원형 프로그레스바

ㅇ res > drawable > circular_progressbar.xml

<?xml version="1.0" encoding="utf-8"?>
<rotate xmlns:android="http://schemas.android.com/apk/res/android"
    android:fromDegrees="270"
    android:pivotX="50%"
    android:pivotY="50%"
    android:toDegrees="270">

    <shape
        android:innerRadiusRatio="2.5"
        android:shape="ring"
        android:thickness="2dp"
        android:useLevel="true"><!-- this line fixes the issue for lollipop api 21 -->

        <gradient
            android:angle="0"
            android:endColor="@color/colorPrimary"
            android:startColor="@color/colorPrimary"
            android:type="sweep"
            android:useLevel="false"/>
    </shape>

</rotate>

ㅇ res > drawable > circle_shape.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="ring"
    android:innerRadiusRatio="2.5"
    android:thickness="2dp"
    android:useLevel="false">

    <solid android:color="#FFFFFF" />
</shape>

ㅇ res > layout > layout_main.xml

<ProgressBar
    android:id="@+id/progress_bar"
    android:layout_width="60dp"
    android:layout_height="60dp"
    android:layout_gravity="center"
    android:progressDrawable="@drawable/circular_progressbar"
    android:indeterminateDrawable="@drawable/circular_progressbar"
    android:background="@drawable/circle_shape"
    android:indeterminate="false"
    android:max="100"
    android:visibility="gone"/>

ㅇ MainActivity.java

private ProgressBar mProgress_bar;

private ObjectAnimator mObjectAnimator;

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

    mProgress_bar = (ProgressBar) findViewById(R.id.progress_bar);

}

void showProgressBar(){
    mProgress_bar.setVisibility(View.VISIBLE);

    final int FIRST = 0, MAX = mProgress_bar.getMax(), DURATION = 3000;
    mProgress_bar.setProgress(0);
    mProgress_bar.post(new Runnable() {
        @Override
        public void run() {
            for(int i=0; i<=MAX; i++){
                mProgress_bar.setProgress(i);
            }
        }
    });

    if(mObjectAnimator == null) mObjectAnimator = ObjectAnimator.ofInt(mProgress_bar, "progress", FIRST, MAX);
    mObjectAnimator.setDuration(DURATION);
    mObjectAnimator.setInterpolator(new DecelerateInterpolator());
    mObjectAnimator.start();
}

void hideProgressBar(){
    if(mObjectAnimator != null && mObjectAnimator.isRunning()) mObjectAnimator.end();
    mProgress_bar.setVisibility(View.GONE);
}