We are all familiar with the findVIewById() method but it is a costly operation for applications. Each and every time we try to do findVIewById() that particular view is being searched in the view hierarchy during runtime which is a time consuming process and it can slow the application for the user.

To fix it we can go with Data Binding. Data Binding allows us to connect to a layout to an activity or fragment at compile time. The compiler generates a helper class called a binding class when an activity/fragment is created and then by using that binding class object we can access views easily and perform operations on it.

Dependencies:

To enable data binding in our project add below lines in our app level gradle

android {
    ...
    buildFeatures {
        dataBinding true
    }
}

How to implement:

Use better pointers

1. Surround the layout xml code in <layout></layout> and add the namespace declarations to the tag.

Ex:
<layout 
xmlns:android="http://schemas.android.com/apk/res/android"
   		xmlns:app="http://schemas.android.com/apk/res-auto">
		<LinearLayout
   			android:layout_width="match_parent"
   			android:layout_height="match_parent"
   			android:orientation="vertical">
		<TextView
   			android:id="@+id/score_text"
   			android:layout_width="wrap_content"
   			android:layout_height="wrap_content"/>

		</LinearLayout>	    
</layout>

2. Get a data binding object in our activity/fragment by calling

DataBindingUtil.setContentView() for activity DataBindingUtil.inflate() for fragment.

val dataBindingObject  = DataBindingUtil.setContentView<ActivityMainBinding>(this, R.layout.activity_main)

Note: Let’s say the name of the activity is MainActivity then the binding class for the activity will be ActivityMainBinding.

3. Now by using the binding object we can call the views directly.

Ex: 
dataBindingObject.scoreText = View.VISIBLE

class MyScoreDetailsFragment : Fragment()
{
override fun onCreateView(inflater: LayoutInflater,   container: ViewGroup?, savedInstanceState: Bundle?): View?
{
		val binding: MyScoreDetailsFragment = DataBindingUtil.inflate(inflater, R.layout.myscoredetails_fragment, container, false)
binding.scoreText.text = "score"
return binding.root
}
}

Basically with data binding enabled the compiler creates a reference to all views in a <layout></layout> that have an id and gathers them in a binding object and then we just use the object to perform operations on them.