如何在Android Studio的Mainactivity中从对话框中进行反应？

import android.app.AlertDialog;
import android.content.DialogInterface;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

import androidx.appcompat.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity {

    private Button showDialogButton;

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

        showDialogButton = findViewById(R.id.show_dialog_button);
        showDialogButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                showCustomDialog();
            }
        });
    }

    private void showCustomDialog() {
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setTitle("提示");
        builder.setMessage("确定执行操作吗？");
        builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                // 在这里执行相应的操作
                Toast.makeText(MainActivity.this, "操作成功", Toast.LENGTH_SHORT).show();
            }
        });
        builder.setNegativeButton("取消", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                dialog.dismiss();
            }
        });
        AlertDialog dialog = builder.create();
        dialog.show();
    }
}