HTML5全屏,頁面可見性,訪問攝像頭和麥克風,檢測電池,預載入網頁功能
阿新 • • 發佈:2018-11-16
1,全屏
// 找到適合瀏覽器的全屏方法 function launchFullScreen(element) { if(element.requestFullScreen) { element.requestFullScreen(); } else if(element.mozRequestFullScreen) { element.mozRequestFullScreen(); } else if(element.webkitRequestFullScreen) { element.webkitRequestFullScreen(); } } // 啟動全屏模式 launchFullScreen(document.documentElement); // the whole page launchFullScreen(document.getElementById("videoElement")); // any individual element
2,頁面可見性:用來檢測頁面對於使用者的可見性,即返回使用者當前瀏覽的頁面或標籤的狀態變化。
// 設定隱藏屬性和可見改變事件的名稱,屬性需要加瀏覽器字首 // since some browsers only offer vendor-prefixed support var hidden, state, visibilityChange; if (typeof document.hidden !== "undefined") { hidden = "hidden"; visibilityChange = "visibilitychange"; state = "visibilityState"; } else if (typeof document.mozHidden !== "undefined") { hidden = "mozHidden"; visibilityChange = "mozvisibilitychange"; state = "mozVisibilityState"; } else if (typeof document.msHidden !== "undefined") { hidden = "msHidden"; visibilityChange = "msvisibilitychange"; state = "msVisibilityState"; } else if (typeof document.webkitHidden !== "undefined") { hidden = "webkitHidden"; visibilityChange = "webkitvisibilitychange"; state = "webkitVisibilityState"; } // 新增一個標題改變的監聽器 document.addEventListener(visibilityChange, function(e) { // 開始或停止狀態處理 }, false);
3,訪問攝像頭和麥克風
許Web應用程式訪問攝像頭和麥克風,而無需使用外掛。
// 設定事件監聽器 window.addEventListener("DOMContentLoaded", function() { // 獲取元素 var canvas = document.getElementById("canvas"), context = canvas.getContext("2d"), video = document.getElementById("video"), videoObj = { "video": true }, errBack = function(error) { console.log("Video capture error: ", error.code); }; // 設定video監聽器 if(navigator.getUserMedia) { // Standard navigator.getUserMedia(videoObj, function(stream) { video.src = stream; video.play(); }, errBack); } else if(navigator.webkitGetUserMedia) { // WebKit-prefixed navigator.webkitGetUserMedia(videoObj, function(stream){ video.src = window.webkitURL.createObjectURL(stream); video.play(); }, errBack); } }, false);
4,檢測電池:這是一個針對移動裝置應用程式的API,主要用於檢測裝置電池資訊。
var battery = navigator.battery || navigator.webkitBattery || navigator.mozBattery;
// 電池屬性
console.warn("Battery charging: ", battery.charging); // true
console.warn("Battery level: ", battery.level); // 0.58
console.warn("Battery discharging time: ", battery.dischargingTime);
// 新增事件監聽器
battery.addEventListener("chargingchange", function(e) {
console.warn("Battery charge change: ", battery.charging);
}, false);
5,預載入網頁內容,為瀏覽者提供一個平滑的瀏覽體驗
<!-- full page -->
<link rel="prefetch" href="http://davidwalsh.name/css-enhancements-user-experience" />
<!-- just an image -->
<link rel="prefetch" href="http://davidwalsh.name/wp-content/themes/walshbook3/images/sprite.png" />