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how i can fix databinding error while inflate view

When I normally I app run after building android studio throws this error.
at com.shayan.test.databinding.ActivityMainBinding.inflate(ActivityMainBinding.java:113)
E/AndroidRuntime: at com.shayan.test.MainActivity.onCreate(MainActivity.kt:14)
I think I forget something to do calling method or something
package com.shayan.test
package com.shayan.test
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import com.shayan.test.databinding.ActivityMainBinding
class MainActivity : AppCompatActivity() {
lateinit var binding: ActivityMainBinding
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
binding = ActivityMainBinding.inflate(LayoutInflater.from(this))
(binding.root)
}
}

your using viewbinding.. setContentView is missing. and
binding = ActivityMainBinding.inflate(LayoutInflater.from(this))
change to
binding = ActivityMainBinding.inflate(layoutInflater)
Full code for example
class MainActivity : AppCompatActivity() {
private lateinit var binding: ActivityMainBinding
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
binding = ActivityMainBinding.inflate(layoutInflater)
setContentView(binding.root)

Try this methods :
//Try to add in build.gradle (Module:app)
buildFeatures {
viewBinding true
}
2:
Build -> Clean Project
Build -> Rebuild Project
If this method does not help you then It's not about the Gradle file. It is about the XML file.

Not able to import image id

enter image description here
Glide.with(this).load(url).into(imageView)

You can try with findViewById:
Glide.with(this).load(url).into(findViewById(R.id.imageView))
However, the best approach would be using viewBinding:
class MainActivity : AppCompatActivity() {
private lateinit var binding: ActivityMainBinding
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
binding = ActivityMainBinding.inflate(layoutInflater)
setContentView(binding.root)
...
Glide.with(this).load(url).into(binding.imageView)
}
}
In this case, don't forget to enable viewBinding in your app-level build.gradle file, by adding:
android {
...
buildFeatures {
viewBinding = true
}
}
For more on viewBinding check here

Kotlin / Migration to View Binding

I was following YT video to make Quiz App, but in the end I got this error with binding:
The 'kotlin-android-extensions' Gradle plugin is deprecated.
Please use this migration guide
(https://goo.gle/kotlin-android-extensions-deprecation) to start working with View Binding (https://developer.android.com/topic/libraries/view-binding) and the 'kotlin-parcelize' plugin.
But when I add binding for instance to tv_name.text, i do get error that text is expecting Variable and everything the same with other binding parts.
Libraries part
import android.content.Intent
import android.os.Bundle
import android.view.View
import androidx.appcompat.app.AppCompatActivity
import androidx.core.view.WindowCompat
import com.example.quizapp.databinding.ActivityResultBinding
Code part
class ResultActivity : AppCompatActivity() {
private val binding by viewBinding(FragmentResultActivity::bind)
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_result)
// Hide the status bar.
//window.decorView.systemUiVisibility = View.SYSTEM_UI_FLAG_FULLSCREEN
val userName = intent.getStringExtra(Constants.USER_NAME)
binding.tv_name.text = userName
val totalQuestions = intent.getIntExtra(Constants.TOTAL_QUESTIONS, 0)
val correctAnswers = intent.getIntExtra(Constants.CORRECT_ANSWERS, 0)
binding.tv_score.text = "Your Score is $correctAnswers out of $totalQuestions."
binding.btn_finish.setOnClickListener {
startActivity(Intent(this#ResultActivity, MainActivity::class.java))
}
}
}

You need to initialize the binding variable properly. Please use the below code:
class ResultActivity : AppCompatActivity() {
private lateinit var binding: ActivityResultBinding
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
binding = ActivityResultBinding.inflate(layoutInflater)
setContentView(binding.root)
// Hide the status bar.
//window.decorView.systemUiVisibility = View.SYSTEM_UI_FLAG_FULLSCREEN
val userName = intent.getStringExtra(Constants.USER_NAME)
binding.tv_name.text = userName
val totalQuestions = intent.getIntExtra(Constants.TOTAL_QUESTIONS, 0)
val correctAnswers = intent.getIntExtra(Constants.CORRECT_ANSWERS, 0)
binding.tv_score.text = "Your Score is $correctAnswers out of $totalQuestions."
binding.btn_finish.setOnClickListener {
startActivity(Intent(this#ResultActivity, MainActivity::class.java))
}
}
}
Since I do not have your resources with me available, I think you might have to change the naming of ActivityResultBinding. However, I am pretty sure this is it.
Happy Coding! :)

