Android Question
How recycler view works internally?

Question

Android Question

How recycler view works internally?

Accepted Answer

RecyclerView is a UI component which allows us to create a scrolling list. It is basically a new ViewGroup used to render any adapter-based view in horizontal/vertical /grid or staggered grid manner using the Viewholder pattern.

Working : So, let’s say when we are scrolling the list which has 50 items in the collection and we show only 5 items at once in the list. Here, item 1 to item 5 is the ones that are visible on the screen. item x is the one that will be loaded next on the screen when we scroll up. All the items here have their own instance of ViewHolder and the ViewHolder here is helpful for caching the specific item’s view. This is how recycling of views happens in recyclerView which is one of the main reasons for the better improvement of recyclerView. In this process, the views of the item are reused to draw new items on the screen.
Similarly, if we have multiple view types, let’s say ViewType1 and ViewType2 then we would have two different collections of scrapped view of type ViewType1 and ViewType2.And while recycling the views, the ViewType1 view will be allocated to only views of ViewType1 and ViewType2 views will be allocated to ViewType2 views.

Accepted Answer

View Recycling and Reuse :

Core Idea: Minimize the creation of new views by reusing existing ones.

When a view scrolls out of the visible area, it is detached and added to a recycled view pool.
When a new view is required, RecyclerView checks the pool:
-If a suitable recycled view exists, it reuses it.
-Otherwise, it creates a new view using the adapter.

This process avoids frequent calls to findViewById or inflating layouts, significantly improving performance.

Accepted Answer

RecyclerView works by efficiently managing and recycling views as they come in and out of view, which reduces memory consumption and improves scrolling performance.
It uses a ViewHolder pattern to avoid creating new views unnecessarily, a LayoutManager to arrange items in various layouts, and a RecycledViewPool to pool and reuse views.
The overall architecture makes it much more efficient and flexible compared to older components like ListView or GridView, especially when dealing with large datasets.

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