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Data binding: Missing required view with ID

I create an app using binding and I get an error that I couldn't solve.
The error is
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.newtest/com.example.mylibrary.MainActivity1}: java.lang.NullPointerException: Missing required view with ID: com.example.newtest:id/myRecyclerview
Thanks!
public class MainActivity1 extends AppCompatActivity {
RecyclerView.LayoutManager layoutManager;
ArrayList<POJOimage>pojoImageArrayList;
ActivityMainBinding binding;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
binding = ActivityMainBinding.inflate(getLayoutInflater());
setContentView(binding.getRoot());
layoutManager = new LinearLayoutManager(this);
binding.myRecyclerview.setLayoutManager(layoutManager);
init();
}
XML:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity1"
android:background="#000"
android:padding="10dp">
<androidx.recyclerview.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/myRecyclerview"/>
</androidx.constraintlayout.widget.ConstraintLayout>

I strongly suspect some Android Studio bug.
I had the same bug, and everything I've had done was adding some TextView.
As it was easy to find this difference, I've just started fiddling with this TextView in xml. At some point bug disappeared.
And here comes the best. Before starting to deal with the problem I've saved problematic change with git. So at the end I've reapplied this change and ... everything worked. No more bug !
P.S. As this bug reappears, I've found that the easiest solution for getting rid of it is to use "Clean Project" from "Build" menu.

Cannot Resolve Symbol activity_sign_up

It says that "cannot resolve the symbol activity_sign_up" when I created a new empty activity:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_sign_up);
}
Added xml resource file code :
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".SignUp">

Rebuild the project and check. If it didn't work just restart the Android studio. Happens for most of the people. Let me know if it worked or will try to help you out differently.

How to include Java jar to C# Xamarin project (Picasso example), problem with ImageView android:src field

I am doing a java to c# transition, and need help.
in Visual Studio 2019 Pro, Android 9.0 (Pie), I am doing this example:
https://learn.microsoft.com/en-us/xamarin/android/platform/binding-java-library/binding-a-jar
The goal is later to convert my java libs to c# for my big project.
I follow the instructions to the letter, and when I come to the part where I need to create an ImageView, there is the problem. Once I create the ImageView, it has an android:src field, something like this (auto generated):
android:src="#drawable/icon"
The problem here, is when I remove that field, in the VS designer, the ImageView disappears and it does not matter if I have the c# code or not, even when I set the srec to:""
Bellow is literally all the code in MainActivity:
using Android.App;
using Android.OS;
using Android.Support.V7.App;
using Android.Runtime;
using Android.Widget;
using Com.Squareup.Picasso;
namespace App3
{
[Activity(Label = "#string/app_name", Theme = "#style/AppTheme", MainLauncher = true)]
public class MainActivity : AppCompatActivity
{
protected override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
Xamarin.Essentials.Platform.Init(this, savedInstanceState);
// Set our view from the "main" layout resource
SetContentView(Resource.Layout.activity_main);
/***********************************************************************/
/**Picasso Code**/
ImageView imageView = FindViewById<ImageView>(Resource.Id.imageView1);
// Use the Picasso jar library to load and display this image:
Picasso.With(this)
.Load("http://i.imgur.com/DvpvklR.jpg")
.Into(imageView);
/**End Ff Picasso Code**/
/***********************************************************************/
}
public override void OnRequestPermissionsResult(int requestCode, string[] permissions, [GeneratedEnum] Android.Content.PM.Permission[] grantResults)
{
Xamarin.Essentials.Platform.OnRequestPermissionsResult(requestCode, permissions, grantResults);
base.OnRequestPermissionsResult(requestCode, permissions, grantResults);
}
}
}
XML Code:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:minWidth="25px"
android:minHeight="25px">
<ImageView
android:src="#drawable/icon" <!-- this line -->
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/imageView1" />
</LinearLayout>
The app does nothing, and in the emulator, the ImageView is empty.
And there is no error, or anything.
If you need anything more, please let me know.
I hope you can help me, if not, thank you for your time.
Edit 1:
It seems, the problem lies in the C# code.
If I add the android:src field, it still does not show up on the emulator, but when I remove the code (the Picasso code) than the image(drawable/icon) shows. Still no error!!

try this
<ImageView
android:src="#drawable/icon" <!-- this line -->
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:minWidth="50px"
android:minHeight="50px"
android:id="#+id/imageView1" />

