ブラウザ側
var keypath = "switch" // DBʹswitchͱ͍͏໊લͰอଘ
var switchRef = firebase.database().ref(keypath);
var buttonState = null;
var button = document.getElementById("button");
button.addEventListener('click', function(){
switchRef.set(!buttonState); // ΫϦοΫ͞ΕͨΒOn/Offτάϧ
});
switchRef.on('value', function(sw) {
buttonState = sw.val(); // ͷมߋΛड͚औͬͨΒऔಘͯ͠දࣔΓସ͑
if (buttonState) {
button.innerHTML = '౮த';
button.style.background = "rgb(3,155,229)";
} else {
button.innerHTML = 'ফ౮த';
button.style.background = "rgb(155,155,155)";
}
});