Multiple CheckBoxes in Android

activity_main.xml
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<LinearLayout 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=".MainActivity"
    android:orientation="vertical"
    android:id="@+id/hello">


    <CheckBox
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="CheckBox1"
        android:id="@+id/checkBox"
        android:layout_gravity="center_horizontal"
        android:checked="false"
        android:layout_marginTop="15dp" />

    <CheckBox
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="CheckBox2"
        android:id="@+id/checkBox2"
        android:layout_gravity="center_horizontal"
        android:checked="false"
        android:layout_marginTop="15dp" />

    <CheckBox
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="CheckBox3"
        android:id="@+id/checkBox3"
        android:layout_gravity="center_horizontal"
        android:checked="false"
        android:layout_marginTop="15dp" />

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Show"
        android:id="@+id/button"
        android:layout_gravity="center_horizontal"
        android:layout_marginTop="35dp" />
</LinearLayout>

MainActivity.java

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package com.android.anil.multiplecheckboxes;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {
    CheckBox c1,c2,c3;
    Button b1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        c1=(CheckBox)findViewById(R.id.checkBox);
        c2=(CheckBox)findViewById(R.id.checkBox2);
        c3=(CheckBox)findViewById(R.id.checkBox3);
        b1=(Button)findViewById(R.id.button);
        b1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if(c1.isChecked()){
                    Toast.makeText(getApplicationContext(),"CheckBox1 is Checked",5000).show();
                }else{
                    Toast.makeText(getApplicationContext(),"CheckBox1 is UnChecked",5000).show();

                }

                if(c2.isChecked()){
                    Toast.makeText(getApplicationContext(),"CheckBox2 is Checked",5000).show();
                }else{
                    Toast.makeText(getApplicationContext(),"CheckBox2 is UnChecked",5000).show();

                }

                if(c3.isChecked()){
                    Toast.makeText(getApplicationContext(),"CheckBox3 is Checked",5000).show();
                }else{
                    Toast.makeText(getApplicationContext(),"CheckBox3 is UnChecked",5000).show();

                }
            }
        });
    }

}

Output is:

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