Android Studio: Resources.NotFoundException

My code ran fine on the emulator, however, as soon as I tried running my code on a device (in this case a Nexus 5) I started to get A LOT of Resources.NotFoundExceptions. The majority of the exceptions occur in relation to drawable or color files. For example:
android.content.res.Resources$NotFoundException: File res/drawable/blob_ocean.xml from drawable resource ID #0x7f060066
Logcat then states that the error is caused by:
Caused by: android.content.res.Resources$NotFoundException: File res/drawable/blob_ocean.xml from drawable resource ID #0x7f060066
then it states that the previous error is caused by:
Caused by: android.content.res.Resources$NotFoundException: File res/color/radial_pink.xml from color state list resource ID #0x7f04004e
The two examples occur in a fragment on the line with the AnimatedVectorDrawable.
public class BlobFragment extends Fragment {
private AnimatedVectorDrawable blob;
private ImageView blobView;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.blob_fragment, container, false);
blobView = (ImageView) v.findViewById(R.id.blob_o);
blob = (AnimatedVectorDrawable) ResourcesCompat.getDrawable(getResources(), R.drawable.blob_ocean, null);
blobView.setImageDrawable(blob);
blob.start();
return v;
}
}
The layout for the fragment looks like this:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".OceanThemeActivity">
<ImageView
android:id="#+id/blob_o"
android:layout_width="300dp"
android:layout_height="300dp"
android:orientation="vertical"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.497"
app:srcCompat="#drawable/blob_ocean"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.271"/>
</androidx.constraintlayout.widget.ConstraintLayout>
I have looked online but have not been able to find something that works. Having a hard time identifying the issue as everything is working fine in an emulator.

I solved the issue. It was related to backward compatibility; I was using AnimatedVectorDrawable which is only working for API 24 or higher and my device was lower. Changing the objects to AnimatedVectorDrawableCompat fixed it. Also, some of the drawable recourses were too big, making them smaller worked perfectly fine.

Hindi font with API level 15 (aka Android 4.0.2)

I have a hindi content based android app and have used devangiri font from Android API 16 SDK and renamed as hindi.ttf. The text renders fine on API level 16 and 17 but simply tears apart in Android API level 15 and lower.
Is there any why I can fix that without removing support for lower API levels. My code for setting textview is:
import android.app.Activity;
import android.graphics.Paint;
import android.graphics.Typeface;
import android.os.Bundle;
import android.view.GestureDetector;
import android.widget.TextView;
public class Prayer extends Activity {
// TextSwitcher vs;
GestureDetector gestureDetector;
static Tips tip = null;
static StringBuilder quesString = null;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.prayer);
TextView tv1 = (TextView) findViewById(R.id.textView1);
Typeface tf = Typeface.createFromAsset(getAssets(), "fonts/hindi.ttf");
tv1.setTypeface(tf);
tv1.setText("श्री");
tv1.setPaintFlags(tv1.getPaintFlags() | Paint.SUBPIXEL_TEXT_FLAG);
}
}
Layout XML:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:ads="http://schemas.android.com/apk/lib/com.google.ads"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#C5C6E1"
tools:context=".Prayer" >
<TextView
android:id="#+id/textView1"
android:layout_width="fill_parent"
android:layout_height="wrap_content" >
</TextView>
</RelativeLayout>
Current:
Expected:

I faced exactly similar issue when I was developing an Hindi app. However, the error resolved when I changed the font files.
Also, IMHO the device simply replaces UTF-8 symbols in text with corresponding symbols in font files. In this case, its showing a completely different symbol altogether. So, the problem should be with font files.
Give me your e-mail in case you want to use my font files.

For Hindi support, I backported the DroidSansDevanagari-Regular.ttf font that was added in Jellybean. You can find all the Jellybean Android fonts in you SDK directory under:
/<Android SDK Dir>/platforms/android-16/data/fonts
If you are still seeing tearing on 4.0.2, you can try:
tv1.setPaintFlags(tv1.getPaintFlags() | Paint.SUBPIXEL_TEXT_FLAG);
When setting a dynamic textSize use this:
tv1.setTextSize(TypedValue.COMPLEX_UNIT_PX, getResources().getDimensionPixelOffset(R.dimen.questionTEXT));