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author | mensonge <mensonge@b3834d28-1941-0410-a4f8-b48e95affb8f> | 2008-11-13 09:49:11 +0000 |
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committer | mensonge <mensonge@b3834d28-1941-0410-a4f8-b48e95affb8f> | 2008-11-13 09:49:11 +0000 |
commit | e44a7e37b6c7b5961adaffc62b9042b8d442938e (patch) | |
tree | 95b67c356e93163467db2451f2b8cce84ed5d582 /includes/js/dojo/back.js | |
parent | a62b9742ee5e28bcec6872d88f50f25b820914f6 (diff) | |
download | semanticscuttle-e44a7e37b6c7b5961adaffc62b9042b8d442938e.tar.gz semanticscuttle-e44a7e37b6c7b5961adaffc62b9042b8d442938e.tar.bz2 |
New feature: basic Ajax suggestion for tags and implementation of Dojo toolkit
git-svn-id: https://semanticscuttle.svn.sourceforge.net/svnroot/semanticscuttle/trunk@151 b3834d28-1941-0410-a4f8-b48e95affb8f
Diffstat (limited to 'includes/js/dojo/back.js')
-rw-r--r-- | includes/js/dojo/back.js | 394 |
1 files changed, 394 insertions, 0 deletions
diff --git a/includes/js/dojo/back.js b/includes/js/dojo/back.js new file mode 100644 index 0000000..3c62b82 --- /dev/null +++ b/includes/js/dojo/back.js @@ -0,0 +1,394 @@ +if(!dojo._hasResource["dojo.back"]){ //_hasResource checks added by build. Do not use _hasResource directly in your code. +dojo._hasResource["dojo.back"] = true; +dojo.provide("dojo.back"); + +/*===== +dojo.back = { + // summary: Browser history management resources +} +=====*/ + + +(function(){ + var back = dojo.back; + + // everyone deals with encoding the hash slightly differently + + function getHash(){ + var h = window.location.hash; + if(h.charAt(0) == "#"){ h = h.substring(1); } + return dojo.isMozilla ? h : decodeURIComponent(h); + } + + function setHash(h){ + if(!h){ h = ""; } + window.location.hash = encodeURIComponent(h); + historyCounter = history.length; + } + + // if we're in the test for these methods, expose them on dojo.back. ok'd with alex. + if(dojo.exists("tests.back-hash")){ + back.getHash = getHash; + back.setHash = setHash; + } + + var initialHref = (typeof(window) !== "undefined") ? window.location.href : ""; + var initialHash = (typeof(window) !== "undefined") ? getHash() : ""; + var initialState = null; + + var locationTimer = null; + var bookmarkAnchor = null; + var historyIframe = null; + var forwardStack = []; + var historyStack = []; + var moveForward = false; + var changingUrl = false; + var historyCounter; + + function handleBackButton(){ + //summary: private method. Do not call this directly. + + //The "current" page is always at the top of the history stack. + //console.debug("handlingBackButton"); + var current = historyStack.pop(); + if(!current){ return; } + var last = historyStack[historyStack.length-1]; + if(!last && historyStack.length == 0){ + last = initialState; + } + if(last){ + if(last.kwArgs["back"]){ + last.kwArgs["back"](); + }else if(last.kwArgs["backButton"]){ + last.kwArgs["backButton"](); + }else if(last.kwArgs["handle"]){ + last.kwArgs.handle("back"); + } + } + forwardStack.push(current); + //console.debug("done handling back"); + } + + back.goBack = handleBackButton; + + function handleForwardButton(){ + //summary: private method. Do not call this directly. + //console.debug("handling forward"); + var last = forwardStack.pop(); + if(!last){ return; } + if(last.kwArgs["forward"]){ + last.kwArgs.forward(); + }else if(last.kwArgs["forwardButton"]){ + last.kwArgs.forwardButton(); + }else if(last.kwArgs["handle"]){ + last.kwArgs.handle("forward"); + } + historyStack.push(last); + //console.debug("done handling forward"); + } + + back.goForward = handleForwardButton; + + function createState(url, args, hash){ + //summary: private method. Do not call this directly. + return {"url": url, "kwArgs": args, "urlHash": hash}; //Object + } + + function getUrlQuery(url){ + //summary: private method. Do not call this directly. + var segments = url.split("?"); + if(segments.length < 2){ + return null; //null + } + else{ + return segments[1]; //String + } + } + + function loadIframeHistory(){ + //summary: private method. Do not call this directly. + var url = (dojo.config["dojoIframeHistoryUrl"] || dojo.moduleUrl("dojo", "resources/iframe_history.html")) + "?" + (new Date()).getTime(); + moveForward = true; + if(historyIframe){ + dojo.isSafari ? historyIframe.location = url : window.frames[historyIframe.name].location = url; + }else{ + //console.warn("dojo.back: Not initialised. You need to call dojo.back.init() from a <script> block that lives inside the <body> tag."); + } + return url; //String + } + + function checkLocation(){ + //console.debug("checking url"); + if(!changingUrl){ + var hsl = historyStack.length; + + var hash = getHash(); + + if((hash === initialHash||window.location.href == initialHref)&&(hsl == 1)){ + // FIXME: could this ever be a forward button? + // we can't clear it because we still need to