Develop Reference

Unable to Sign in with google

I have to add sign in with google feature to my app. I have tried several tutorials but nothing works. Whenever I select an account from the list, that pop up gets closed and nothing happens. I don't know what is the problem since there is no errors showing on the logcat.
Login.java
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.RelativeLayout;
import android.widget.Toast;
import com.google.android.gms.auth.api.signin.GoogleSignIn;
import com.google.android.gms.auth.api.signin.GoogleSignInAccount;
import com.google.android.gms.auth.api.signin.GoogleSignInClient;
import com.google.android.gms.auth.api.signin.GoogleSignInOptions;
import com.google.android.gms.common.api.ApiException;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.AuthCredential;
import com.google.firebase.auth.AuthResult;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.auth.FirebaseUser;
import com.google.firebase.auth.GoogleAuthProvider;
public class Login extends AppCompatActivity {
GoogleSignInClient mGoogleSignInClient;
FirebaseAuth auth;
RelativeLayout googlesignin;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
auth = FirebaseAuth.getInstance();
GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
.requestIdToken(getString(R.string.default_web_client_id))
.requestEmail()
.build();
mGoogleSignInClient = GoogleSignIn.getClient(this,gso);
googlesignin = (RelativeLayout) findViewById(R.id.googlesignin);
googlesignin.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent signInIntent = mGoogleSignInClient.getSignInIntent();
startActivityForResult(signInIntent, 101);
}
});
}
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == 101) {
Task<GoogleSignInAccount> task = GoogleSignIn.getSignedInAccountFromIntent(data);
try {
GoogleSignInAccount account = task.getResult(ApiException.class);
firebaseAuthWithGoogle(account);
} catch (ApiException e) {
}
}
}
private void firebaseAuthWithGoogle(GoogleSignInAccount account) {
AuthCredential credential = GoogleAuthProvider.getCredential(account.getIdToken(), null);
auth.signInWithCredential(credential)
.addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
#Override
public void onComplete(#NonNull Task<AuthResult> task) {
if (task.isSuccessful()) {
FirebaseUser user = auth.getCurrentUser();
Intent i = new Intent(getApplicationContext(),Homewindow.class);
startActivity(i);
finish();
Toast.makeText(getApplicationContext(),"User Logged In Successfully",Toast.LENGTH_SHORT).show();
}
else {
Toast.makeText(getApplicationContext(),"Login Failed",Toast.LENGTH_SHORT).show();
}
}
});
}
}
activity_login
<RelativeLayout
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"
android:background="#00BFFF"
android:orientation="vertical"
android:scrollbarAlwaysDrawVerticalTrack="true">
<RelativeLayout
android:id="#+id/loginmain"
android:layout_width="match_parent"
android:layout_height="match_parent">
<RelativeLayout
android:id="#+id/logincontents"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:background="#drawable/relativelayout_custom"
android:orientation="vertical"
android:padding="20dp">
<RelativeLayout
android:id="#+id/googlesignin"
android:layout_width="match_parent"
android:layout_height="50dp"
android:layout_marginTop="40dp"
android:orientation="horizontal"
android:background="#drawable/loginlayout">
<ImageView
android:id="#+id/googleicon"
android:layout_width="40dp"
android:layout_height="40dp"
android:layout_centerVertical="true"
android:layout_marginLeft="20dp"
android:src="#drawable/googleicon"/>
<TextView
android:id="#+id/googletext"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="20dp"
android:layout_centerVertical="true"
android:layout_toRightOf="#id/googleicon"
android:fontFamily="#font/averia_gruesa_libre"
android:text="Sign in with Google"
android:textColor="#db3236"
android:textSize="14dp"
android:textStyle="bold" />
</RelativeLayout>
