I want to add an image into some cells in ExpandableListI already search for answer on my question and I try to put
expListView.getLastVisiblePosition();
expListView.getFirstVisiblePosition();
And it isn't work. I can't do this in getView() in adapter, because I create cells dynamically by downloading data from database, and after it I can say which cell need image.
I also tried to do: Sometimes listView.getChildAt(int index) returns NULL (Android) Nullpointerexception on getChildAt GridView getChildAt() returns null No solution work. It is my code:
public class ExpandableListAdapter extends BaseExpandableListAdapter {
private Context _context;
private List<String> _listDataHeader; // header titles
// child data in format of header title, child title
private HashMap<String,String> _listDataChild;
public ExpandableListAdapter(Context context, List<String> listDataHeader,
HashMap<String, String> listChildData) {
this._context = context;
this._listDataHeader = listDataHeader;
this._listDataChild = listChildData;
}
@Override
public Object getChild(int groupPosition, int childPosititon) {
return this._listDataChild.get(this._listDataHeader.get(groupPosition));
}
@Override
public long getChildId(int groupPosition, int childPosition) {
return childPosition;
}
@Override
public View getChildView(int groupPosition, final int childPosition,
boolean isLastChild, View convertView, ViewGroup parent) {
final String childText = (String) getChild(groupPosition, childPosition);
if (convertView == null) {
LayoutInflater infalInflater = (LayoutInflater) this._context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = infalInflater.inflate(R.layout.list_item, null);
}
TextView txtListChild = (TextView) convertView
.findViewById(R.id.lblListItem);
txtListChild.setText(childText);
return convertView;
}
@Override
public int getChildrenCount(int groupPosition) {
return 1;
}
@Override
public Object getGroup(int groupPosition) {
return this._listDataHeader.get(groupPosition);
}
@Override
public int getGroupCount() {
return this._listDataHeader.size();
}
@Override
public long getGroupId(int groupPosition) {
return groupPosition;
}
@Override
public View getGroupView(int groupPosition, boolean isExpanded,
View convertView, ViewGroup parent) {
String headerTitle = (String) getGroup(groupPosition);
if (convertView == null) {
LayoutInflater infalInflater = (LayoutInflater) this._context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = infalInflater.inflate(R.layout.spinner, null);
}
TextView lblListHeader = (TextView) convertView
.findViewById(R.id.lblListHeader);
lblListHeader.setTypeface(Controller.getInstance().getTypeface());
lblListHeader.setText(headerTitle);
//I can' do this in this place
//ImageView iv = (ImageView)convertView.findViewById(R.id.exc);
//iv.setImageResource(R.drawable.excl);
return convertView;
}
@Override
public boolean hasStableIds() {
return false;
}
@Override
public boolean isChildSelectable(int groupPosition, int childPosition) {
return true;
}
}
And Activity:
public class ExpertZone extends Activity{
String err;
Context context;
ExpandableListAdapter listAdapter;
ExpandableListView expListView;
List<String> listDataHeader;
HashMap<String, String> listDataChild;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.expert_zone);
context=this;
// get the listview
expListView = (ExpandableListView) findViewById(R.id.expListView);
// preparing list data
prepareListData();
}
/*
* Preparing the list data
*/
private void prepareListData() {
listDataHeader = new ArrayList<String>();
listDataChild = new HashMap<String, String>();
DBexpertTask dbTask = new DBexpertTask(getString(R.string.expertServlet)) {
@Override
protected void onPostExecute(JSONObject obj) {
JSONArray jArray = new JSONArray();
try {
JSONArray jsonObject = obj.getJSONArray(getString(R.string.data));
for (int i = 0; i < jsonObject.length(); i++) {
JSONObject object = jsonObject.getJSONObject(i);
err = object.getString(getString(R.string.err));
if(err.equals(getString(R.string.no))) {
jArray = object.getJSONArray(getString(R.string.data));
for (int j = 0; j < jArray.length(); j++) {
JSONObject values = jArray.getJSONObject(j);
listDataHeader.add(String.valueOf(values.get(getString(R.string.who)).toString()));
listDataChild.put(String.valueOf(values.get(getString(R.string.who)).toString()), String.valueOf(values.get(getString(R.string.what)).toString()));
}
}
}
} catch (JSONException e) {
e.printStackTrace();
}
listAdapter = new ExpandableListAdapter(context, listDataHeader, listDataChild);
// setting list adapter
expListView.setAdapter(listAdapter);
for(int j=0; j<expListView.getCount(); j++){
expListView.getLastVisiblePosition();
expListView.getFirstVisiblePosition();
View v = expListView.getChildAt(j).findViewById(R.id.expListView);
ImageView iv = (ImageView) v.findViewById(R.id.exc);
iv.setImageResource(R.drawable.excl);
}
}
};
dbTask.execute();
}
}
my xml - cell layout
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:weightSum="6">
<TextView
android:id="@+id/lblListHeader"
android:paddingLeft="?android:attr/expandableListPreferredItemPaddingLeft"
android:gravity="center_vertical|center_horizontal"
android:layout_weight="5"
android:layout_width="0dp"
android:layout_height="60dp"
android:textSize="18dp" />
<ImageView
android:id="@+id/exc"
android:layout_weight="1"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:gravity="center_vertical|center_horizontal"
android:layout_gravity="center_vertical" />
</LinearLayout>
and expert_zone.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:layout_alignParentBottom="true"
>
<ExpandableListView
android:id="@+id/expListView"
android:layout_height="match_parent"
android:layout_width="match_parent"/>
</LinearLayout>
How can I dynamically change image icon in this adapter? Suggestions are highly appreciated.