check for forwards. Ugg. + // clearInterval(this.locationTimer); + handleBackButton(); + return; + } + + // first check to see if we could have gone forward. We always halt on + // a no-hash item. + if(forwardStack.length > 0){ + if(forwardStack[forwardStack.length-1].urlHash === hash){ + handleForwardButton(); + return; + } + } + + // ok, that didn't work, try someplace back in the history stack + if((hsl >= 2)&&(historyStack[hsl-2])){ + if(historyStack[hsl-2].urlHash === hash){ + handleBackButton(); + return; + } + } + + if(dojo.isSafari && dojo.isSafari < 3){ + var hisLen = history.length; + if(hisLen > historyCounter) handleForwardButton(); + else if(hisLen < historyCounter) handleBackButton(); + historyCounter = hisLen; + } + } + //console.debug("done checking"); + }; + + back.init = function(){ + //summary: Initializes the undo stack. This must be called from a <script> + // block that lives inside the <body> tag to prevent bugs on IE. + if(dojo.byId("dj_history")){ return; } // prevent reinit + var src = dojo.config["dojoIframeHistoryUrl"] || dojo.moduleUrl("dojo", "resources/iframe_history.html"); + document.write('<iframe style="border:0;width:1px;height:1px;position:absolute;visibility:hidden;bottom:0;right:0;" name="dj_history" id="dj_history" src="' + src + '"></iframe>'); + }; + + back.setInitialState = function(/*Object*/args){ + //summary: + // Sets the state object and back callback for the very first page + // that is loaded. + //description: + // It is recommended that you call this method as part of an event + // listener that is registered via dojo.addOnLoad(). + //args: Object + // See the addToHistory() function for the list of valid args properties. + initialState = createState(initialHref, args, initialHash); + }; + + //FIXME: Make these doc comments not be awful. At least they're not wrong. + //FIXME: Would like to support arbitrary back/forward jumps. Have to rework iframeLoaded among other things. + //FIXME: is there a slight race condition in moz using change URL with the timer check and when + // the hash gets set? I think I have seen a back/forward call in quick succession, but not consistent. + + + /*===== + dojo.__backArgs = function(kwArgs){ + // back: Function? + // A function to be called when this state is reached via the user + // clicking the back button. + // forward: Function? + // Upon return to this state from the "back, forward" combination + // of navigation steps, this function will be called. Somewhat + // analgous to the semantic of an "onRedo" event handler. + // changeUrl: Boolean?|String? + // Boolean indicating whether or not to create a unique hash for + // this state. If a string is passed instead, it is used as the + // hash. + } + =====*/ + + back.addToHistory = function(/*dojo.__backArgs*/ args){ + // summary: + // adds a state object (args) to the history list. + // description: + // To support getting back button notifications, the object + // argument should implement a function called either "back", + // "backButton", or "handle". The string "back" will be passed as + // the first and only argument to this callback. + // + // To support getting forward button notifications, the object + // argument should implement a function called either "forward", + // "forwardButton", or "handle". The string "forward" will be + // passed as the first and only argument to this callback. + // + // If you want the browser location string to change, define "changeUrl" on the object. If the + // value of "changeUrl" is true, then a unique number will be appended to the URL as a fragment + // identifier (http://some.domain.com/path#uniquenumber). If it is any other value that does + // not evaluate to false, that value will be used as the fragment identifier. For example, + // if changeUrl: 'page1', then the URL will look like: http://some.domain.com/path#page1 + // + // example: + // | dojo.back.addToHistory({ + // | back: function(){ console.debug('back pressed'); }, + // | forward: function(){ console.debug('forward pressed'); }, + // | changeUrl: true + // | }); + + // BROWSER NOTES: + // Safari 1.2: + // back button "works" fine, however it's not possible to actually + // DETECT that you've moved backwards by inspecting window.location. + // Unless there is some other means of locating. + // FIXME: perhaps we can poll on history.length? + // Safari 2.0.3+ (and probably 1.3.2+): + // works fine, except when changeUrl is used. When changeUrl is used, + // Safari jumps all the way back to whatever page was shown before + // the page that uses dojo.undo.browser support. + // IE 5.5 SP2: + // back button behavior is macro. It does not move back to the + // previous hash value, but to the last full page load. This suggests + // that the iframe is the correct way to capture the back button in + // these cases. + // Don't test this page using local disk