<RelativeLayout
android:id="#+id/facebooksignin"
android:layout_width="match_parent"
android:layout_height="50dp"
android:orientation="horizontal"
android:layout_below="#id/googlesignin"
android:layout_marginTop="40dp"
android:background="#drawable/loginlayout">
<ImageView
android:id="#+id/facebookicon"
android:layout_width="40dp"
android:layout_height="40dp"
android:layout_centerVertical="true"
android:layout_marginLeft="20dp"
android:src="#drawable/facebookicon"/>
<TextView
android:id="#+id/facebooktext"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerVertical="true"
android:layout_marginLeft="20dp"
android:fontFamily="#font/averia_gruesa_libre"
android:layout_toRightOf="#id/facebookicon"
android:text="Sign in with Facebook"
android:textColor="#3b5998"
android:textSize="14dp"
android:textStyle="bold" />
</RelativeLayout>
<TextView
android:id="#+id/skipbutton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/facebooksignin"
android:layout_centerHorizontal="true"
android:layout_marginTop="40dp"
android:fontFamily="#font/averia_gruesa_libre"
android:paddingTop="5dp"
android:text="SKIP NOW >>"
android:textColor="#00BFFF"
android:textStyle="bold" />
</RelativeLayout>
<RelativeLayout
android:id="#+id/profileicon"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="40dp"
android:layout_above="#id/logincontents">
<androidx.appcompat.widget.AppCompatImageView
android:layout_width="60dp"
android:layout_height="60dp"
android:layout_centerHorizontal="true"
android:src="#drawable/profile_icon"/>
</RelativeLayout>
</RelativeLayout>
</RelativeLayout>
Here I used onClickListener for the Relative layout containing googleicon and text.
build.gradle (app)
apply plugin: 'com.android.application'
android {
compileSdkVersion 29
buildToolsVersion "29.0.1"
defaultConfig {
vectorDrawables.useSupportLibrary = true
applicationId "com.example.parethumukal"
minSdkVersion 18
targetSdkVersion 29
versionCode 1
versionName "1.0"
testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation 'androidx.appcompat:appcompat:1.0.2'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
implementation 'com.google.firebase:firebase-auth:18.1.0'
implementation 'com.google.android.gms:play-services-auth:17.0.0'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'androidx.test:runner:1.2.0'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
//noinspection GradleCompatible
implementation "com.google.android.material:material:1.0.0-rc01"
implementation 'com.github.bumptech.glide:glide:4.3.1'
annotationProcessor 'com.github.bumptech.glide:compiler:4.3.1'
//noinspection GradleCompatible
def lifecycle_version = "2.0.0"
// ViewModel and LiveData
implementation "androidx.lifecycle:lifecycle-extensions:$lifecycle_version"
implementation files('libs\\YouTubeAndroidPlayerApi.jar')
implementation 'com.google.firebase:firebase-core:17.0.0'
implementation 'com.google.firebase:firebase-database:18.0.0'
implementation 'com.google.firebase:firebase-storage:18.1.0'
implementation 'de.hdodenhof:circleimageview:3.0.0'
}
apply plugin: 'com.google.gms.google-services'
build.gradle(project)
// Top-level build file where you can add configuration options common to all sub-projects/modules.
buildscript {
repositories {
google()
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:3.4.2'
classpath 'com.google.gms:google-services:4.2.0'
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
}
allprojects {
repositories {
google()
jcenter()
maven {
url "https://maven.google.com"
}
maven { url 'https://jitpack.io' }
}
}
task clean(type: Delete) {
delete rootProject.buildDir
}
logcat error
07-23 21:48:22.994 21934-21934/com.example.parethumukal E/MultiWindowProxy: getServiceInstance failed!
07-23 21:48:27.924 21934-21982/com.example.parethumukal E/Surface: getSlotFromBufferLocked: unknown buffer: 0xb37a4d60
I don't know if any errors with my codes. Codes are taken from firebase site.

