Expandable listview inside scrollview

This solution worked for me, when i used custom layout inside navigation view having scroll view with LinearLayout which has Expandable listview.

<android.support.design.widget.NavigationView
        android:id="@+id/nav_view"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        app:headerLayout="@layout/nav_header">
    <ScrollView
            android:fillViewport="true"
            android:layout_marginTop="130dp"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">
            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:orientation="vertical">

                <LinearLayout
                    android:id="@+id/homeLayout"
                    android:clickable="true"
                    android:gravity="center_vertical"
                    android:background="@drawable/layout_click_effect"
                    android:layout_width="match_parent"
                    android:layout_height="45dp">

                    <ImageView
                        android:id="@+id/homeIv"
                        android:layout_width="45dp"
                        android:layout_height="wrap_content"
                        android:src="@mipmap/ic_home_black_24dp" />

                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="Home" />
                </LinearLayout>
                <View
                    android:background="@android:color/darker_gray"
                    android:layout_width="match_parent"
                    android:layout_height="1dp"/>

                <ExpandableListView
                    android:id="@+id/topCatgExpLv"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_gravity="start"
                    android:groupIndicator="@null"
                    android:dividerHeight="1dp" />
        </ScrollView>


    </android.support.design.widget.NavigationView>

In your onCreate

mListView = (ExpandableListView) findViewById(R.id.activity_expandable_list_view);
    MyExpandableListAdapter adapter = new MyExpandableListAdapter(this,
            mGroups);
    mListView.setAdapter(adapter);
    mListView.setOnGroupClickListener(new ExpandableListView.OnGroupClickListener() {

        @Override
        public boolean onGroupClick(ExpandableListView parent, View v,
                                    int groupPosition, long id) {
            setListViewHeight(parent, groupPosition);
            return false;
        }
    });

private void setListViewHeight(ExpandableListView listView, int group) {
    ExpandableListAdapter listAdapter = (ExpandableListAdapter) listView.getExpandableListAdapter();
    int totalHeight = 0;
    int desiredWidth = View.MeasureSpec.makeMeasureSpec(listView.getWidth(),
            View.MeasureSpec.EXACTLY);
    for (int i = 0; i < listAdapter.getGroupCount(); i++) {
        View groupItem = listAdapter.getGroupView(i, false, null, listView);
        groupItem.measure(desiredWidth, View.MeasureSpec.UNSPECIFIED);

        totalHeight += groupItem.getMeasuredHeight();

        if (((listView.isGroupExpanded(i)) && (i != group))
                || ((!listView.isGroupExpanded(i)) && (i == group))) {
            for (int j = 0; j < listAdapter.getChildrenCount(i); j++) {
                View listItem = listAdapter.getChildView(i, j, false, null,
                        listView);
                listItem.measure(desiredWidth, View.MeasureSpec.UNSPECIFIED);

                totalHeight += listItem.getMeasuredHeight();

            }
            //Add Divider Height
            totalHeight += listView.getDividerHeight() * (listAdapter.getChildrenCount(i) - 1);
        }
    }
    //Add Divider Height
    totalHeight += listView.getDividerHeight() * (listAdapter.getGroupCount() - 1);

    ViewGroup.LayoutParams params = listView.getLayoutParams();
    int height = totalHeight
            + (listView.getDividerHeight() * (listAdapter.getGroupCount() - 1));
    if (height < 10)
        height = 200;
    params.height = height;
    listView.setLayoutParams(params);
    listView.requestLayout();
}

you can do this very simple . set your height of scroll view to wrap_content. set your height of root view inside scroll view as wrap_content (such as linear layout) and set your expandable list view to wrap_content. after that set OnGroupExpandListener and OnGroupCollapseListener for your expandable list view and set height for that as long as child of expandable list view. like this code : your layout :

<ScrollView
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/scrollViewDrawer"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:fillViewport="true"
>
<LinearLayout
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    android:background="@color/mainGray"
    >
 <ExpandableListView
    android:id="@+id/expandableListCategory"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
                />
 </LinearLayout>
 </ScrollView>

and this is your fragment: (or in your activity)

public class DrawerFragment extends Fragment implements, OnGroupExpandListener, OnGroupCollapseListener{
ScrollView scrollView;
ExpandableListView expListView;

public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
view rootView = inflater.inflate(R.layout.fragment_layout, container, false);
scrollView = (ScrollView) rootView.findViewById(R.id.scrollViewDrawer);
expListView = (ExpandableListView) rootView.findViewById(R.id.expandableListCategory);
....
}
@Override
public void onGroupExpand(int groupPosition) {
    LinearLayout.LayoutParams param = (LinearLayout.LayoutParams) expListView.getLayoutParams();
    param.height = (childCount * expListView.getHeight());
    expListView.setLayoutParams(param);
    expListView.refreshDrawableState();
    scrollView.refreshDrawableState();
}

@Override
public void onGroupCollapse(int groupPosition) {
    LinearLayout.LayoutParams param = (LinearLayout.LayoutParams) expListView.getLayoutParams();
    param.height = LinearLayout.LayoutParams.WRAP_CONTENT;
    expListView.setLayoutParams(param);
    expListView.refreshDrawableState();
    scrollView.refreshDrawableState();
}