Untitled

package com.example.kiranproj1;

import android.os.Bundle;
import android.view.View;

import androidx.activity.EdgeToEdge;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.graphics.Insets;
import androidx.core.view.ViewCompat;
import androidx.core.view.WindowInsetsCompat;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button b1=findViewById(R.id.button);
        b1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(getApplicationContext(), "Hello World", Toast.LENGTH_SHORT).show();
        });
    }
}

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package com.example.kiranproj2;

import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import androidx.appcompat.app.AppCompatActivity;


public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        EditText ed1, ed2;
        TextView tv;
        Button b;

        ed1 = findViewById(R.id.editTextText2);
        ed2 = findViewById(R.id.editTextText3);
        tv = findViewById(R.id.textView4);
        b = findViewById(R.id.button);

        b.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                int a = Integer.parseInt(ed1.getText().toString());
                int b = Integer.parseInt(ed2.getText().toString());
                int sum = a + b;
                tv.setText("sum=" + sum);
            }
        });
        {

        }
    }}

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package com.example.kiranproj3;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import androidx.appcompat.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button b = findViewById(R.id.button);
        EditText ed = findViewById(R.id.editTextText);
        TextView tv = findViewById(R.id.textView);
        b.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                tv.setText(ed.getText().toString());
            }
        });
    }
}