Try this
GoogleSignInOptions gso;
GoogleApiClient googleApiClient;
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
.requestIdToken(getString(R.string.firebase_web_client_id))
.requestEmail()
.build();
googleApiClient = new GoogleApiClient.Builder(getApplicationContext())
.enableAutoManage(this, null)
.addApi(Auth.GOOGLE_SIGN_IN_API, gso)
.build();
}

Why am i getting a class cast exception when adding a button in android studio?

I'm on Android Studio 3.4, and using Material Design.
When I add a button to the layout i'm getting a java.lang.ClassCastException#11378fc8 and i can't use anymore the layout editor until I remove the button.
I have already tried to "invalidate/restart", to rebuild, to clean and build.
This is my tree structure :
Tree structure
Build.Gradle :
apply plugin: 'com.android.application'
android {
compileSdkVersion 28
defaultConfig {
applicationId "fr.aurelien.test_dessin_android"
minSdkVersion 24
targetSdkVersion 28
versionCode 1
versionName "1.0"
testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation 'androidx.appcompat:appcompat:1.0.0-beta01'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
implementation 'androidx.legacy:legacy-support-v4:1.0.0-beta01'
implementation 'com.google.android.material:material:1.1.0-alpha06'
implementation 'com.google.code.gson:gson:2.8.5'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'androidx.test:runner:1.1.0-alpha4'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.0-alpha4'
}
Class cast exception :
java.lang.IllegalArgumentException: java.lang.ClassCastException#126d0c4
at sun.reflect.GeneratedMethodAccessor1380.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at android.animation.PropertyValuesHolder_Delegate.callMethod(PropertyValuesHolder_Delegate.java:108)
at android.animation.PropertyValuesHolder_Delegate.nCallFloatMethod(PropertyValuesHolder_Delegate.java:143)
at android.animation.PropertyValuesHolder.nCallFloatMethod(PropertyValuesHolder.java)
at android.animation.PropertyValuesHolder.access$400(PropertyValuesHolder.java:38)
at android.animation.PropertyValuesHolder$FloatPropertyValuesHolder.setAnimatedValue(PropertyValuesHolder.java:1387)
at android.animation.ObjectAnimator.animateValue(ObjectAnimator.java:990)
at android.animation.ValueAnimator.setCurrentFraction(ValueAnimator.java:674)
at android.animation.ValueAnimator.start(ValueAnimator.java:1071)
at android.animation.ValueAnimator.start(ValueAnimator.java:1088)
at android.animation.ObjectAnimator.start(ObjectAnimator.java:852)
at android.animation.ValueAnimator.startWithoutPulsing(ValueAnimator.java:1081)
at android.animation.AnimatorSet.handleAnimationEvents(AnimatorSet.java:1142)
at android.animation.AnimatorSet.doAnimationFrame(AnimatorSet.java:1046)
at android.animation.AnimationHandler.doAnimationFrame(AnimationHandler.java:146)
at android.animation.AnimationHandler.access$100(AnimationHandler.java:37)
at android.animation.AnimationHandler$1.doFrame(AnimationHandler.java:54)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:947)
at android.view.Choreographer.doCallbacks(Choreographer.java:761)
at android.view.Choreographer_Delegate.doFrame(Choreographer_Delegate.java:66)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.renderAndBuildResult(RenderSessionImpl.java:563)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.render(RenderSessionImpl.java:425)
at com.android.layoutlib.bridge.BridgeRenderSession.render(BridgeRenderSession.java:120)
at com.android.ide.common.rendering.api.RenderSession.render(RenderSession.java:151)
at com.android.ide.common.rendering.api.RenderSession.render(RenderSession.java:133)
at com.android.tools.idea.rendering.RenderTask.lambda$null$8(RenderTask.java:755)
at java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1590)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
MainActivity :
package fr.aurelien.test_dessin_android;
import androidx.fragment.app.FragmentManager;
import androidx.fragment.app.FragmentTransaction;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
FragmentManager fragmentManager = getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.add(R.id.frameLayout, new SimpleFragment());
fragmentTransaction.commit();
}
}
Fragment class :
package fr.aurelien.test_dessin_android;
import android.os.Bundle;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
public class SimpleFragment extends Fragment {
#Nullable
#Override
public View onCreateView(#NonNull LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View retView = inflater.inflate(R.layout.fragment_layout, container, false);
return retView;
}
}
Manifest.xml :
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="fr.aurelien.test_dessin_android">
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/AppTheme.default">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
XML code :
<?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">
<TextView
android:id="#+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="70dp"
android:layout_marginTop="16dp"
android:text="TextView"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<ImageView
android:id="#+id/imageView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="55dp"
android:layout_marginTop="31dp"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/textView"
app:srcCompat="#mipmap/ic_launcher" />
<Button
android:id="#+id/button5"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:text="Button"
app:layout_constraintTop_toTopOf="parent"
tools:layout_editor_absoluteX="189dp" />
</androidx.constraintlayout.widget.ConstraintLayout>

It's a bug in Android Studio. You can track it here, it's apparently fixed for 3.5.2 https://issuetracker.google.com/issues/132316448

Have you tried using androidx.appcompat.widget.AppCompatButton instead of Button?

