Android ExpandableListView的应用

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?

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<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>  

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定义两个List，用来存放控件中Group/Child中的String

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

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对这两个List进行初始化，并插入一些数据

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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

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//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;      }  }  

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最后，给定义好的ExpandableListView添加上Adapter

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

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运行即可见效果~~~