I am not able to draw the circle using Custom Views in Android. It just doesn't work, even though it is a basic code implementation, it is not working. Can someone help me for the same?
This is Custom View class implementation:
public class CustomView extends View {
    private Paint paint;
    private int color;
    private float radius;
    public CustomView(Context context) {
        super(context);
        init();
    }
    public CustomView(Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
        TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.CustomView);      
        color = ta.getColor(R.styleable.CustomView_circleColor, Color.BLACK);
        radius = ta.getFloat(R.styleable.CustomView_circleSize, 200f);
        ta.recycle();
        init();
    }
    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        canvas.drawCircle(getWidth() / 2, getHeight() / 2, radius, paint);
    }
    private void init() {
        paint = new Paint();
        paint.setColor(color);
    }
    public CustomView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }
}
And this is my MainActivity implementation:
  public class MainActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
This is attr.xml file:
    <?xml version="1.0" encoding="utf-8"?>
<resources>
    <declare-styleable name="CustomView">
        <attr name="circleColor" format="color"></attr>
        <attr name="circleSize" format="enum">
            <enum name="small" value="100"></enum>
            <enum name="medium" value="300"></enum>
            <enum name="large" value="600"></enum>
        </attr>
    </declare-styleable>
</resources>
And this is activity_main.xml file:
    <?xml version="1.0" encoding="utf-8"?>
<FrameLayout 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="com.hp.customviews.MainActivity">
    <com.hp.customviews.CustomView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:circleColor="#009688"
        app:circleSize="medium"
        android:visibility="gone" />
</FrameLayout>
What am I doing wrong? Why my code is not working? Please help me with this.
