How to create ExpandableListView keeping some child fixed? - android-listview

Question

I want to create an expandable list view Keeping some child visible,where as I want to show rest on click.
Please suggest what is the best approach in such scenario,if any custom element or any tutorial as such.
Many Thanks,

Answer 1

This will be helpful to you.
Adapter class:-
public class MyExpandableAdapter extends BaseExpandableListAdapter {
private Activity activity;
private ArrayList<Object> childtems;
private LayoutInflater inflater;
private ArrayList<String> parentItems, child;
public MyExpandableAdapter(ArrayList<String> parents,
ArrayList<Object> childern) {
this.parentItems = parents;
this.childtems = childern;
}
public void setInflater(LayoutInflater inflater, Activity activity) {
this.inflater = inflater;
this.activity = activity;
}
#Override
public View getChildView(int groupPosition, final int childPosition,
boolean isLastChild, View convertView, ViewGroup parent) {
child = (ArrayList<String>) childtems.get(groupPosition);
TextView textView = null;
if (convertView == null) {
convertView = inflater.inflate(R.layout.group, null);
}
textView = (TextView) convertView.findViewById(R.id.textView1);
textView.setText(child.get(childPosition));
convertView.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View view) {
Toast.makeText(activity, child.get(childPosition),
Toast.LENGTH_SHORT).show();
}
});
return convertView;
}
#Override
public View getGroupView(int groupPosition, boolean isExpanded,
View convertView, ViewGroup parent) {
if (convertView == null) {
convertView = inflater.inflate(R.layout.row, null);
}
((CheckedTextView) convertView).setText(parentItems
.get(groupPosition));
((CheckedTextView) convertView).setChecked(isExpanded);
return convertView;
}
#Override
public Object getChild(int groupPosition, int childPosition) {
return null;
}
#Override
public long getChildId(int groupPosition, int childPosition) {
return 0;
}
#Override
public int getChildrenCount(int groupPosition) {
return ((ArrayList<String>) childtems.get(groupPosition)).size();
}
#Override
public Object getGroup(int groupPosition) {
return null;
}
#Override
public int getGroupCount() {
return parentItems.size();
}
#Override
public void onGroupCollapsed(int groupPosition) {
super.onGroupCollapsed(groupPosition);
}
#Override
public void onGroupExpanded(int groupPosition) {
super.onGroupExpanded(groupPosition);
}
#Override
public long getGroupId(int groupPosition) {
return 0;
}
#Override
public boolean hasStableIds() {
return false;
}
#Override
public boolean isChildSelectable(int groupPosition, int childPosition) {
return false;
}
}
MainActivity is here.
public class MainActivity extends ExpandableListActivity {
private ArrayList<String> parentItems = new ArrayList<String>();
private ArrayList<Object> childItems = new ArrayList<Object>();
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// this is not really necessary as ExpandableListActivity contains
// an ExpandableList
// setContentView(R.layout.main);
ExpandableListView expandableList = getExpandableListView(); // you
// can
// use
// (ExpandableListView)
// findViewById(R.id.list)
expandableList.setDividerHeight(2);
expandableList.setGroupIndicator(null);
expandableList.setClickable(true);
setGroupParents();
setChildData();
MyExpandableAdapter adapter = new MyExpandableAdapter(parentItems,
childItems);
adapter.setInflater(
(LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE),
this);
expandableList.setAdapter(adapter);
expandableList.setOnChildClickListener(this);
}
public void setGroupParents() {
parentItems.add("Android");
parentItems.add("Core Java");
parentItems.add("Desktop Java");
parentItems.add("Enterprise Java");
}
public void setChildData() {
// Android
ArrayList<String> child = new ArrayList<String>();
child.add("Core");
child.add("Games");
childItems.add(child);
// Core Java
child = new ArrayList<String>();
child.add("Apache");
child.add("Applet");
child.add("AspectJ");
child.add("Beans");
child.add("Crypto");
childItems.add(child);
// Desktop Java
child = new ArrayList<String>();
child.add("Accessibility");
child.add("AWT");
child.add("ImageIO");
child.add("Print");
childItems.add(child);
// Enterprise Java
child = new ArrayList<String>();
child.add("EJB3");
child.add("GWT");
child.add("Hibernate");
child.add("JSP");
childItems.add(child);
}
}

Answer 2

At start open the groups you want to be fixed then implement this , specify the the groups postion
expandableList.setOnGroupClickListener(new OnGroupClickListener() {
#Override
public boolean onGroupClick(ExpandableListView parent, View v,
int groupPosition, long id) {
if(groupPosition==your group position){
return true; // This way the expander cannot be collapsed
}else{
return false;
}
}
});

Answer 3

Override onGroupCollapsed and onGroupExpanded of the ExpandableListView based on your needs.
EDITED: In addition: implement the mentioned setOnGroupClickListener, store the groupIDs within your view, and suppress the collapsing in onGroupCollapsed.