diff options
Diffstat (limited to 'src/www/TransQuiz/support.js')
| -rw-r--r-- | src/www/TransQuiz/support.js | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/src/www/TransQuiz/support.js b/src/www/TransQuiz/support.js new file mode 100644 index 000000000..562bab96a --- /dev/null +++ b/src/www/TransQuiz/support.js @@ -0,0 +1,285 @@ +/* --- Accessing document elements ------------------------------------------ */ + +function element(id) { + return document.getElementById(id); +} + +/* --- JavaScript tricks ---------------------------------------------------- */ + +// To be able to object methods that refer to "this" as callbacks +// See section 3.3 of https://github.com/spencertipping/js-in-ten-minutes/raw/master/js-in-ten-minutes.pdf +function bind(f, this_value) { + return function () {return f.apply (this_value, arguments)}; +}; + +/* --- JSONP ---------------------------------------------------------------- */ + +// Inspired by the function jsonp from +// http://www.west-wind.com/Weblog/posts/107136.aspx +// See also http://niryariv.wordpress.com/2009/05/05/jsonp-quickly/ +// http://en.wikipedia.org/wiki/JSON#JSONP +function jsonp(url,callback) +{ + if (url.indexOf("?") > -1) + url += "&jsonp=" + else + url += "?jsonp=" + url += callback; + //url += "&" + new Date().getTime().toString(); // prevent caching + + var script = empty("script"); + script.setAttribute("src",url); + script.setAttribute("type","text/javascript"); + document.body.appendChild(script); +} + +var json = {next:0}; + +// Like jsonp, but instead of passing the name of the ballback function, you +// pass the callback function directly, making it possible to use anonymous +// functions. +function jsonpf(url,callback) +{ + var name="callback"+(json.next++); + json[name]=function(x) { delete json[name]; callback(x); } + jsonp(url,"json."+name); +} + +/* --- AJAX ----------------------------------------------------------------- */ + +function GetXmlHttpObject(handler) +{ + var objXMLHttp=null + if (window.XMLHttpRequest) + { + objXMLHttp=new XMLHttpRequest() + } + else if (window.ActiveXObject) + { + objXMLHttp=new ActiveXObject("Microsoft.XMLHTTP") + } + return objXMLHttp +} + +function ajax_http_get(url,callback) { + var http=GetXmlHttpObject() + if (http==null) { + alert ("Browser does not support HTTP Request") + return + } + var statechange=function() { + if (http.readyState==4 || http.readyState=="complete") { + if(http.status==200) callback(http.responseText); + else alert("Request for "+url+" failed: " + +http.status+" "+http.statusText); + } + } + http.onreadystatechange=statechange; + http.open("GET",url,true) + http.send(null) + //dump("http get "+url+"\n") + return http +} + +// JSON via AJAX +function ajax_http_get_json(url,cont) { + ajax_http_get(url,function(txt) { cont(eval("("+txt+")")); }); +} + +function sameOrigin(url) { + return hasPrefix(url,location.protocol+"//"+location.host+"/"); +} + +// Use AJAX when possible, fallback to JSONP +function http_get_json(url,cont) { + if(sameOrigin(url)) ajax_http_get_json(url,cont); + else jsonpf(url,cont); +} + + +/* --- HTML construction ---------------------------------------------------- */ +function text(s) { return document.createTextNode(s); } + +function node(tag,as,ds) { + var n=document.createElement(tag); + for(var a in as) n.setAttribute(a,as[a]); + for(var i in ds) n.appendChild(ds[i]); + return n; +} + +function empty(tag,name,value) { + var el=node(tag,{},[]) + if(name && value) el.setAttribute(name,value); + return el; +} + +function empty_id(tag,id) { return empty(tag,"id",id); } +function empty_class(tag,cls) { return empty(tag,"class",cls); } + +function div_id(id) { return empty_id("div",id); } +function span_id(id) { return empty_id("span",id); } + +function