안드로이드 스튜디오 double 버튼만들기

 

 

package kr.co.aiai.app;

import android.os.Bundle;
import android.text.Editable;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

import androidx.appcompat.app.AppCompatActivity;

public class MainActivity2 extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);

        Button btn = (Button)findViewById(R.id.btn);
        EditText et = findViewById(R.id.et);


        btn.setOnClickListener(new View.OnClickListener(){
            @Override
            public void onClick(View view) {

                String a = et.getText().toString();
                int aa = Integer.parseInt(a);
                aa *= 2;
                et.setText(aa+"");
            }
        });


    }


}

누르면 2배가 된다