If you want to use material components you need to change your default theme in styles.xml from Theme.AppCompat to Theme.MaterialComponents.
Don't forget to add this
implementation 'com.google.android.material:material:1.1.0' in your app level build.gradle

Live ads from Admob is not showing

Yesterday I created an account on Admob and on my app the test ads working well but the live (real) ads not showing. When I added onFaildToLoad event it returns INTERNAL_ERROR. So is there any solutions? and is it important to upload the app on play store to get live ads?
Here is my xml file:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
xmlns:android="http://schemas.android.com/apk/res/android">
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1">
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="208dp"
android:text="login" />
<EditText
android:id="#+id/editText"
android:layout_width="297dp"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="183dp"
android:ems="10"
android:inputType="textPassword" />
</RelativeLayout>
<com.google.android.gms.ads.AdView
xmlns:ads="http://schemas.android.com/apk/res-auto"
android:id="#+id/adView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_alignParentBottom="true"
ads:adSize="BANNER"
ads:adUnitId="ca-app-pub-8140603259324677/7029410922">
</com.google.android.gms.ads.AdView>
</LinearLayout>
and this is my java code:
package com.example.moamen.webbrowser;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import com.google.android.gms.ads.AdListener;
import com.google.android.gms.ads.MobileAds;
import com.google.android.gms.ads.AdRequest;
import com.google.android.gms.ads.AdView;
import static com.google.android.gms.ads.AdRequest.ERROR_CODE_INTERNAL_ERROR;
import static com.google.android.gms.ads.AdRequest.ERROR_CODE_INVALID_REQUEST;
import static com.google.android.gms.ads.AdRequest.ERROR_CODE_NETWORK_ERROR;
import static com.google.android.gms.ads.AdRequest.ERROR_CODE_NO_FILL;
public class LoginActivity extends AppCompatActivity {
Button mButton;
EditText mEditText;
private AdView mAdView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
mAdView = findViewById(R.id.adView);
AdRequest adRequest = new AdRequest.Builder().build();
try {
mAdView.loadAd(adRequest);
} catch (Exception e) {
e.printStackTrace();
}
mEditText = (EditText) findViewById(R.id.editText);
mButton = (Button) findViewById(R.id.button);
final String passA= "facebook";
final String passB = "moa";
// Sample AdMob app ID: ca-app-pub-3940256099942544~3347511713
MobileAds.initialize(this, "ca-app-pub-8140603259324677~4251010820");
mButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String text = mEditText.getText().toString().trim();
if (text.equals(passA)){
Intent intent = new Intent(LoginActivity.this,MainActivity.class);
intent.putExtra("website","https://www.facebook.com/");
startActivity(intent);
}else if (text.equals(passB) ){
Intent intent = new Intent(LoginActivity.this,MainActivity.class);
intent.putExtra("website","https://www.google.com/");
startActivity(intent);
}else {
Toast.makeText(LoginActivity.this, "Password is incorrect", Toast.LENGTH_SHORT).show();
}
}
});
mAdView.setAdListener(new AdListener(){
#Override
public void onAdFailedToLoad(int errorCode) {
// Code to be executed when an ad request fails.
if (errorCode == ERROR_CODE_INTERNAL_ERROR){
Toast.makeText(LoginActivity.this,"ERROR_CODE_INTERNAL_ERROR",Toast.LENGTH_SHORT).show();
}else if (errorCode == ERROR_CODE_INVALID_REQUEST){
Toast.makeText(LoginActivity.this,"ERROR_CODE_INVALID_REQUEST",Toast.LENGTH_SHORT).show();
}else if (errorCode == ERROR_CODE_NETWORK_ERROR){
Toast.makeText(LoginActivity.this,"ERROR_CODE_NETWORK_ERROR",Toast.LENGTH_SHORT).show();
}else if (errorCode == ERROR_CODE_NO_FILL){
Toast.makeText(LoginActivity.this,"ERROR_CODE_NO_FILL",Toast.LENGTH_SHORT).show();
}
}
});
}
}
this is my gardle.build file:
apply plugin: 'com.android.application'
android {
compileSdkVersion 28
defaultConfig {
applicationId "com.example.drshimaa.webbrowser"
minSdkVersion 19
targetSdkVersion 28
versionCode 1
versionName "1.0"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
//noinspection GradleCompatible
implementation 'com.android.support:appcompat-v7:28.0.0-alpha1'
implementation 'com.android.support.constraint:constraint-layout:1.1.3'
implementation 'com.android.support:design:28.0.0-rc02'
implementation 'com.google.android.gms:play-services-ads:15.0.0'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'com.android.support.test:runner:1.0.2'
androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
}
allprojects {
repositories {
jcenter()
maven {
url "https://maven.google.com"
}
}
}
the error
test ads is working well

If you are getting TestAds then your implementation is correct.
Change your package id and check

If you have recently created an AdUnit, then you have to wait for sometime to let the AdUnits get Activated...

