ExpandableListView（可展开的列表组件）使用方法

package com.example.expandablelist;

import android.os.Bundle;
import android.app.Activity;
import android.view.Gravity;
import android.view.Menu;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.BaseExpandableListAdapter;
import android.widget.ExpandableListAdapter;
import android.widget.ExpandableListView;
import android.widget.TextView;

public class MainActivity extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ExpandableListAdapter adapter = new BaseExpandableListAdapter() {
private String[] group = new String[]
{"G1","G2","G3"};
private String[][] child = new String[][]
{{"g1c1","g1c2","g1c3"},
{"g2c1","g2c2","g2c3"},
{"g3c1","g3c2","g3c3"}

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

@Override
public boolean hasStableIds() {
// TODO Auto-generated method stub
return false;
}

@Override
public View getGroupView(int groupPosition, boolean isExpanded,
View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
TextView textview =getTextView();
textview.setText(getGroup(groupPosition).toString());
return textview;
}

@Override
public long getGroupId(int groupPosition) {
// TODO Auto-generated method stub
return groupPosition;
}

@Override
public int getGroupCount() {
// TODO Auto-generated method stub
return group.length;
}

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

@Override
public int getChildrenCount(int groupPosition) {
// TODO Auto-generated method stub
return child[groupPosition].length;
}

@Override
public View getChildView(int groupPosition, int childPosition,
boolean isLastChild, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
TextView textview = getTextView();
textview.setText(getChild(groupPosition, childPosition).toString());
return textview;
}

private TextView getTextView() {
// TODO Auto-generated method stub
AbsListView.LayoutParams lp = new AbsListView.LayoutParams(ViewGroup.LayoutParams.FILL_PARENT,64);
TextView textview = new TextView(MainActivity.this);
textview.setLayoutParams(lp);
textview.setGravity(Gravity.CENTER_VERTICAL|Gravity.LEFT);
textview.setPadding(36,0,0,0);
textview.setTextSize(20);
return textview;
}

@Override
public long getChildId(int groupPosition, int childPosition) {
// TODO Auto-generated method stub
return childPosition;
}

@Override
public Object getChild(int groupPosition, int childPosition) {
// TODO Auto-generated method stub
return child[groupPosition][childPosition];
}
};
ExpandableListView expandListView=(ExpandableListView)findViewById(R.id.list);
expandListView.setAdapter(adapter);
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}

}