How to make a rectangle with inverted rounded corners?

Based on: https://stackoverflow.com/a/36764393/1268507

Try with custom view:

public class CustomView extends View {
private Path mPath = new Path();

public CustomView(Context context) {
    super(context);
}

public CustomView(Context context, AttributeSet attrs) {
    super(context, attrs);
}

public CustomView(Context context, AttributeSet attrs, int defStyleAttr) {
    super(context, attrs, defStyleAttr);
}


@Override
protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);
    mPath.reset();
    mPath.addRoundRect(0, 0, getWidth(), getHeight(), 1000, 1000, Path.Direction.CW);
    mPath.setFillType(Path.FillType.INVERSE_EVEN_ODD);
    canvas.clipPath(mPath);
    canvas.drawColor(Color.parseColor("#FF0000"));
}
}

Not proper way, but will get the result, try

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item>
        <shape android:shape="rectangle">
            <padding
                android:bottom="-100dp"
                android:left="-100dp"
                android:right="-100dp"
                android:top="-100dp" />
        </shape>
    </item>
    <item>
        <shape android:shape="rectangle">
            <corners android:radius="200dp" />
            <stroke
                android:width="100dp"
                android:color="#FF0000" />
        </shape>
    </item>
</layer-list>