안드로이드 스튜디오 구구단

package kr.co.aiai.app;

import android.os.Bundle;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

import androidx.appcompat.app.AppCompatActivity;

public class MainActivity3 extends AppCompatActivity {

    EditText et;
    TextView tvv;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main3);

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

        btn.setOnClickListener(view -> {
            myclick();

        });
    }

    public void myclick(){
        String a = et.getText().toString();
        int aa = Integer.parseInt(a);

        String code ="";
        for(int i = 1; i<=9; i++){
            code+= aa+"*"+i+"="+(aa*i)+"\n";
        }

        tvv.setText(code);
    }
}

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