set width of linear layout in horizontal scroll view

Question

I have the following linear layout,and I am setting it as a child to HorizontalScrollView

File menu.xml

 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/menu"
android:orientation="vertical" android:background="#2f4f4f" android:layout_width="wrap_content" android:layout_height="fill_parent">

  <ListView android:id="@+id/list" android:layout_width="fill_parent" android:layout_height="wrap_content"
    android:background="#2f4f4f" android:cacheColorHint="#2f4f4f" android:scrollbars="none">
  </ListView>
</LinearLayout>

File : scrollview.xml

 <?xml version="1.0" encoding="utf-8"?>
 <HorizontalScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent" android:layout_height="fill_parent" android:background="#00ffffff" android:padding="0px"
android:layout_margin="0px" android:fadingEdge="none" android:fadingEdgeLength="0px" android:scrollbars="none">
    <LinearLayout android:id="@+id/top" android:layout_height="fill_parent" android:layout_width="fill_parent"
    android:orientation="horizontal" android:background="#ffffffff" android:padding="0px" android:layout_margin="0px">
    </LinearLayout>
</HorizontalScrollView>

I am trying to set the width of the linear layout programatically but I am getting ClassCastException.(LinearLayout$LayputParams can't be cast to FrameLayout$LayputParams)

LayoutInflater inflater = LayoutInflater.from(this);
scrollView = inflater.inflate(R.layout.scrollview_xml, null);
setContentView(scrollView);
View menu = inflater.inflate(R.layout.menu_xml, null);
scrollView.addView(menu);
scrollView.getChildAt(0).setLayoutParams(new ViewGroup.LayoutParams(100,100));

How to solve this ?

Answer 1

1. since the scrollView extends a FrameLayout , you need to set the layoutParams of its children to have the FrameLayout's layoutParams .

2. since it says you have an exception because you set the layoutParams for the wrong layout , use the correct ones :

   scrollView.getChildAt(0).setLayoutParams(new FrameLayout.LayoutParams(100,100));

3. in general , if you have any doubt about the type of the layout , use :

   scrollView.getChildAt(0).setLayoutParams(new ViewGroup.LayoutParams(100,100));