Listview with slide expandable details view

Question

in the App im developing, i got a List of messages with titel datum etc. When clicking on the Messagetitel i want to sliding expand this entry and show the Details, and some new buttons like "reply" , "delete" and "forward".

like:
- message
- message (clicked message)
details buttons delete , forward , reply
text
- message
- message

Here is what i did so far:

first my Model Class for the messages:

public class MyMessage {

private String from;
private String subject;
private String date;
private String message;

public MyMessage(String f, String s, String d, String m){
    from= f;
    subject= s;
    date = d;
    message= m;
}

public String getFrom() {
    return from;
}

public String getSubject() {
    return subject;
}

public String getDate() {
    return date;
}

public String getMessage() {
    return message;
}

}

my Custom Adapter:

public class NewAdapter extends BaseExpandableListAdapter {

public ArrayList<MyMessage> mMessage;
public LayoutInflater minflater;
 public Activity activity;

public NewAdapter(ArrayList<MyMessage> message){
    mMessage = message;
}

 public void setInflater(LayoutInflater mInflater, Activity act) {
      this.minflater = mInflater;
      activity = act;
     }

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

@Override
public long getChildId(int groupPosition, int childPosition) {
    // TODO Auto-generated method stub
    return 0;
}

@Override
public View getChildView(int groupPosition, int childPosition,
        boolean isLastChild, View convertView, ViewGroup parent) {

    TextView text = null;
    // TODO Auto-generated method stub
    if (convertView == null) {
           convertView = minflater.inflate(R.layout.message_details, null);
          }
    text = (TextView) convertView.findViewById(R.id.tv_message_text);
    text.setText(mMessage.get(childPosition).getMessage());
    return convertView;
}

@Override
public int getChildrenCount(int groupPosition) {
    // TODO Auto-generated method stub
    return 0;
}

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

@Override
public int getGroupCount() {
    // TODO Auto-generated method stub
    return 0;
}

@Override
public long getGroupId(int groupPosition) {
    // TODO Auto-generated method stub
    return 0;
}

@Override
public View getGroupView(int groupPosition, boolean isExpanded,
        View convertView, ViewGroup parent) {
    TextView from= null;
    TextView date = null;
    TextView subject= null;
    // TODO Auto-generated method stub

    if(convertView == null){
        convertView = minflater.inflate(R.layout.message_head, null);
    }
    from= (TextView) convertView.findViewById(R.id.tv_from);
    date = (TextView) convertView.findViewById(R.id.tv_date);
    subject= (TextView) convertView.findViewById(R.id.tv_subject);

    from.setText(mMessage.get(groupPosition).getfrom());
    date.setText(mMessage.get(groupPosition).getDate());
    subject.setText(mMessage.get(groupPosition).getSubject());


    return convertView;
}

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

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

}

my main Class:

public class Test extends ExpandableListActivity{

public ArrayList<MyMessage> message;
public ExpandableListView eListView;

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_test);

    eListView = getExpandableListView();

    message = createMessages();
    NewAdapter nAdapter = new NewAdapter(message);
    nAdapter
    .setInflater(
      (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE),
      this);
    getExpandableListView().setAdapter(nAdapter);

}

private ArrayList<MyMessage> createMessages() {

    ArrayList<MyMessage> m = new ArrayList<MyMessage>();
    MyMessage test1 = new MyMessage("test1", "testbetreff", "08.11.2013 / 09:44", "gaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaanz viel text und so");
    MyMessage test2 = new MyMessage("test2", "testbetreff", "08.11.2013 / 09:45", "gaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaanz viel text und so gaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaanz viel text und so");
    MyMessage test3 = new MyMessage("test3", "testbetreff", "08.11.2013 / 09:46", "gaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaanz viel text und so gaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaanz viel text und so gaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaanz viel text und so");
    MyMessage test4 = new MyMessage("test4", "testbetreff", "08.11.2013 / 09:47", "gaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaanz viel text und so gaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaanz viel text und so gaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaanz viel text und so gaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaanz viel text und so");

    m.add(test1);
    m.add(test2);
    m.add(test3);
    m.add(test4);

    return m;

}

}

i dont get any errors but my activity is blank. I tried to debug this but it never calls getchildview() or getgroupview() and i dont know why.

am im doing any big mistakes with the costum adapter ? thanks in advance

Answer 1

 @Override
    public int getChildrenCount(int groupPosition) {
        return 1; //just one children?
    }

    @Override
    public Object getGroup(int groupPosition) {
        return mMessage.get(groupPosition);
    }

    @Override
    public int getGroupCount() {
       return mMessage.size();
    }

    @Override
     public long getGroupId(int groupPosition) {
        return groupPosition;
     }

Try this... maybe it's not called because you said that the adapter has no items at all...