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Android Android Lists and Adapters (2015) Custom ListViews getView() and the ViewHolder Pattern

CD Lim
CD Lim
4,782 Points
Posted by CD Lim
CD Lim
4,782 Points

what is View Group Root?

Hi I would just like to know what is a View Group Root. Ben stated that in creating our inflater 

convertView = LayoutInflater.from(mContext).inflate(R.layout.daily_list_item, null);

the view group root is set to null and Ben said it is not needed. However, may I ask what is it?

1 Answer

Ben Deitch
STAFF
Ben Deitch
Treehouse Teacher
Ben Deitch
Ben Deitch
Treehouse Teacher

The second parameter is an optional view to be the parent of the generated hierarchy. http://developer.android.com/reference/android/view/LayoutInflater.html#inflate(int, android.view.ViewGroup)

So if we specified a ViewGroup for the second parameter, R.layout.daily_list_item would be added as a child to the ViewGroup that we specified. If we leave the second parameter as null, R.layout.daily_list_item would be added as a child to the root ViewGroup which is the top element in the layout.

In this image, the RelativeLayout at top is the root ViewGroup.

CD Lim
CD Lim
4,782 Points
CD Lim
CD Lim
4,782 Points

wow thanks for the crystal clear explanation...