holder);    }    else {        holder=(ChildViewHolder)convertView.getTag();      }      holder.text.setText(chdrenList[groupPosition][childPosition]);    return convertView;  }  @Override  public boolean isChildSelectable(int groupPosition, int childPosition) {    return true;  }  class GroupViewHolder {    TextView text;  }  class ChildViewHolder {    TextView text;  }}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  android:layout_width="match_parent"  android:layout_height="match_parent"><TextView  android:layout_width="match_parent"  android:layout_height="wrap_content"  android:gravity="bottom"  android:id="@+id/item_text"/></LinearLayout>