How to create button in android

 Activity_main_xml : coding for layout

<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=".MainActivity">

    <Button
        android:id="@+id/button"
        android:layout_width="120dp"
        android:layout_height="120dp"
        android:text="Simple Button"
        tools:ignore="MissingConstraints"
         />

</androidx.constraintlayout.widget.ConstraintLayout>

MainActivity.java: Coding For MainActivity

package com.example.howtocreatebuttoninandroid;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    Button button; //Comments: Import Button Here

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        button=(Button) findViewById(R.id.button); //Comments: Call button from layout activitymain

        // Commnents: Set onclicklistener on your button
        // when you call something do by clicking the button
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                //This is Toast when you run your project and click on your button
                // it will call the toast and show you the "Hello Text"

                Toast.makeText(MainActivity.this,"Hello",Toast.LENGTH_SHORT).show();
            }
        });
    }
}



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