Chat with Firestore crashes with NullPointerException on RecyclerView.setHasFixedSize

I am pretty new to RecyclerView, so please forgive me if the resolution is very simple. I digged around but no luck so I need guidance.
Adapting the Chat with FirebaseUI with Firestore grabbing the code from https://github.com/firebase/FirebaseUI-Android.
Here is the main code:
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import com.firebase.ui.auth.util.ui.ImeHelper;
import com.firebase.ui.firestore.FirestoreRecyclerAdapter;
import com.firebase.ui.firestore.FirestoreRecyclerOptions;
import com.google.android.gms.tasks.OnFailureListener;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.firestore.CollectionReference;
import com.google.firebase.firestore.FirebaseFirestore;
import com.google.firebase.firestore.Query;
import butterknife.BindView;
import butterknife.ButterKnife;
import butterknife.OnClick;
/**
* Class demonstrating how to setup a {#link RecyclerView} with an adapter while taking sign-in
* states into consideration. Also demonstrates adding data to a ref and then reading it back using
* the {#link FirestoreRecyclerAdapter} to build a simple chat app.
* <p>
* For a general intro to the RecyclerView, see <a href="https://developer.android.com/training/material/lists-cards.html">Creating
* Lists</a>.
*/
public class BlaBlaBlaChat extends AppCompatActivity
implements FirebaseAuth.AuthStateListener {
private static final String TAG = "BlaBlaBlaChat";
private static final CollectionReference sChatCollection =
FirebaseFirestore.getInstance().collection("chats");
/** Get the last 50 chat messages ordered by timestamp . */
private static final Query sChatQuery = sChatCollection.orderBy("timestamp").limit(50);
static {
FirebaseFirestore.setLoggingEnabled(true);
}
#BindView(R.id.messagesList)
RecyclerView mRecyclerView;
#BindView(R.id.sendButton)
Button mSendButton;
#BindView(R.id.messageEdit)
EditText mMessageEdit;
#BindView(R.id.emptyTextView)
TextView mEmptyListMessage;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.ireland_chat);
ButterKnife.bind(this);
mRecyclerView.setHasFixedSize(true);
mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
ImeHelper.setImeOnDoneListener(mMessageEdit, new ImeHelper.DonePressedListener() {
#Override
public void onDonePressed() {
onSendClick();
}
});
}
#Override
public void onStart() {
super.onStart();
if (isSignedIn()) { attachRecyclerViewAdapter(); }
FirebaseAuth.getInstance().addAuthStateListener(this);
}
#Override
protected void onStop() {
super.onStop();
FirebaseAuth.getInstance().removeAuthStateListener(this);
}
#Override
public void onAuthStateChanged(#NonNull FirebaseAuth auth) {
mSendButton.setEnabled(isSignedIn());
mMessageEdit.setEnabled(isSignedIn());
if (isSignedIn()) {
attachRecyclerViewAdapter();
} else {
Toast.makeText(this, R.string.signing_in, Toast.LENGTH_SHORT).show();
auth.signInAnonymously().addOnCompleteListener(new BlaBlaBlaChatSignInHolder(this));
}
}
private boolean isSignedIn() {
return FirebaseAuth.getInstance().getCurrentUser() != null;
}
private void attachRecyclerViewAdapter() {
final RecyclerView.Adapter adapter = newAdapter();
// Scroll to bottom on new messages
adapter.registerAdapterDataObserver(new RecyclerView.AdapterDataObserver() {
#Override
public void onItemRangeInserted(int positionStart, int itemCount) {
mRecyclerView.smoothScrollToPosition(adapter.getItemCount());
}
});
mRecyclerView.setAdapter(adapter);
}
#OnClick(R.id.sendButton)
public void onSendClick() {
String uid = FirebaseAuth.getInstance().getCurrentUser().getUid();
String name = "User " + uid.substring(0, 6);
onAddMessage(new BlaBlaBlaChatAbstractExtend(name, mMessageEdit.getText().toString(), uid));
mMessageEdit.setText("");
}
protected RecyclerView.Adapter newAdapter() {
FirestoreRecyclerOptions<BlaBlaBlaChatAbstractExtend> options =
new FirestoreRecyclerOptions.Builder<BlaBlaBlaChatAbstractExtend>()
.setQuery(sChatQuery, BlaBlaBlaChatAbstractExtend.class)
.setLifecycleOwner(this)
.build();