wrap(tag,contents) { return node(tag,{},[contents]); } + +function wrap_class(tag,cls,contents) { + var el=empty_class(tag,cls); + if(contents) el.appendChild(contents); + return el; +} + +function span_class(cls,contents) { return wrap_class("span",cls,contents); } +function div_class(cls,contents) { return wrap_class("div",cls,contents); } + +function p(contents) { return wrap("p",contents); } +function dt(contents) { return wrap("dt",contents); } +function li(contents) { return wrap("li",contents); } + +function th(contents) { return wrap("th",contents); } +function td(contents) { return wrap("td",contents); } + +function tr(cells) { return node("tr",{},cells); } + +//modified for quiz (id added) +function button(label,action,key ,id) { + var el=node("input",{"type":"button","value":label},[]); + if(typeof action=="string") el.setAttribute("onclick",action); + else el.onclick=action; + if(key) el.setAttribute("accesskey",key); + if(id) el.setAttribute("id",id); + return el; +} + +//added for quiz +function submit_button(label, id) { + var el=empty("input","type","submit"); + el.setAttribute("value",label); + if(id) el.setAttribute("id", id); + return el; +} + +function option(label,value) { + return node("option",{"value":value},[text(label)]); +} + +function appendChildren(el,ds) { + for(var i in ds) el.appendChild(ds[i]); + return el; +} + +function insertFirst(parent,child) { + parent.insertBefore(child,parent.firstChild); +} + +function tda(cs) { return node("td",{},cs); } + +function img(src) { return empty("img","src",src); } + +/* --- Debug ---------------------------------------------------------------- */ + +function debug(s) { + var d=element("debug"); + if(d) d.appendChild(text(s+"\n")) +} + +function show_props(obj, objName) { + var result = ""; + for (var i in obj) { + result += objName + "." + i + " = " + obj[i] + "<br>"; + } + return result; +} + +function field_names(obj) { + var result = ""; + for (var i in obj) { + result += " " + i; + } + return result; +} + +/* --- Data manipulation ---------------------------------------------------- */ +function swap(a,i,j) { // Note: this doesn't work on strings. + var tmp=a[i]; + a[i]=a[j]; + a[j]=tmp; + return a; +} + +function sort(a) { +// https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Global_Objects/Array/sort + return a.sort(); + /* // Note: this doesn't work on strings. + for(var i=0;i<a.length-1;i++) { + var min=i; + for(var j=i+1;j<a.length;j++) + if(a[j]<a[min]) min=j; + if(min!=i) swap(a,i,min); + } + return a; + */ +} + +function filter(p,xs) { + var ys=[]; + for(var i=0;i<xs.length;i++) + if(p(xs[i])) ys[ys.length]=xs[i]; + return ys; +} + +function implode(cs) { // array of strings to string + /* + var s=""; + for(var i=0;i<cs.length;i++) + s+=cs[i]; + return s; + */ + return cs.join(""); +} + +function hasPrefix(s,pre) { return s.substr(0,pre.length)==pre; } + +function commonPrefix(s1,s2) { + for(var i=0;i<s1.length && i<s2.length && s1[i]==s2[i];i++); + return s1.substr(0,i); +} + +/* +function all(p,xs) { + for(var i=0;i<xs.length;i++) + if(!p(xs[i])) return false; + return true; +} +*/ + +function map(f,xs) { + var ys=[]; + for(var i=0;i<xs.length;i++) ys[i]=f(xs[i]); + return ys; +} + +// map in continuation passing style +function mapc(f,xs,cont) { mapc_from(f,xs,0,[],cont); } + +function mapc_from(f,xs,i,ys,cont) { + if(i<xs.length) + f(xs[i],function(y){ys[i]=y;mapc_from(f,xs,i+1,ys,cont)}); + else + cont(ys); +} + +function overlaps(as,bs) { + for(var i=0;i<as.length;i++) + if(elem(as[i],bs)) return true; + return false; +} + +function elem(a,as) { + for(var i=0;i<as.length;i++) + if(a==as[i]) return true; + return false; +} + +function shuffle(a) { + for(i=0;i<a.length;i++) swap(a,i,Math.floor(Math.random()*a.length)) + return a; +} |
