Android Studio Kotlin App Gives Crash FATAL EXCEPTION

February 12, 2022

I am a newbie at android studio and kotlin. Now im working with a firebase login/register app. On the code menu there is error but when i try on avg emulator app shutdown immediately. Can you help me Please

Here is my codes

My Manifest

<?xml version="1.0" encoding="utf-8"?>

<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/Theme.ASSK">
    <activity
        android:name=".RegisterActivity"
        android:exported="false" />
    <activity
        android:name=".LoginActivity"
        android:exported="true">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity
        android:name=".MainActivity"
        android:exported="false" />
</application>

Here is my activity.kt


import android.content.Intent
import android.os.Bundle
import android.widget.Button
import android.widget.EditText
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity
import com.google.android.gms.tasks.OnCompleteListener
import com.google.firebase.auth.AuthResult
import com.google.firebase.auth.FirebaseAuth

import kotlinx.android.synthetic.main.activity_register.*


class LoginActivity : AppCompatActivity()
{
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_login)```

        val btnlogin: Button = findViewById(R.id.btn_login)

        val etemail: EditText = findViewById(R.id.et_login_email)
        val etpassword: EditText = findViewById(R.id.et_login_password)
        btnlogin.setOnClickListener {

            if (etemail.text.toString().trim().isEmpty()) {
                Toast.makeText(
                    this@LoginActivity,
                    "Email Alanını Doldurun",
                    Toast.LENGTH_SHORT
                ).show()

                (etpassword.text.toString().trim().isEmpty())
                Toast.makeText(
                    this@LoginActivity,
                    "Şifre Alanını Doldurun",
                    Toast.LENGTH_SHORT
                ).show()
            } else {

                val email: String = etemail.text.toString().trim { it <= ' ' }
                val password: String = etpassword.text.toString().trim { it <= ' ' }

                FirebaseAuth.getInstance().signInWithEmailAndPassword(email, password)
                    .addOnCompleteListener(
                        OnCompleteListener<AuthResult> { task ->

                            if (task.isSuccessful) {

                                Toast.makeText(
                                    this@LoginActivity,
                                    "Başarı İle Giriş Yapıldı",
                                    Toast.LENGTH_SHORT
                                ).show()

                                val intent =
                                    Intent(this@LoginActivity, MainActivity::class.java)
                                intent.flags =
                                    Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TASK
                                intent.putExtra(
                                    "user_id", FirebaseAuth.getInstance().currentUser!!.uid)
                                intent.putExtra("email_id", email)
                                startActivity(intent)
                                finish()
                            } else {
                                Toast.makeText(
                                    this@LoginActivity,
                                    task.exception!!.message.toString(),
                                    Toast.LENGTH_SHORT
                                ).show()
                            }
                        }
                    )


            }

        }
    }
}

Idk why but import part and some of codes nor formatted sorry for that.

And for the last here is my layout.xml

<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=".LoginActivity"
    android:background="@drawable/background">


    <TextView
        android:id="@+id/tv_title"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="225dp"
        android:fontFamily="@font/league_spartan_bold"
        android:text="Giriş Yap"
        android:textColor="#222934"
        android:textSize="25sp"
        android:textStyle="normal"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <com.google.android.material.textfield.TextInputLayout
        android:id="@+id/et_login_email"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginStart="20dp"
        android:layout_marginTop="50dp"
        android:layout_marginEnd="20dp"
        android:inputType="textEmailAddress"
        app:helperText="Zorunlu"
        app:helperTextTextColor="@android:color/holo_red_dark"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/tv_title"
        tools:text="abc@gmail.com"
        android:hint="E-Mail">

        <EditText
            android:id="@+id/til_login_email"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:inputType="textEmailAddress"
            tools:text="abc@gmail.com">
        </EditText>
    </com.google.android.material.textfield.TextInputLayout>

    <com.google.android.material.textfield.TextInputLayout
        android:id="@+id/til_login_password"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginStart="20dp"
        android:layout_marginTop="10dp"
        android:layout_marginEnd="20dp"
        android:hint="Şifre"
        app:helperText="Zorunlu"
        app:helperTextTextColor="@android:color/holo_red_dark"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/et_login_email">

        <EditText
            android:id="@+id/et_login_password"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:inputType="textPassword"
            tools:text="123456">
        </EditText>
    </com.google.android.material.textfield.TextInputLayout>

    <Button
        android:id="@+id/btn_login"
        android:foreground="?attr/selectableItemBackground"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_marginStart="20dp"
        android:layout_marginTop="10dp"
        android:layout_marginEnd="20dp"
        android:background="@color/gri"
        android:gravity="center"
        android:text="Giriş Yap"
        android:textColor="@android:color/white"
        android:textSize="18sp"
        android:textStyle="bold"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/til_login_password" />

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="5dp"
        android:gravity="center_vertical"
        android:orientation="horizontal"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/btn_login">

        <TextView
            android:id="@+id/tv_dont_have_account"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="16dp"
            android:fontFamily="sans-serif-medium"
            android:padding="5dp"
            android:text="Mevcut Hesabın Yok mu ?">
        </TextView>

        <TextView
            android:id="@+id/tv_register"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="16dp"
            android:fontFamily="@font/league_spartan_bold"
            android:foreground="?attr/selectableItemBackground"
            android:padding="5dp"
            android:text="Kayıt Ol"
            android:textStyle="normal">
        </TextView>
    </LinearLayout>


</androidx.constraintlayout.widget.ConstraintLayout>

And here is my logcat report

    Process: com.example.assk, PID: 6762
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.assk/com.example.assk.LoginActivity}: java.lang.ClassCastException: com.google.android.material.textfield.TextInputLayout cannot be cast to android.widget.EditText
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3449)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3601)
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:85)
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2066)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loop(Looper.java:223)
        at android.app.ActivityThread.main(ActivityThread.java:7656)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)
     Caused by: java.lang.ClassCastException: com.google.android.material.textfield.TextInputLayout cannot be cast to android.widget.EditText
        at com.example.assk.LoginActivity.onCreate(LoginActivity.kt:23)
        at android.app.Activity.performCreate(Activity.java:8000)
        at android.app.Activity.performCreate(Activity.java:7984)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1309)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3422)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3601) 
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:85) 
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) 
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2066) 
        at android.os.Handler.dispatchMessage(Handler.java:106) 
        at android.os.Looper.loop(Looper.java:223) 
        at android.app.ActivityThread.main(ActivityThread.java:7656) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)```

The format error happened again idk why it happens sorry for that. So here is my all codes what can i do pls help me

>Solution :

you are referencing to wrong view just change your code like this:

    val btnlogin: Button = findViewById(R.id.btn_login)
    val etemail: EditText = findViewById(R.id.til_login_email)
    val etpassword: EditText = findViewById(R.id.et_login_password)

This should solve your problem.