return new FirestoreRecyclerAdapter<BlaBlaBlaChatAbstractExtend, BlaBlaBlaChatHolder>(options) {
#Override
public BlaBlaBlaChatHolder onCreateViewHolder(ViewGroup parent, int viewType) {
return new BlaBlaBlaChatHolder(LayoutInflater.from(parent.getContext())
.inflate(R.layout.message, parent, false));
}
#Override
protected void onBindViewHolder(#NonNull BlaBlaBlaChatHolder holder, int position, #NonNull BlaBlaBlaChatAbstractExtend model) {
holder.bind(model);
}
#Override
public void onDataChanged() {
// If there are no chat messages, show a view that invites the user to add a message.
mEmptyListMessage.setVisibility(getItemCount() == 0 ? View.VISIBLE : View.GONE);
}
};
}
protected void onAddMessage(BlaBlaBlaChatAbstractExtend chat) {
sChatCollection.add(chat).addOnFailureListener(this, new OnFailureListener() {
#Override
public void onFailure(#NonNull Exception e) {
Log.e(TAG, "Failed to write message", e);
}
});
}
And here is the xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
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="com.example.balblabla.BlaBlaBlaChat">
<TextView
android:id="#+id/emptyTextView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="16dp"
android:text="#string/start_chatting" />
<android.support.v7.widget.RecyclerView
android:id="#+id/messagesList"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentStart="true"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_above="#+id/footer"
android:clipToPadding="false"
android:padding="16dp"
tools:listitem="#layout/ireland_chat_message" />
<LinearLayout
android:id="#+id/footer"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_alignParentLeft="true"
android:layout_alignParentBottom="true"
android:paddingStart="16dp"
android:paddingEnd="16dp"
android:paddingLeft="16dp"
android:orientation="horizontal">
<EditText
android:id="#+id/messageEdit"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:imeOptions="actionDone"
android:inputType="text" />
<Button
android:id="#+id/sendButton"
style="#style/Widget.AppCompat.Button.Borderless.Colored"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|end"
android:text="#string/send" />
</LinearLayout>
</RelativeLayout>
From logcat:
01-12 18:07:36.443 31599-31599/com.example.carlo.blablabla E/UncaughtException: java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.carlo.blablabla/com.example.carlo.blablabla.BlaBlaBlaChat}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.support.v7.widget.RecyclerView.setHasFixedSize(boolean)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2724)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2789)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1527)
at android.os.Handler.dispatchMessage(Handler.java:110)
at android.os.Looper.loop(Looper.java:203)
at android.app.ActivityThread.main(ActivityThread.java:6251)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1063)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:924)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.support.v7.widget.RecyclerView.setHasFixedSize(boolean)' on a null object reference
at com.example.carlo.blablabla.BlaBlaBlaChat.onCreate(BlaBlaBlaChat.java:73)
at android.app.Activity.performCreate(Activity.java:6681)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2677)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2789) 
at android.app.ActivityThread.-wrap12(ActivityThread.java) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1527) 
at android.os.Handler.dispatchMessage(Handler.java:110) 
at android.os.Looper.loop(Looper.java:203) 
at android.app.ActivityThread.main(ActivityThread.java:6251) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1063) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:924) 
01-12 18:07:36.715 31599-31599/com.example.carlo.blablabla E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.carlo.blablabla, PID: 31599
