CheckBox ch1, ch2, ch3, ch4; ch1 = findViewById(R.id.checkBox1); ch2 = findViewById(R.id.checkBox2); ch3 = findViewById(R.id.checkBox3); ch4 = findViewById(R.id ...

import android.widget.CheckBox; import android.widget.Toast; public class MainActivity extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { ...