Comment définir aucun indicateur pour le groupe ayant zéro enfant dans Expandable ListView?

Question

Je veux définir aucun indicateur pour les groupes ayant zéro enfant. J'ai utilisé la liste extensible. Ceci est la capture d'écran Initial layout. Initialement, les groupes avec zéro enfant n'ont aucun indicateur. Mais dès que j'élargis mon groupe avec un nombre défini des enfants alors les groupes sans enfant commencent également à montrer l'indicateur.

MainActivity.xml

<?xml version="1.0" encoding="utf-8"?> 
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:app="http://schemas.android.com/apk/res-auto" 
    xmlns:ads="http://schemas.android.com/apk/res-auto" 
    xmlns:tools="http://schemas.android.com/tools" 
    android:id="@+id/drawer_layout" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:fitsSystemWindows="true" 
    tools:openDrawer="start"> 


    <include 
     layout="@layout/app_bar_main" 
     android:layout_width="match_parent" 
     android:layout_height="match_parent" /> 


    <android.support.design.widget.NavigationView 
     android:id="@+id/nav_view" 
     android:layout_width="wrap_content" 
     android:layout_height="match_parent" 
     android:layout_gravity="start" 
     android:fitsSystemWindows="true" 
     app:headerLayout="@layout/nav_header_main" 
     android:clickable="true"> 

     <LinearLayout 
      android:layout_width="match_parent" 
      android:layout_height="match_parent" 
      android:orientation="vertical"> 

    <ExpandableListView 
     android:id="@+id/exp_list" 
     android:layout_width="match_parent" 
     android:layout_height="match_parent" 
     android:layout_marginTop="160dp" 
     android:indicatorRight="?android:attr/expandableListPreferredItemIndicatorRight" 
     android:background="@android:color/white" 
     android:footerDividersEnabled="true" 
     android:groupIndicator="@null"> 
    </ExpandableListView> 

      <!--<ListView--> 
       <!--android:background="@android:color/white"--> 
       <!--android:id="@+id/menuList"--> 
       <!--android:layout_width="match_parent"--> 
       <!--android:layout_height="match_parent"--> 
       <!--android:layout_marginTop="10dp" />--> 
     </LinearLayout> 
    </android.support.design.widget.NavigationView> 

</android.support.v4.widget.DrawerLayout> 

Listheader.xml

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    android:orientation="vertical" android:layout_width="match_parent" 
    android:layout_height="match_parent"> 

    <LinearLayout 
     android:layout_width="match_parent" 
     android:layout_height="match_parent" 
     android:layout_marginLeft="5dp" 
     android:orientation="horizontal"> 

     <ImageView 
      android:id="@+id/iconimage" 
      android:layout_width="40dp" 
      android:layout_height="40dp" 
      android:padding="10dp"/> 

     <TextView 
      android:id="@+id/submenu" 
      android:layout_width="match_parent" 
      android:layout_height="wrap_content" 
      android:padding="10dp" 
      android:textColor="#000000" 
      android:textSize="16sp" 
      android:gravity="center_vertical" /> 


    </LinearLayout> 

</LinearLayout> 

ExpandableListAdapter.java

package com.global.market; 

import android.content.Context; 
import android.util.Log; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.ViewGroup; 
import android.widget.BaseExpandableListAdapter; 
import android.widget.ExpandableListView; 
import android.widget.ImageView; 
import android.widget.TextView; 

import java.util.HashMap; 
import java.util.List; 

/** 
* Created by Samarth on 17-Jul-16. 
*/ 
public class ExpandableListAdapter extends BaseExpandableListAdapter { 

    private Context mContext; 
    private List<ExpandedMenuModel> mListDataHeader; // header titles 

    // child data in format of header title, child title 
    private HashMap<ExpandedMenuModel, List<String>> mListDataChild; 
    ExpandableListView expandList; 

    public ExpandableListAdapter(Context context, List<ExpandedMenuModel> listDataHeader, 
           HashMap<ExpandedMenuModel, List<String>> listChildData, ExpandableListView mView) { 
     this.mContext = context; 
     this.mListDataHeader = listDataHeader; 
     this.mListDataChild = listChildData; 
     this.expandList = mView; 
    } 

