history.js

flex平台下的red5流媒体播放器

BrowserHistoryUtils = {
    addEvent: function(elm, evType, fn, useCapture) {
        useCapture = useCapture || false;
        if (elm.addEventListener) {
            elm.addEventListener(evType, fn, useCapture);
            return true;
        }
        else if (elm.attachEvent) {
            var r = elm.attachEvent('on' + evType, fn);
            return r;
        }
        else {
            elm['on' + evType] = fn;
        }
    }
}

BrowserHistory = (function() {
    // type of browser
    var browser = {
        ie: false, 
        firefox: false, 
        safari: false, 
        opera: false, 
        version: -1
    };

    // if setDefaultURL has been called, our first clue
    // that the SWF is ready and listening
    //var swfReady = false;

    // the URL we'll send to the SWF once it is ready
    //var pendingURL = '';

    // Default app state URL to use when no fragment ID present
    var defaultHash = '';

    // Last-known app state URL
    var currentHref = document.location.href;

    // Initial URL (used only by IE)
    var initialHref = document.location.href;

    // Initial URL (used only by IE)
    var initialHash = document.location.hash;

    // History frame source URL prefix (used only by IE)
    var historyFrameSourcePrefix = 'history/historyFrame.html?';

    // History maintenance (used only by Safari)
    var currentHistoryLength = -1;

    var historyHash = [];

    var initialState = createState(initialHref, initialHref + '#' + initialHash, initialHash);

    var backStack = [];
    var forwardStack = [];

    var currentObjectId = null;

    //UserAgent detection
    var useragent = navigator.userAgent.toLowerCase();

    if (useragent.indexOf("opera") != -1) {
        browser.opera = true;
    } else if (useragent.indexOf("msie") != -1) {
        browser.ie = true;
        browser.version = parseFloat(useragent.substring(useragent.indexOf('msie') + 4));
    } else if (useragent.indexOf("safari") != -1) {
        browser.safari = true;
        browser.version = parseFloat(useragent.substring(useragent.indexOf('safari') + 7));
    } else if (useragent.indexOf("gecko") != -1) {
        browser.firefox = true;
    }

    if (browser.ie == true && browser.version == 7) {
        window["_ie_firstload"] = false;
    }

    // Accessor functions for obtaining specific elements of the page.
    function getHistoryFrame()
    {
        return document.getElementById('ie_historyFrame');
    }

    function getAnchorElement()
    {
        return document.getElementById('firefox_anchorDiv');
    }

    function getFormElement()
    {
        return document.getElementById('safari_formDiv');
    }

    function getRememberElement()
    {
        return document.getElementById("safari_remember_field");
    }

    // Get the Flash player object for performing ExternalInterface callbacks.
    // Updated for changes to SWFObject2.
    function getPlayer(id) {
		if (id && document.getElementById(id)) {
			var r = document.getElementById(id);
			if (typeof r.SetVariable != "undefined") {
				return r;
			}
			else {
				var o = r.getElementsByTagName("object");
				var e = r.getElementsByTagName("embed");
				if (o.length > 0 && typeof o[0].SetVariable != "undefined") {
					return o[0];
				}
				else if (e.length > 0 && typeof e[0].SetVariable != "undefined") {
					return e[0];
				}
			}
		}
		else {
			var o = document.getElementsByTagName("object");
			var e = document.getElementsByTagName("embed");
			if (e.length > 0 && typeof e[0].SetVariable != "undefined") {
				return e[0];
			}
			else if (o.length > 0 && typeof o[0].SetVariable != "undefined") {
				return o[0];
			}
			else if (o.length > 1 && typeof o[1].SetVariable != "undefined") {
				return o[1];
			}
		}
		return undefined;
	}
    
    function getPlayers() {
        var players = [];
        if (players.length == 0) {
            var tmp = document.getElementsByTagName('object');
            players = tmp;
        }
        
        if (players.length == 0 || players[0].object == null) {
            var tmp = document.getElementsByTagName('embed');
            players = tmp;
        }
        return players;
    }

	function getIframeHash() {
		var doc = getHistoryFrame().contentWindow.document;
		var hash = String(doc.location.search);
		if (hash.length == 1 && hash.charAt(0) == "?") {
			hash = "";
		}
		else if (hash.length >= 2 && hash.charAt(0) == "?") {
			hash = hash.substring(1);
		}
		return hash;
	}

    /* Get the current location hash excluding the '#' symbol. */
    function getHash() {
       // It would be nice if we could use document.location.hash here,
       // but it's faulty sometimes.
       var idx = document.location.href.indexOf('#');
       return (idx >= 0) ? document.location.href.substr(idx+1) : '';
    }

    /* Get the current location hash excluding the '#' symbol. */
    function setHash(hash) {
       // It would be nice if we could use document.location.hash here,
       // but it's faulty sometimes.
       if (hash == '') hash = '#'
       document.location.hash = hash;
    }

    function createState(baseUrl, newUrl, flexAppUrl) {
        return { 'baseUrl': baseUrl, 'newUrl': newUrl, 'flexAppUrl': flexAppUrl, 'title': null };
    }

    /* Add a history entry to the browser.
     *   baseUrl: the portion of the location prior to the '#'
     *   newUrl: the entire new URL, including '#' and following fragment
     *   flexAppUrl: the portion of the location following the '#' only
     */
    function addHistoryEntry(baseUrl, newUrl, flexAppUrl) {

