Android Java App crashing after Button Click

Hello everyone, I was following the Youtube FCC tutorial on Android Java development and trying to complete the first challenge.

I thought I followed everything but my app keeps crashing after the button click. Does anyone have an idea how to fix this?

Java file: Java file - Pastebin.com
XML file: XML file - Pastebin.com

Logcat debug :

2022-03-29 10:31:41.683 5792-5792/com.example.myapplication1 E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.myapplication1, PID: 5792
java.lang.IllegalStateException: Could not execute method for android:onClick
at androidx.appcompat.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:414)
at android.view.View.performClick(View.java:7455)
at com.google.android.material.button.MaterialButton.performClick(MaterialButton.java:1119)
at android.view.View.performClickInternal(View.java:7432)
at android.view.View.access$3700(View.java:835)
at android.view.View$PerformClick.run(View.java:28810)
at android.os.Handler.handleCallback(Handler.java:938)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loopOnce(Looper.java:201)
at android.os.Looper.loop(Looper.java:288)
at android.app.ActivityThread.main(ActivityThread.java:7842)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Method.invoke(Native Method)
at androidx.appcompat.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:409)
at android.view.View.performClick(View.java:7455)
at com.google.android.material.button.MaterialButton.performClick(MaterialButton.java:1119)
at android.view.View.performClickInternal(View.java:7432)
at android.view.View.access$3700(View.java:835)
at android.view.View$PerformClick.run(View.java:28810)
at android.os.Handler.handleCallback(Handler.java:938)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loopOnce(Looper.java:201)
at android.os.Looper.loop(Looper.java:288)
at android.app.ActivityThread.main(ActivityThread.java:7842)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
Caused by: java.lang.ClassCastException: com.google.android.material.textview.MaterialTextView cannot be cast to android.widget.EditText
at com.example.myapplication1.MainActivity.onBtnClick(MainActivity.java:29)
at java.lang.reflect.Method.invoke(Native Method)
at androidx.appcompat.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:409)
at android.view.View.performClick(View.java:7455)
at com.google.android.material.button.MaterialButton.performClick(MaterialButton.java:1119)
at android.view.View.performClickInternal(View.java:7432)
at android.view.View.access$3700(View.java:835)
at android.view.View$PerformClick.run(View.java:28810)
at android.os.Handler.handleCallback(Handler.java:938)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loopOnce(Looper.java:201)
at android.os.Looper.loop(Looper.java:288)
at android.app.ActivityThread.main(ActivityThread.java:7842)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
2022-03-29 10:31:41.719 5792-5792/com.example.myapplication1 I/Process: Sending signal. PID: 5792 SIG: 9

Here is the link to the Youtube tutorial: Android Development for Beginners - Full Course - YouTube - the challenge is around the timestamp of the first hour into the tutorial.

I figured it out! Wrote mistakenly “txtEmail” instead of “edEmail” in line 29…

Any YouTube video for this…?

This looks like the reason.
Check the area around line number 29 of MainActivity.java file.

The link to the video :point_up_2:t4: