Should I pass context to adapter?

Should I pass context to adapter?

Passing Context to the adapter is completely unnecessary, since RecyclerView you can access it from inside the class. Obtaining Context at ViewHolder level means that you do it every time you bind or create a ViewHolder .

What does a RecyclerView adapter do?

RecyclerView. Adapter base class for presenting List data in a RecyclerView , including computing diffs between Lists on a background thread. Adapters provide a binding from an app-specific data set to views that are displayed within a RecyclerView .

How do I get the activity context on my adapter?

4 Answers. If you have a custom adapter, change the constructor to require Context as a parameter. Then, create an Instance variable to store the context via the constructor. And now you can use the variable mContext from anywhere in your adapter.

When onViewRecycled is called?

The onViewRecycled is not for “freeing resources”. It is called when the adapter view created is recycled or re-used.

How does kotlin initialize context?

First you should use requireContext() instead of context() for avoid from memory leak. For show Toast for every time, you can initialize handler in setUserVisibleHint , then after some delay run your code!

What is the adapter responsible for?

An Adapter object acts as a bridge between an AdapterView and the underlying data for that view. The Adapter provides access to the data items. The Adapter is also responsible for making a View for each item in the data set.

What happens when notifyDataSetChanged is called?

In the code, channelListAdapter. notifyDataSetChanged() was called. all Adapter subclasses Adapter reference must call notifyDataSetChanged() when their underlying data has changed, to let the observing view (ListView and such) know that it should refresh itself because the data changed / there is new data.

Can a fragment exist without UI?

A fragment is not required to be a part of the Activity layout ; you may also use a fragment without its own UI as an invisible worker for the Activity but it needs to be attached to an Activity in order to appear on the screen. Android app must have an Activity or FragmentActivity that handles the fragment.

What does context mean in Kotlin?

A Context provides access to information about the application state. It provides Activities, Fragments, and Services access to resource files, images, themes/styles, and external directory locations.

How can I get RecyclerView adapter?

How to use getAdapter method in androidx.recyclerview.widget.RecyclerView

1. View view;view.findViewById(id)
2. View view;(RecyclerView) view.findViewById(id)
3. LayoutInflater layoutInflater;ViewGroup root;(RecyclerView) layoutInflater.inflate(resource, root, false)

How does kotlin pass context from fragment?

To get the context in a fragmented use getActivity(), which renders the activity associated with a fragment. The activity is a context (since Activity continues Context). thiscontext = container. getContext();

How does a recyclerview work with an adapter?

Together, this relationship looks like this: Meaning the RecyclerView needs it’s two root components set – the LayoutManager and Adapter. The adapter then uses the ViewHolder and appropriate data to manipulate the RecyclerView, and the ViewHolder uses an underlying Layout Resource to inflate the view.

How are view holders created in recyclerview Android?

The view holder objects are managed by an adapter, which you create by extending RecyclerView.Adapter. The adapter creates view holders as needed. The adapter also binds the view holders to their data. It does this by assigning the view holder to a position, and calling the adapter’s onBindViewHolder() method.

When is the listadapter called by the recyclerview?

Called by RecyclerView when it stops observing this Adapter. Called by the RecyclerView if a ViewHolder created by this Adapter cannot be recycled due to its transient state. Called when a view created by this adapter has been attached to a window.

What is recyclerview and what does it do?

RecyclerView The RecyclerView is a newer Android ViewGroup object meant to render any adapter-based View. It’s similar to a ListView, but with many updated features, including the ability to implement both horizontal and vertical lists.