[RESOLVED] Keep getting ".. is not a constructor" – I don’t understand why.

@blue-eye-labsMar 23.2009

In trying to create a browser object (which parses XML data and displays it in a ‘Finder’-esque manner) I’ve stumbled across a problem which I’m unable to solve. When I was trying to test the object Firebug kept giving me “Browser is not a constructor”.
The code that called the object constructor is as follows:

[CODE] var b = new Browser(‘b’, ‘test’, ‘/runtime/browserdatacollections.php?sort=category’); [/CODE]

and the code for the actual constructor itself (I haven’t included any properties) is:

[CODE] function Browser(id, title, url) { /* Browser Object Creates a browsing GUI for browsing files/collections/artwork et cetera. Starts hidden. Properties id : object id, must be the same as the name given to the variable calling it. title : the title to be displayed (optional). url : the data feed url. Methods toggleWindow : shows/hides the window get_data : retrieves the data from the url specified. write_data : parses and writes the data to the browser window. open : performs all actions to open the browser window/display data. show : shows the browser window. hide : hides the browser window. */ this.id = id; this.title = title; this.url = url;

//Wrapper document.write(“<div id='” + this.id + “_wrapper’></div>)”); this.wrapper = $(‘wrapper’);

//Structure this.titlebar = document.createElement(“div”); this.titlebar.className = “browser_titlebar”; this.wrapper.appendChild(this.titlebar); this.titlebar.innerHTML = “<h1>” + this.title + “</h1>”;

this.browser = document.createElement(“div”); this.browser.className = “browser_browseWindow”; this.wrapper.appendChild(this.browser); } [/CODE]

Any help would be very much appreciated since this is an annoying obstacle.

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JavaScript

10 Comments(s) _↴

@trandrusMar 23.2009 — #works ok for me using ffpc 3.0.7 and firebug 1.3.3. have you checked other browsers or ff versions? sometimes firebug is firebuggy.

@blue-eye-labsauthorMar 23.2009 — #I get the same error using safari's debugger...

@blue-eye-labsauthorMar 23.2009 — #Maybe an error with previous code? The debuggers don't show any parse errors though...

@trandrusMar 23.2009 — #try using an anonymous function stored in a variable instead of a named function:

[CODE]
 var browser =  function(params) {
 
 //etc.
 
 }[/CODE]

or try a json approach:

[CODE]
 var app = {
 browser: function(params)
 {
 //etc.
 }
 };
 
 var useragent = new app.browser(params);[/CODE]

@blue-eye-labsauthorMar 23.2009 — #The thing is that all my other similarly scripted objects are done in the same way and don't give errors... For example:

[CODE]
 function Uploader(name, fdeck) {
 /*
 Uploader Object
 This creates a wrapper for handling the asynchronous upload of files.
 Properties
 nom : the object's name
 number : the number of the object if one is used in the name (so that the oncomplete function can be properly executed using an identification number).
 id : the unique id tag for the uploading portal.
 ulform : the upload form.
 url : where the form is sending the data.
 _STATINT : the status check number, used for clearing the interval for the check_status method.
 _STATSTR : the status string from the script.
 target : the target iframe used for portalling the upload.
 status : the object's status.
 oncomplete : can set an oncomplete function.
 icon : the "icon" used for displaying upload status.
 Methods:
 upload
 Initiates the file upload from a given file input node, filename and additional tags (for the runtime script).
 Usage: uploader.upload(HTML_INPUT_OBJ, String_Filename, Array_Add_tags)
 update_icon:
 Updates the icon for displaying progress.
 */
 this.nom = name;
 this.number = Number(name.match(/d/));
 this.id = "uploader_" + this.nom + "_" + (new Date).getTime();
 this.ulform = $(fdeck);
 this.url = this.ulform.action;
 this._STATINT = Number();
 this._STATSTR = String();
 this.target;
 this.status = 0;
 this.oncomplete;
 this.icon;
 
  this.target = document.createElement("iframe");
  this.target.id = this.target.name = this.id;
  this.target.style.width = this.target.style.height = "0px";
  this.target.style.border = "none";
  this.target.style.visibility = "none";
  this.target.src = "about:blank";
  this.target.contentEditable = true;
  document.body.appendChild(this.target);
 
  this.ulform.target = this.target.id; 
 }
 [/CODE]

@trandrusMar 23.2009 — #then i'd go through line by line and isolate the problem. its hard to tell with no context. document.write should be avoided since it's bound to the page load sequence. i'd also utilize more of the builtin jquery dom tools to simplify your procedure.

@blue-eye-labsauthorMar 23.2009 — #I'm not entirely sure what you mean. My js knowledge is a little patchy since it's not my main language.

@trandrusMar 23.2009 — #

[CODE]
 function Browser(id, title, url) { 
 /*
 this.id = id;
 this.title = title;
 this.url = url; 
 
  document.write("<div id='" + this.id + "_wrapper'></div>)");
  this.wrapper = $('wrapper');
 
   this.titlebar = document.createElement("div");
   this.titlebar.className = "browser_titlebar";
   this.wrapper.appendChild(this.titlebar);
   this.titlebar.innerHTML = "<h1>" + this.title + "</h1>";
 
   this.browser = document.createElement("div");
   this.browser.className = "browser_browseWindow";
   this.wrapper.appendChild(this.browser);	*/ 
 }
 [/CODE]

then run it and see if it errors. if not:

[CODE]
 function Browser(id, title, url) { 
 
   this.id = id;
  /*this.title = title;
  this.url = url; 
 
  document.write("<div id='" + this.id + "_wrapper'></div>)");
  this.wrapper = $('wrapper');
 
   this.titlebar = document.createElement("div");
   this.titlebar.className = "browser_titlebar";
   this.wrapper.appendChild(this.titlebar);
   this.titlebar.innerHTML = "<h1>" + this.title + "</h1>";
 
   this.browser = document.createElement("div");
   this.browser.className = "browser_browseWindow";
   this.wrapper.appendChild(this.browser);	*/ 
 }
 [/CODE]

etc. until you find the offending line. if you are instantiating this after the document loads, document.write might be causing the error. you also have an extra right paren:

document.write("<div id='" + this.id + "_wrapper'></div>)");

vs.

document.write("<div id='" + this.id + "_wrapper'></div>");

@blue-eye-labsauthorMar 24.2009 — #I tried commenting out the function body already. It still gives me "browser is not a constructor"... weird.

The reason I use document.write() by the way is so that I can insert the wrapper div (and everything else, subsequently) directly into the code [U]at that point[/U] in the page. It has worked in other functions, but I'm not sure why not this one.

I am curious about the mention of both json and jquery since I don't really know of them.

@blue-eye-labsauthorMar 24.2009 — #For some ridiculous reason it seems that changing the name of the function solves the problem! Ridiculous!

Before I mark this as "solved" however, I think I should test!

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