First you need to let android know that you are using view binding. so go to "Gradle Scripts" folder and open app level build.gradle(Module:nameOfProject) file and inside android property add this:
android {
// ------ VIEW BINDING SETTING ------
// this creates the binding object
buildFeatures{
viewBinding true
}
// after set up, click on "Sync Now"
}
then in MainActivity.kt:
class MainActivity : AppCompatActivity() {
// Initialize binding object. if ActivityMainBinding is not ready in menu click "Build/Make project"
private lateinit var binding:ActivityMainBinding
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
// view Bindig
// binding default layout inflater
binding= ActivityResultBinding.inflate(layoutInflater)
// inflate the root views which is Linear Layout, we access with .root
setContentView(binding.root)
// Set click listeners
....
}

Why does Kotlin Activity have a problem finding Buttons?

Attempting to update an older Android game project to use view binding. Android Studio version 4.1.3. I am thinking my problem has to do with the naming of my binding class.
the xml file is called activity_correct_guess.xml and I am using what I think is the name that gets generated by the view binding: ActivityCorrectGuessBinding. Appreciate and ideas!
The build errors:
Unresolved reference: ActivityCorrectGuessBinding
Unresolved reference: binding
Unresolved reference: binding
In the Gradle build module I have the following:
android {
compileSdkVersion 30
buildToolsVersion "30.0.0"
buildFeatures {
viewBinding = true
}
layout file: activity_correct_guess.xml
<Button
android:id="#+id/btnPlayAgain"
android:layout_width="wrap_content"
..... />
Activity file: CorrectGuessActivity.kt
class CorrectGuessActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
val binding = ActivityCorrectGuessBinding.inflate(layoutInflater)
val view = binding.root
setContentView(view)
playAgain()
exitGame()
}
fun playAgain() {
binding.btnPlayAgain.setOnClickListener {
val intent = Intent("com.appkotlin2021v4.MainActivity")
startActivity(intent)
}
}

Typically, you define your view binding in the root of your Activity or Fragment or in an init block:
class CorrectGuessActivity : AppCompatActivity() {
//get to inflating!
private val binding = ActivityCorrectGuessBinding.inflate(layoutInflater)
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(binding.root)
playAgain()
exitGame()
}
fun playAgain() {
binding.btnPlayAgain.setOnClickListener {
val intent = Intent("com.appkotlin2021v4.MainActivity")
startActivity(intent)
}
}
The only time you need to "wait to inflate" is when you're in a non-ViewGroup-based class like RecyclerView.Adapter, etc.

Yes, this is the correct way to define the view binding. thank you!

How to initialize and use UI elements

I am currently working on my first Android app using Kotlin. In my activity are a lot of UI elements which I use to show dynamic information (see example below). For performance reasons I learned:
"Define a variable in the class and initialize it in the onCreate()
method."
This is kind of messy and my question is: are there other techniques to fulfill the same task but have a cleaner code? The variables are used in other methods later.
class MainActivity : AppCompatActivity() {
private lateinit var text_1: TextView
private lateinit var text_2: TextView
private lateinit var text_3: TextView
private lateinit var text_4: TextView
[...]
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
text_1 = findViewById(R.id.text1)
text_2 = findViewById(R.id.text2)
text_3 = findViewById(R.id.text3)
text_4 = findViewById(R.id.text4)
[...]
}

From ViewBinding official docs:
View binding is a feature that allows you to more easily write code that interacts with views
First, enable ViewBinding in your module:
android {
...
buildFeatures {
viewBinding true
}
}
Then, if you're calling views from activity, you should:
private lateinit var binding: ResultProfileBinding
override fun onCreate(savedInstanceState: Bundle) {
super.onCreate(savedInstanceState)
binding = ResultProfileBinding.inflate(layoutInflater)
val view = binding.root
setContentView(view)
}
and then you use binding instance to call the views:
binding.name.text = viewModel.name
binding.button.setOnClickListener { viewModel.userClicked() }
If you are calling views from a fragment, you should do it like following to avoid leaks:
private var _binding: ResultProfileBinding? = null
// This property is only valid between onCreateView and
// onDestroyView.
private val binding get() = _binding!!
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
_binding = ResultProfileBinding.inflate(inflater, container, false)
val view = binding.root
return view
}
override fun onDestroyView() {
super.onDestroyView()
_binding = null
}

In Kotlin you just need to use the id directly without binding. The class will import this:
import kotlinx.android.synthetic.main.<your_layout_xml>.*
In this case it will import: kotlinx.android.synthetic.main.activity_main.*
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
text_1.text = "Text1"
text_2.text = "Text2"
[...]
}