Inflating Layout XML to custom LinearLayout creates redundant LinearLayout view

Question

I'm creating a custom LinearLayout component. It's designed to mimic some functionality of a ListView, for use in a ScrollView, since I can't/shouldn't use a ListView inside a ScrollView. Let's call it CustomListView. Furthermore, I'm creating another custom LinearLayout to represent each item in this pseudo-listview, let's call it NewItemView.

Anyway, when initialising NewItemView, I'm setting it up by inflating a layout XML. The layout XML declares a LinearLayout as its root view, and is not dissimilar to layouts like simple_list_item_multiple_choice.xml.

Overall, what happens is that the main activity has a CustomListView. We call addItem(Item item) on CustomListView to add a new item to the list, which in reality, creates a new NewItemView, and populates it with data from the Item class.

I'm inflating in newListItem.initListItem(Context context) as so:

 ((Activity)getContext())
            .getLayoutInflater()
            .inflate(R.layout.list_item, this, true);

This actually works! However, the issue I have is that on inspection with Monitor, there's a redundant LinearLayout just sitting around each item in the list. My understanding is that this is generally a bad idea. There's the LinearLayout for CustomListView, then for each item, there's a LinearLayout, with just one child; a LinearLayout! That last one contains the actual children.

I expect that it has something to do with the fact that I'm creating a custom component based off LinearLayout, and then inflating a layout with a LinearLayout at it's root.

Answer 1

Yes, this is what the merge tag is for. Simply replace your root LinearLayout tag with merge, and that should do what you need.

See this blog post.