Android ExpandableListView的使用

ExpandableListView是android中可以实现下拉list的一个控件，具体的实现方法如下：

首先：在layout的xml文件中定义一个ExpandableListView 

 

 

<LinearLayout    
    android:id="@+id/linearLayout"   
    android:layout_width="fill_parent"    
    android:layout_height="fill_parent"   
    androidrientation="vertical"   
    >   
       
    <ExpandableListView   
    android:id="@+id/expandableListView"   
    android:layout_width="fill_parent"   
    android:layout_height="wrap_content"   
        />   
</LinearLayout>  

 

定义两个List，用来存放控件中Group/Child中的String

 

private List<String> groupArray;   
private List<List<String>> childArray;  

 

对这两个List进行初始化，并插入一些数据

 

groupArray = new ArrayList<String>();
  
childArray = new ArrayList<List<String>>();
  

  
groupArray.add("第一行");
  
groupArray.add("第二行");
  

  
List<String> tempArray = new ArrayList<String>();
  
tempArray.add("第一条");
  
tempArray.add("第二条");
  
tempArray.add("第三条");
  

  
for(int index = 0; index <groupArray.size(); ++index)
  
{
  
    childArray.add(tempArray);
  
}  

  定义ExpandableListView的Adapter

 

//ExpandableListView的Adapter
  
public class ExpandableAdapter extends BaseExpandableListAdapter
  
{
  
    Activity activity;
  
    
  
    public ExpandableAdapter(Activity a)
  
    {
  
        activity = a;
  
    }
  
    public Object getChild(int groupPosition, int childPosition)
  
    {
  
        return childArray.get(groupPosition).get(childPosition);
  
    }
  
    public long getChildId(int groupPosition, int childPosition)
  
    {
  
        return childPosition;
  
    }
  
    public int getChildrenCount(int groupPosition)
  
    {
  
        return childArray.get(groupPosition).size();
  
    }
  
    public View getChildView(int groupPosition, int childPosition,
  
            boolean isLastChild, View convertView, ViewGroup parent)
  
    {
  
        String string = childArray.get(groupPosition).get(childPosition);
  
        return getGenericView(string);
  
    }
  
    // group method stub
  
    public Object getGroup(int groupPosition)
  
    {
  
        return groupArray.get(groupPosition);
  
    }
  
    public int getGroupCount()
  
    {
  
        return groupArray.size();
  
    }
  
    public long getGroupId(int groupPosition)
  
    {
  
        return groupPosition;
  
    }
  
    public View getGroupView(int groupPosition, boolean isExpanded,
  
            View convertView, ViewGroup parent)
  
    {
  
        String string = groupArray.get(groupPosition);
  
        return getGenericView(string);
  
    }
  
    // View stub to create Group/Children 's View
  
    public TextView getGenericView(String string)
  
    {
  
        // Layout parameters for the ExpandableListView
  
        AbsListView.LayoutParams layoutParams = new AbsListView.LayoutParams(
  
                ViewGroup.LayoutParams.FILL_PARENT, 64);
  
        TextView text = new TextView(activity);
  
        text.setLayoutParams(layoutParams);
  
        // Center the text vertically
  
        text.setGravity(Gravity.CENTER_VERTICAL | Gravity.LEFT);
  
        // Set the text starting position
  
        text.setPadding(36, 0, 0, 0);
  
        text.setText(string);
  
        return text;
  
    }
  
    public boolean hasStableIds()
  
    {
  
        return false;
  
    }
  
    public boolean isChildSelectable(int groupPosition, int childPosition)
  
    {
  
        return true;
  
    }
  
}  

 

最后，给定义好的ExpandableListView添加上Adapter

 

 

ExpandableListView expandableListView = (ExpandableListView)findViewById(R.id.expandableListView);
  
expandableListView.setAdapter(new ExpandableAdapter(Main.this));  

 

运行即可见效果~~~