var w = floaty.rawWindow(
<frame gravity="center" bg="file:///sdcard/clip.png" alpha="1" />
);

w.setSize(540, 100);
w.setTouchable(false);
w.setPosition(0,200)
setTimeout(()=>{}, 60000);
已经新建了一个悬浮窗,请教如何设置alpha的值