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.carlo.blablabla/com.example.carlo.blablabla.BlaBlaBlaChat}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.support.v7.widget.RecyclerView.setHasFixedSize(boolean)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2724)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2789)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1527)
at android.os.Handler.dispatchMessage(Handler.java:110)
at android.os.Looper.loop(Looper.java:203)
at android.app.ActivityThread.main(ActivityThread.java:6251)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1063)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:924)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.support.v7.widget.RecyclerView.setHasFixedSize(boolean)' on a null object reference
at com.example.carlo.blablabla.BlaBlaBlaChat.onCreate(BlaBlaBlaChat.java:73)
at android.app.Activity.performCreate(Activity.java:6681)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2677)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2789) 
at android.app.ActivityThread.-wrap12(ActivityThread.java) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1527) 
at android.os.Handler.dispatchMessage(Handler.java:110) 
at android.os.Looper.loop(Looper.java:203) 
at android.app.ActivityThread.main(ActivityThread.java:6251) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1063) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:924) 
Gradle Project
// Top-level build file where you can add configuration options common to all sub-projects/modules.
buildscript {
repositories {
jcenter()
google()
}
dependencies {
classpath 'com.android.tools.build:gradle:3.0.1'
classpath 'com.google.gms:google-services:3.1.0'
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
}
allprojects {
repositories {
jcenter()
google()
maven {
url "https://maven.google.com" // Google's Maven repository
}
}
}
task clean(type: Delete) {
delete rootProject.buildDir
}
Gradle APP:
apply plugin: 'com.android.application'
android {
compileSdkVersion 27
buildToolsVersion '26.0.2'
defaultConfig {
applicationId "com.example.blablabla.albalbalb"
minSdkVersion 19
targetSdkVersion 27
versionCode 1
versionName "1.0"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
exclude group: 'com.android.support', module: 'support-annotations'
})
compile 'com.android.support:appcompat-v7:27.0.2'
compile 'com.android.support.constraint:constraint-layout:1.0.2'
testCompile 'junit:junit:4.12'
compile 'com.google.android.gms:play-services-location:11.8.0'
compile 'com.google.android.gms:play-services-maps:11.8.0'
compile 'com.google.firebase:firebase-core:11.8.0'
compile 'com.google.firebase:firebase-auth:11.8.0'
compile 'com.google.firebase:firebase-firestore:11.8.0'
compile 'com.google.firebase:firebase-storage:11.8.0'
implementation 'com.android.support:cardview-v7:27.0.2'
implementation 'com.android.support:recyclerview-v7:27.0.2'
compile 'de.hdodenhof:circleimageview:1.3.0'
compile 'com.google.android.gms:play-services-appinvite:11.8.0'
compile 'com.google.firebase:firebase-messaging:11.8.0'
compile 'com.google.android.gms:play-services-ads:11.8.0'
compile 'com.google.firebase:firebase-appindexing:11.8.0'
compile 'com.google.firebase:firebase-crash:11.8.0'
compile 'com.google.firebase:firebase-analytics:11.8.0'
compile 'com.android.support:design:27.0.2'
compile 'com.github.bumptech.glide:glide:4.3.1'
compile 'com.google.firebase:firebase-database:11.8.0'
compile 'com.google.firebase:firebase-config:11.8.0'
compile 'com.firebaseui:firebase-ui-database:3.1.3'
compile 'com.firebaseui:firebase-ui-auth:3.1.3'
implementation 'com.firebaseui:firebase-ui-firestore:3.1.3'
implementation 'com.firebaseui:firebase-ui-storage:3.1.3'
compile 'com.google.android.gms:play-services-auth:11.8.0'
implementation 'com.jakewharton:butterknife:8.8.1'
// Testing dependencies
androidTestCompile 'com.android.support.test:runner:1.0.1'
androidTestCompile 'com.android.support:support-annotations:27.0.2'
}
apply plugin: 'com.google.gms.google-services'
The code is just a cut/paste from the Github code, but something went wrong.