    @Override 
    public int getGroupCount() { 
     int i = mListDataHeader.size(); 
     Log.d("GROUPCOUNT", String.valueOf(i)); 
     return this.mListDataHeader.size(); 
    } 

    @Override 
    public int getChildrenCount(int groupPosition) { 
     int childCount = 0; 
     if (groupPosition<2) { 
      childCount = this.mListDataChild.get(this.mListDataHeader.get(groupPosition)) 
        .size(); 
     } 
     return childCount; 
    } 

    @Override 
    public Object getGroup(int groupPosition) { 
     Log.d("Group",groupPosition+""); 
     return this.mListDataHeader.get(groupPosition); 
    } 

    @Override 
    public Object getChild(int groupPosition, int childPosition) { 
//  Log.d("CHILD", mListDataChild.get(this.mListDataHeader.get(groupPosition)) 
//    .get(childPosition).toString()); 
     return this.mListDataChild.get(this.mListDataHeader.get(groupPosition)) 
       .get(childPosition); 
    } 

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

    @Override 
    public long getChildId(int groupPosition, int childPosition) { 
     return childPosition; 
    } 

    @Override 
    public boolean hasStableIds() { 
     return false; 
    } 

    @Override 
    public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) { 
     ExpandedMenuModel headerTitle = (ExpandedMenuModel) getGroup(groupPosition); 
     if (convertView == null) { 
      LayoutInflater infalInflater = (LayoutInflater) this.mContext 
        .getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
      convertView = infalInflater.inflate(R.layout.listheader, null); 
     } 
     TextView lblListHeader = (TextView) convertView 
       .findViewById(R.id.submenu); 
     ImageView headerIcon = (ImageView) convertView.findViewById(R.id.iconimage); 
     // lblListHeader.setTypeface(null, Typeface.BOLD); 
     lblListHeader.setText(headerTitle.getIconName()); 
     headerIcon.setImageResource(headerTitle.getIconImg()); 

     if (isExpanded && getChildrenCount(groupPosition)>0) { 

      lblListHeader.setCompoundDrawablesWithIntrinsicBounds(0, 0, 
        R.drawable.collapse, 0); 
     } 
     else if(getChildrenCount(groupPosition)>0){ 
      // If group is not expanded then change the text back into normal 
      // and change the icon 

      lblListHeader.setCompoundDrawablesWithIntrinsicBounds(0, 0, 
        R.drawable.expand, 0); 
     } 
     return convertView; 
    } 

    @Override 
    public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) { 
     final String childText = (String) getChild(groupPosition, childPosition); 

     if (convertView == null) { 
      LayoutInflater infalInflater = (LayoutInflater) this.mContext 
        .getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
      convertView = infalInflater.inflate(R.layout.list_submenu, null); 
     } 

     TextView txtListChild = (TextView) convertView 
       .findViewById(R.id.submenu); 

     txtListChild.setText(childText); 

     return convertView; 
    } 

    @Override 
    public boolean isChildSelectable(int groupPosition, int childPosition) { 
     return true; 
    } 


} 

Answer 1

Je pense que vous ajoutez une icône dans votre GroupView. Puis, au cours getGroupView(), vous vérifiez combien de vue des enfants de ce groupe ont et décider d'afficher ou non l'icône « vide »

Group Voir la mise en page:

<LinearLayout> 
    <LinearLayout 
     ...> 
     <ImageView 
      .../> 
     <TextView 
      ... /> 

     <ImageView> 
     <!-- IMAGEVIEW ICON TO SHOW THIS GROUP IS EMPTY --> 
     android:id="@+id/empty_group_icon" 
     android:visibility="invisible" 
     </ImageView> 

     </LinearLayout> 
</LinearLayout> 

Et dans votre getGroupView()

@Override 
public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) { 
    ... 
    if(getChildrenCount(groupPosition) > 0) 
     convertView.findViewById(R.id.empty_group_icon).setVisibility(View.INVISIBLE); 
    else 
     convertView.findViewById(R.id.empty_group_icon).setVisibility(View.VISIBLE); 

    return convertView; 
}