Я пытаюсь реализовать ExpandableListview, расширяя ExpandableListAdapter во фрагменте.Нет проблем при отображении фрагмента с родительскими узлами.как только я нажимаю на родительское приложение, которое останавливается и выбрасывает исключение, показывающее дочерний элемент путем расширения
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.ekatechhp.pkmapplication, PID: 29388
java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference
at com.example.ekatechhp.pkmapplication.holder.ExpandableListAdapter.getChildView(ExpandableListAdapter.java:50)
at android.widget.ExpandableListConnector.getView(ExpandableListConnector.java:451)
at android.widget.AbsListView.obtainView(AbsListView.java:2346)
at android.widget.ListView.makeAndAddView(ListView.java:1876)
at android.widget.ListView.fillDown(ListView.java:702)
at android.widget.ListView.fillSpecific(ListView.java:1367)
at android.widget.ListView.layoutChildren(ListView.java:1663)
at android.widget.AbsListView.onLayout(AbsListView.java:2148)
at android.view.View.layout(View.java:16651)
at android.view.ViewGroup.layout(ViewGroup.java:5440)
at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1743)
at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1586)
at android.widget.LinearLayout.onLayout(LinearLayout.java:1495)
at android.view.View.layout(View.java:16651)
at android.view.ViewGroup.layout(ViewGroup.java:5440)
at android.support.v4.view.ViewPager.onLayout(ViewPager.java:1775)
at android.view.View.layout(View.java:16651)
at android.view.ViewGroup.layout(ViewGroup.java:5440)
at android.support.design.widget.HeaderScrollingViewBehavior.layoutChild(HeaderScrollingViewBehavior.java:142)
at android.support.design.widget.ViewOffsetBehavior.onLayoutChild(ViewOffsetBehavior.java:41)
at android.support.design.widget.AppBarLayout$ScrollingViewBehavior.onLayoutChild(AppBarLayout.java:1556)
at android.support.design.widget.CoordinatorLayout.onLayout(CoordinatorLayout.java:888)
at android.view.View.layout(View.java:16651)
at android.view.ViewGroup.layout(ViewGroup.java:5440)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:336)
at android.widget.FrameLayout.onLayout(FrameLayout.java:273)
at android.view.View.layout(View.java:16651)
at android.view.ViewGroup.layout(ViewGroup.java:5440)
at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1743)
at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1586)
at android.widget.LinearLayout.onLayout(LinearLayout.java:1495)
at android.view.View.layout(View.java:16651)
at android.view.ViewGroup.layout(ViewGroup.java:5440)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:336)
at android.widget.FrameLayout.onLayout(FrameLayout.java:273)
at android.view.View.layout(View.java:16651)
at android.view.ViewGroup.layout(ViewGroup.java:5440)
at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1743)
at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1586)
at android.widget.LinearLayout.onLayout(LinearLayout.java:1495)
at android.view.View.layout(View.java:16651)
at android.view.ViewGroup.layout(ViewGroup.java:5440)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:336)
at android.widget.FrameLayout.onLayout(FrameLayout.java:273)
at com.android.internal.policy.PhoneWindow$DecorView.onLayout(PhoneWindow.java:2678)
at android.view.View.layout(View.java:16651)
at android.view.ViewGroup.layout(ViewGroup.java:5440)
at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2183)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1943)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1119)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6060)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:858)
at android.view.Choreographer.doCallbacks(Choreographer.java:670)
at android.view.Choreographer.doFrame(Choreographer.java:606)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:844)
at android.os.Handler.handleCallback(Handler.java:746)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.ja
, я не могу понять, почему оно вызывает исключение.В действии работает, получил фрагмент во фрагменте
ExpandableListAdapter.java
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, List<String>> _listDataChild;
public ExpandableListAdapter(Context context, List<String> listDataHeader,
HashMap<String, List<String>> listDataChild) {
this._context = context;
this._listDataHeader = listDataHeader;
this._listDataChild = listDataChild;
}
@Override
public Object getChild(int groupPosition, int childPosititon) {
return this._listDataChild.get(this._listDataHeader.get(groupPosition))
.get(childPosititon);
}
@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 this._listDataChild.get(this._listDataHeader.get(groupPosition))
.size();
}
@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.my_know_list_group, null);
}
TextView lblListHeader = (TextView) convertView
.findViewById(R.id.lblListHeader);
lblListHeader.setTypeface(null, Typeface.BOLD);
lblListHeader.setText(headerTitle);
return convertView;
}
@Override
public boolean hasStableIds() {
return false;
}
@Override
public boolean isChildSelectable(int groupPosition, int childPosition) {
return true;
}
}