class MainActivity

package kr.co.braverokmc.mygraphanimation;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.ProgressBar;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    Animation grow;
    ProgressBar progressBar;

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


        progressBar=(ProgressBar)findViewById(R.id.progress1);

        grow= AnimationUtils.loadAnimation(getApplicationContext(), R.anim.grow);
        progressBar.setAnimation(grow);

    }


    //모든 액티비티가 초기화 과정후 시작되는 메소드
    @Override
    public void onWindowFocusChanged(boolean hasFocus) {
        super.onWindowFocusChanged(hasFocus);

        Toast.makeText(getApplicationContext() ,
                "onWindowFocusChanged 호출됨 : " + hasFocus ,Toast.LENGTH_SHORT).show();
        if(hasFocus){
            grow.start();
        }else{
            grow.reset();
        }

    }



}

 

 

 

R.layout.activity_main

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:id="@+id/line1">


        <TextView
            android:id="@+id/text1"
            android:layout_width="wrap_content"
            android:layout_height="48dp"
            android:text="사과"
            android:textSize="30dp"
            android:layout_marginLeft="5dp"
            android:layout_marginRight="5dp"

            />

        <ProgressBar
            style="?android:attr/progressBarStyleHorizontal"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:id="@+id/progress1"
            android:layout_weight="1"
            android:layout_gravity="center_horizontal|center_vertical"
            />




    </LinearLayout>


</LinearLayout>

 

 

grow.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">

    <scale
            android:fromXScale="0.0"
            android:fromYScale="1.0"
            android:toXScale="1.0"
            android:toYScale="1.0"
            android:pivotX="0%p"
            android:pivotY="50%p"
            android:duration="10000"

        />



</set>