It looks like you didn't add the ButterKnife library to your project correctly.
In your app's build.gradle file, you must add the annotationProcessor after implementation "com.jakewharton:butterknife:8.8.1" like this:
annotationProcessor "com.jakewharton:butterknife-compiler:8.8.1"
And in your project's build.gradle file add the ButterKnife plugin to your buildscript:
dependencies {
classpath 'com.android.tools.build:gradle:3.0.1'
classpath 'com.google.gms:google-services:3.1.0'
classpath 'com.jakewharton:butterknife-gradle-plugin:8.8.1'
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}

You are using mRecyclerView which is never initialized and that's why you are getting that error. In order to solve this, you must first initialize it before you use it. Assuming that the id of your RecyclerView is recycler_view, please use the following code in your onCreate() method:
RecyclerView mRecyclerView = (RecyclerView) findViewById(R.id.recycler_view);

Firebase Auth not working on emulator: class for com.google.firebase.auth not found

Im getting a "registration error" when I run my code and my online firebase users data is not getting updated. I checked my google play services version and updated gradle to compile with that version as I thought a later version would not work on my emulator, on my firebase project I have enabled "email/password" but my users database is not getting updated and I am throwing the "registration error" exception in my code, my password I am using is 10 characters long and contains one uppercase, some numbers and a hash just to be sure. Why is my database not getting updated, I suspected the google play services version but have downgraded this to the version my emulator is running and suspected my password but am using a more complex one but am still throwing a registration exception. I have added internet permissions on my manifest as I thought that could be a problem as well.
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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"
android:orientation="vertical"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.swaziprocurement.mobileappie.MainActivity">
<LinearLayout
android:layout_centerVertical="true"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<EditText
android:id="#+id/editTextEmail"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="15dp"
android:hint="Enter email"
android:inputType="textEmailAddress" />
<EditText
android:id="#+id/editTextPassword"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="15dp"
android:hint="Enter password"
android:inputType="textPassword" />
<Button
android:id="#+id/buttonSignup"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="15dp"
android:text="Signup" />
</LinearLayout>
</RelativeLayout>
Main Activity:
package com.swaziprocurement.mobileappie;
import android.app.ProgressDialog;
import android.support.annotation.NonNull;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.AuthResult;
import com.google.firebase.auth.FirebaseAuth;
public class MainActivity extends AppCompatActivity {
private FirebaseAuth firebaseAuth;
private EditText editTextEmail;
private EditText editTextPassword;
private Button buttonSignup;
private ProgressDialog progressDialog;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
firebaseAuth = FirebaseAuth.getInstance();
editTextEmail = (EditText) findViewById(R.id.editTextEmail);
editTextPassword = (EditText) findViewById(R.id.editTextPassword);
buttonSignup = (Button) findViewById(R.id.buttonSignup);
progressDialog = new ProgressDialog(this);
buttonSignup.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
registerUser();
}
});
}
private void registerUser(){
//getting email and password from edit texts
String email = editTextEmail.getText().toString().trim();
String password = editTextPassword.getText().toString().trim();
//checking if email and passwords are empty
if(TextUtils.isEmpty(email)){
Toast.makeText(this,"Please enter email",Toast.LENGTH_LONG).show();
return;
}
if(TextUtils.isEmpty(password)){
Toast.makeText(this,"Please enter password",Toast.LENGTH_LONG).show();
return;
}
//if the email and password are not empty
//displaying a progress dialog
progressDialog.setMessage("Registering Please Wait...");
progressDialog.show();
//creating a new user
firebaseAuth.createUserWithEmailAndPassword(email, password)
.addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
#Override
public void onComplete(#NonNull Task<AuthResult> task) {
//checking if success
if(task.isSuccessful()){
//display some message here
Toast.makeText(MainActivity.this,"Successfully registered",Toast.LENGTH_LONG).show();
}else{
//display some message here
Toast.makeText(MainActivity.this,"Registration Error", Toast.LENGTH_LONG).show();
}
progressDialog.dismiss();
}
});
}
}
Gradle:
// Top-level build file where you can add configuration options common to all sub-projects/modules.
buildscript {
repositories {
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:2.1.2'
classpath 'com.google.gms:google-services:3.0.0'
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
}
allprojects {
repositories {
jcenter()
}
}
task clean(type: Delete) {
delete rootProject.buildDir
}
Gradle (Module App)
apply plugin: 'com.android.application'
android {
compileSdkVersion 24
buildToolsVersion "24.0.1"
defaultConfig {
applicationId "com.swaziprocurement.mobileappie"
minSdkVersion 17
targetSdkVersion 24
versionCode 1
versionName "1.0"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
testCompile 'junit:junit:4.12'
compile 'com.android.support:appcompat-v7:24.1.1'
compile 'com.google.firebase:firebase-auth:9.2.0'
compile 'com.google.android.gms:play-services-auth:9.2.0'
}
apply plugin: 'com.google.gms.google-services'
Manifest:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.swaziprocurement.mobileappie">
<uses-permission android:name="android.permission.INTERNET" />
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
logcat log:
09-25 12:00:18.324 14451-14613/com.swaziprocurement.mobileappie W/DynamiteModule: Local module descriptor class for com.google.firebase.auth not found.
09-25 12:00:18.332 14451-14613/com.swaziprocurement.mobileappie W/DynamiteModule: Local module descriptor class for com.google.firebase.auth not found.
09-25 12:00:28.457 14451-14613/com.swaziprocurement.mobileappie W/DynamiteModule: Local module descriptor class for com.google.firebase.auth not found.

I finally sorted it out, it was that I required to update my system images on my API build tools and update my system images on my emulator, that got it working