[Android Studio] 구구단 출력하기

MainActivity6.java

package kr.co.aiai.app;

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 MainActivity6 extends AppCompatActivity {
    EditText et;
    TextView tv;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main6);

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

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

    }

    public void myclick(){
        String dan = et.getText()+"";
        int ddan = Integer.parseInt(dan);
        String text = "*****"+ddan+"단*****\n";
        for(int i=1; i<=9; i++){
            text += ddan + " * " + i + " = " + (ddan*i) + "\n";
        }
        tv.setText(text.toString());
    }




}

 

activity_main6.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
        android:gravity="center">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="horizontal">

            <TextView
                android:id="@+id/textView"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"

                android:text="출력 단 수 : "
                android:textSize="25dp" />

            <EditText
                android:id="@+id/et"
                android:layout_width="280dp"
                android:layout_height="wrap_content"

                android:ems="10"
                android:inputType="number" />
        </LinearLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"

            android:orientation="horizontal">

            <Button
                android:id="@+id/btn"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:text="출력하기" />

        </LinearLayout>

        <TextView
            android:id="@+id/tv"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:gravity="center"
            />


    </LinearLayout>

</androidx.constraintlayout.widget.ConstraintLayout>