title: how to distinguish between same view (e.g. a +/- toggle button) in expandable listview row and open corresponding group on selection?
body: <p>I am using an ExpandableListView. Each group is populated from a custom view, which has a toggle type of button (+/-).</p>
  
  <p>I am able to open the corresponding group on selection. However, the state of toggle is not correct when scrolled. I'm kind of confused on how to use the tags and all.</p>
  
  <p>The code in getView is as follows:</p>
  
  <pre><code>if(convertView == null) {
          LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
          View root = inflater.inflate(R.layout.h_header_layout_exp_list, null);
  
          root.findViewById(R.id.call_icon).setOnClickListener(new View.OnClickListener() {
              @Override
              public void onClick(View v) {
                  operationExecutorFromExpList.launchDialer();
              }
          });
  
          view = root;
      }
      else{
          ((ImageView) convertView.findViewById(R.id.expander)).setTag(groupPosition);
          view = convertView;
      }
  
      final ImageView expandImageView = (ImageView) view.findViewById(R.id.expander);
      expandImageView.setOnClickListener(new View.OnClickListener() {
          @Override
          public void onClick(View v) {
              int imageId = isExpanded ? android.R.drawable.ic_input_add : R.drawable.ic_minus;
              expandImageView.setImageResource(imageId);
              operationExecutorFromExpList.animateGroup(isExpanded, groupPosition);
          }
      });
  </code></pre>