Question

I need to define the structure of ExpandableListView in xml file manually.
Is there any guide or example of doing this?

Thanks

Answer 1

I run into this two days ago. Here’s my solution:

First extend ExpandableListActivity and override the onCreate() method like this:

public class ExpandableExample extends ExpandableListActivity {
    @Override
    public void onCreate() {
        super.onCreate(savedInstanceState);
        setListAdapter(new BaseExpandableListAdapterExample());
    }
}

The definition of BaseExpanableListAdapterExample is (inner class of ExpandableExample):

protected class BaseExpandableListAdapterExample extends BaseExpandableListAdapter {
}

Then you need to implement getChildView and getGroupView. What I did was:

public View getGroupView(int groupPosition, boolean isExpanded,
                         View convertView, ViewGroup parent) {
    View groupRow = getLayoutInflater().inflate(R.layout.group_row, null);
    TextView textView = (TextView) groupRow.findViewById(R.id.text_group);
    textView.setText(getGroup(groupPosition).toString());
    return groupRow;
}

public View getChildView(int groupPosition, int childPosition,
                         boolean isLastChild, View convertView, ViewGroup parent) {
    View childRow = getLayoutInflater().inflate(R.layout.child_row, null);
    TextView textView = (TextView) childRow.findViewById(R.id.text_child);
    textView.setText(getChild(groupPosition, childPosition).toString());
    return childRow;
}

Then you need to define both group_row.xml and child_row.xml under /res/layout/ directory. For example, my group_row.xml is as follows:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >
    <TextView
        android:id="@+id/text_element"
        android:layout_width="fill_parent"
        android:layout_height="48dip"
        android:textSize="20sp"
        android:textColor="#fff"
        android:layout_marginLeft="48dip"
        android:gravity="center_vertical" />
</RelativeLayout>

Hope it helps. Comment if you have any question.