        //delete all the history entries
        forwardStack = [];

        if (browser.ie) {
            //Check to see if we are being asked to do a navigate for the first
            //history entry, and if so ignore, because it's coming from the creation
            //of the history iframe
            if (flexAppUrl == defaultHash && document.location.href == initialHref && window['_ie_firstload']) {
                currentHref = initialHref;
                return;
            }
            if ((!flexAppUrl || flexAppUrl == defaultHash) && window['_ie_firstload']) {
                newUrl = baseUrl + '#' + defaultHash;
                flexAppUrl = defaultHash;
            } else {
                // for IE, tell the history frame to go somewhere without a '#'
                // in order to get this entry into the browser history.
                getHistoryFrame().src = historyFrameSourcePrefix + flexAppUrl;
            }
            setHash(flexAppUrl);
        } else {

            //ADR
            if (backStack.length == 0 && initialState.flexAppUrl == flexAppUrl) {
                initialState = createState(baseUrl, newUrl, flexAppUrl);
            } else if(backStack.length > 0 && backStack[backStack.length - 1].flexAppUrl == flexAppUrl) {
                backStack[backStack.length - 1] = createState(baseUrl, newUrl, flexAppUrl);
            }

            if (browser.safari) {
                // for Safari, submit a form whose action points to the desired URL
                if (browser.version <= 419.3) {
                    var file = window.location.pathname.toString();
                    file = file.substring(file.lastIndexOf("/")+1);
                    getFormElement().innerHTML = '<form name="historyForm" action="'+file+'#' + flexAppUrl + '" method="GET"></form>';
                    //get the current elements and add them to the form
                    var qs = window.location.search.substring(1);
                    var qs_arr = qs.split("&");
                    for (var i = 0; i < qs_arr.length; i++) {
                        var tmp = qs_arr[i].split("=");
                        var elem = document.createElement("input");
                        elem.type = "hidden";
                        elem.name = tmp[0];
                        elem.value = tmp[1];
                        document.forms.historyForm.appendChild(elem);
                    }
                    document.forms.historyForm.submit();
                } else {
                    top.location.hash = flexAppUrl;
                }
                // We also have to maintain the history by hand for Safari
                historyHash[history.length] = flexAppUrl;
                _storeStates();
            } else {
                // Otherwise, write an anchor into the page and tell the browser to go there
                addAnchor(flexAppUrl);
                setHash(flexAppUrl);
            }
        }
        backStack.push(createState(baseUrl, newUrl, flexAppUrl));
    }

    function _storeStates() {
        if (browser.safari) {
            getRememberElement().value = historyHash.join(",");
        }
    }

    function handleBackButton() {
        //The "current" page is always at the top of the history stack.
        var current = backStack.pop();
        if (!current) { return; }
        var last = backStack[backStack.length - 1];
        if (!last && backStack.length == 0){
            last = initialState;
        }
        forwardStack.push(current);
    }

    function handleForwardButton() {
        //summary: private method. Do not call this directly.

        var last = forwardStack.pop();
        if (!last) { return; }
        backStack.push(last);
    }

    function handleArbitraryUrl() {
        //delete all the history entries
        forwardStack = [];
    }

    /* Called periodically to poll to see if we need to detect navigation that has occurred */
    function checkForUrlChange() {

        if (browser.ie) {
            if (currentHref != document.location.href && currentHref + '#' != document.location.href) {
                //This occurs when the user has navigated to a specific URL
                //within the app, and didn't use browser back/forward
                //IE seems to have a bug where it stops updating the URL it
                //shows the end-user at this point, but programatically it
                //appears to be correct.  Do a full app reload to get around
                //this issue.
                if (browser.version < 7) {
                    currentHref = document.location.href;
                    document.location.reload();
                } else {
					if (getHash() != getIframeHash()) {
						// this.iframe.src = this.blankURL + hash;
						var sourceToSet = historyFrameSourcePrefix + getHash();
						getHistoryFrame().src = sourceToSet;
					}
                }
            }
        }

        if (browser.safari) {
            // For Safari, we have to check to see if history.length changed.
            if (currentHistoryLength >= 0 && history.length != currentHistoryLength) {
                //alert("did change: " + history.length + ", " + historyHash.length + "|" + historyHash[history.length] + "|>" + historyHash.join("|"));
                // If it did change, then we have to look the old state up
                // in our hand-maintained array since document.location.hash
                // won't have changed, then call back into BrowserManager.
                currentHistoryLength = history.length;
                var flexAppUrl = historyHash[currentHistoryLength];
                if (flexAppUrl == '') {
                    //flexAppUrl = defaultHash;
                }
                //ADR: to fix multiple
                if (typeof BrowserHistory_multiple != "undefined" && BrowserHistory_multiple == true) {
                    var pl = getPlayers();
                    for (var i = 0; i < pl.length; i++) {
                        pl[i].browserURLChange(flexAppUrl);
                    }
                } else {
                    getPlayer().browserURLChange(flexAppUrl);
                }
                _storeStates();
            }
        }
        if (browser.firefox) {
            if (currentHref != document.location.href) {
                var bsl = backStack.length;