for MSIE. MSIE will not create + // a history list for iframe_history.html if served from a file: URL. + // The XML served back from the XHR tests will also not be properly + // created if served from local disk. Serve the test pages from a web + // server to test in that browser. + // IE 6.0: + // same behavior as IE 5.5 SP2 + // Firefox 1.0+: + // the back button will return us to the previous hash on the same + // page, thereby not requiring an iframe hack, although we do then + // need to run a timer to detect inter-page movement. + + //If addToHistory is called, then that means we prune the + //forward stack -- the user went back, then wanted to + //start a new forward path. + forwardStack = []; + + var hash = null; + var url = null; + if(!historyIframe){ + if(dojo.config["useXDomain"] && !dojo.config["dojoIframeHistoryUrl"]){ + console.debug("dojo.back: When using cross-domain Dojo builds," + + " please save iframe_history.html to your domain and set djConfig.dojoIframeHistoryUrl" + + " to the path on your domain to iframe_history.html"); + } + historyIframe = window.frames["dj_history"]; + } + if(!bookmarkAnchor){ + bookmarkAnchor = document.createElement("a"); + dojo.body().appendChild(bookmarkAnchor); + bookmarkAnchor.style.display = "none"; + } + if(args["changeUrl"]){ + hash = ""+ ((args["changeUrl"]!==true) ? args["changeUrl"] : (new Date()).getTime()); + + //If the current hash matches the new one, just replace the history object with + //this new one. It doesn't make sense to track different state objects for the same + //logical URL. This matches the browser behavior of only putting in one history + //item no matter how many times you click on the same #hash link, at least in Firefox + //and Safari, and there is no reliable way in those browsers to know if a #hash link + //has been clicked on multiple times. So making this the standard behavior in all browsers + //so that dojo.back's behavior is the same in all browsers. + if(historyStack.length == 0 && initialState.urlHash == hash){ + initialState = createState(url, args, hash); + return; + }else if(historyStack.length > 0 && historyStack[historyStack.length - 1].urlHash == hash){ + historyStack[historyStack.length - 1] = createState(url, args, hash); + return; + } + + changingUrl = true; + setTimeout(function() { + setHash(hash); + changingUrl = false; + }, 1); + bookmarkAnchor.href = hash; + + if(dojo.isIE){ + url = loadIframeHistory(); + + var oldCB = args["back"]||args["backButton"]||args["handle"]; + + //The function takes handleName as a parameter, in case the + //callback we are overriding was "handle". In that case, + //we will need to pass the handle name to handle. + var tcb = function(handleName){ + if(getHash() != ""){ + setTimeout(function() { setHash(hash); }, 1); + } + //Use apply to set "this" to args, and to try to avoid memory leaks. + oldCB.apply(this, [handleName]); + }; + + //Set interceptor function in the right place. + if(args["back"]){ + args.back = tcb; + }else if(args["backButton"]){ + args.backButton = tcb; + }else if(args["handle"]){ + args.handle = tcb; + } + + var oldFW = args["forward"]||args["forwardButton"]||args["handle"]; + + //The function takes handleName as a parameter, in case the + //callback we are overriding was "handle". In that case, + //we will need to pass the handle name to handle. + var tfw = function(handleName){ + if(getHash() != ""){ + setHash(hash); + } + if(oldFW){ // we might not actually have one + //Use apply to set "this" to args, and to try to avoid memory leaks. + oldFW.apply(this, [handleName]); + } + }; + + //Set interceptor function in the right place. + if(args["forward"]){ + args.forward = tfw; + }else if(args["forwardButton"]){ + args.forwardButton = tfw; + }else if(args["handle"]){ + args.handle = tfw; + } + + }else if(!dojo.isIE){ + // start the timer + if(!locationTimer){ + locationTimer = setInterval(checkLocation, 200); + } + + } + }else{ + url = loadIframeHistory(); + } + + historyStack.push(createState(url, args, hash)); + }; + + back._iframeLoaded = function(evt, ifrLoc){ + //summary: + // private method. Do not call this directly. + var query = getUrlQuery(ifrLoc.href); + if(query == null){ + // alert("iframeLoaded"); + // we hit the end of the history, so we should go back + if(historyStack.length == 1){ + handleBackButton(); + } + return; + } + if(moveForward){ + // we were expecting it, so it's not either a forward or backward movement + moveForward = false; + return; + } + + //Check the back stack first, since it is more likely. + //Note that only one step back or forward is supported. + if(historyStack.length >= 2 && query == getUrlQuery(historyStack[historyStack.length-2].url)){ + handleBackButton(); + }else if(forwardStack.length > 0 && query == getUrlQuery(forwardStack[forwardStack.length-1].url)){ + handleForwardButton(); + } + }; + })(); + +} |