JavaScript - Cloning Object And I Can't Override Properties, Why?
I have something like this
var oneTest = new CustomObj({ prop1 : 'value1', prop2 : 'value2', prop3 : 'value3' }) var twoText = Object.clone(oneTest) twoText.prop2 = "newvalue2" And when I console log twoText I see something like +Data prop2 Inside Data is a prop2 that has the value of "value2". THAT is the one I want to change/override... yet the console shows me that the prop2 is outside of the data structure so when I am acting on the cloned obj I am not getting the results i need. I tried obj.extend etc.... and that didn't work, perhaps my syntax was wrong. Any advice? Similar TutorialsI created a method for displaying an object's properties: Code: renderfunction = false; function showProperty (object, property) { document.write ('<td class="type">' + (typeof object[property]) + '</td>' + '<td class="name">' + property + '</td>'); document.writeln('<td class="value">' + ( (typeof object[property] != 'function') ? object[property] :( (property != 'showProperties') ? ( renderfunction ? object[property]() : ('<span class="self">NOT RENDERED</span>') ) : ('<span class="self">THIS</span>') ) ) + '</td>'); document.writeln('<td class="hasOwnProperty" >' + ( object.hasOwnProperty(property) ? "Local" : "Inherited" ) + '</td>'); if (typeof object[property] == 'function') { document.writeln ('<td class="function">' + object[property] + '</td>'); } else { document.writeln ('<td class="function"> </td>'); } } As long as renderfunction = false, the object is fine coming out of this function. However, if I change renderfunction to true, all my properties become undefined. Why isn't this working as I expect it to? How should I fix it? Thanks in advance, -Brian. Hi all, I was looking at mozilla object.watch function and found this post http://stackoverflow.com/questions/1...r-all-browsers and the solution post has a object.watch function, my question is how is this implemented? Do I need to put it in a file and include it along with my other libs? When I call it do I need to add the .prototype or just PHP Code: myObject.watch("itemSelect", handler); Will this create a problem if I'm using mozilla? Thanks! I'm not sure I phrased the question properly and it's probably easiest to show what I'm trying to get. Basically, I want to find all the properties(?) available for a single track object in iTunes. For example, this is how I access what's stored as the Album and Artist for a track: Code: var myTracks = myPlaylists(1).Tracks; alert(myTracks(1).Album); alert(myTracks(1).Artist); There are a ton of properties (like Album and Artist), but I don't know what they all are, so I was trying to list them like this, but it doesn't work: Code: for(var key in myTracks(1)) alert(key); It's probably obvious why this doesn't work, but does anyone know how to get this list? Thanks for any help! Do many programmers remember most of the object properties and methods or do they use IDE or references to find those specific objects. I'm starting to learn Javascript and seeing all the different type of objects available can be depressing. Hello everyone, I am fairly familiar with the concept of Objects and their properties and methods, but javascript being object based as opposed to object oriented has me stumped on how to access an object's properties from an onclick event handler created for another object created within the original object. In the example below, I have a constructor function called anyObj. to which I pass an object reference to an element. anyObj has 3 properties and one function increaseWidth() increaseWidth() creates a new button with an onclick event handler and this is where I have a problem. The onclick function needs to increase the value of anyObj's this.width property. I originally had a line this.width += 10; in the onclick but quickly realised why this wasn't working because the this in the onclick function refers to the new button object and not the this.width property of anyObj. The workaround I have used, and it works, is to make a copy of all the this.xxxxx properties. eg. width = this.width; and use the width variable in the onclick as you can see below. This "workaround" works fine but doesn't feel ideal to me. So, what I am asking advice on is, is there a better way to access the anyObj()'s properties from within the onclick function than the way I have done it? Obviously I would prefer to not have to make copies of all the anyObj() properties like I have to make them accessible to the onclick function. Code: function anyObj(divObj){ this.elem = divObj; this.width = 50; this.height = 50; this.increaseWidth=function(){ width = this.width; height = this.height; //create a button for this object to be appended to an element later on var newButton = document.createElement('button'); newButton.onclick=function(){ width += 10; //... //... } //... //... } } Hey everyone, I'm a newbie writing a tic tac toe program using OOP. It was simple setting it up so that a player could click on a box to put an X or an O there, but I've run into serious issues when trying to make it so a player couldn't overwrite the AI's choice and the AI couldn't overwrite the player's. An example of this would be if I made the top right box an X and the AI then made the center box an O, and then I accidentally clicked the center box and made it into an X. I want to prevent that. Every box on the grid is an object with the property of "taken" that helps the program know if a box is empty or not, so as to avert any overwriting in the first place. If the box is empty, this.taken = 0. If the box is filled by a player, taken = 1. If filled by AI, taken = 2. I made it matter whether it was AI or human so later i can check if one of them got tic tac toe. Anyway, by default the constructor class sets this.taken = 0. But the method for checking availability and writing the X or O uses a switch which checks if taken = 0. If it is, it sets taken to either 1 or 2 and writes the necessary symbol. If taken = 1 or 2, it just alerts the player that the spot is taken. But for some reason the switch statement can't tell when taken = anything other than 0. It always executes the code for 0 even though the code for 0 inherently makes it so that taken never equals 0 again, which means case 0 cannot happen anymore. Below is the code with notes. Code: function main(input){//start of main function// function Click(who, where, what){ //this is the method for checking if it's taken or not and writing the X or O if it isn't// /*the argument who represents a number. 0 is no one, 1 is human, 2 is AI; where is a string literal representing the spot on the grid*/ switch(this.taken){ case 0: this.taken = who; document.getElementById(where).innerHTML = what; break; case 1: alert("this spot is taken"); break; case 2: alert("this spot is taken"); }//end switch }//end Click function Box(inputhere){//start of class// this.taken = 0; this.pick = Click; } //end of Box class// //object declarations (I cut out most of them and left only the relevant ones// var topleft = new Box(); var topmid = new Box(); var topright = new Box(); var centerright = new Box(); //end of object declarations// switch (input){ /*in each .pick(), the first arg is whether or not a player chose it (1 = player did, 2 = comp did). The second arg is which box and the third is whether to put an X or O. The input variable in the switch statement is an argument passed through main() when the player clicks on a box. Topleft passes 1.1, topmid passes 1.2 and so on.*/ case 1.1:{ //The first instance of .pick() in each case is what the player did. The second is what the AI will do in repsonse.// topleft.pick(1, "topleft", "X"); topmid.pick(2, "topmid", "<span>O</span>"); break; }//end of case 1.1 case 1.3:{ topright.pick(1, "topright", "X"); centerright.pick(2, "centerright", "<span>O</span>"); break; }//end of case 1.3 }//end of switch }//end of main// Is there anyone who has any idea why on earth this is happening? I've been at it for an embarrassing amount of hours. Also, thanks to anyone who even considers helping : ) (feel free to flame me if my code sucks or my post is too long or anything). Hi Experts here, Pls help. I have written the html code like this: <a href="http://mypage.com/docfiles" target="_blank"> Click </a> But the problem is when ever the user click the click option complete url is displaying in two ways 1)on the buttom of the status bar 2)Right click on the option open the properties than also we are getting the complete url. But we don't want to see the complete url,How to hide the Url. Please give me solution I am struggling alot. Thanks and Regards, Srinivas yadav. Hello, I'm in need of some help. I have a form that I want to clone and add up to 5 duplicates with slight changes. The changes a Add a second question and another set of related radio buttons for only the duplicates. Change the title in the Header to increment by 1 ex. Header 1, Header 2... I also would like to make the form elements "id" and "names" unique. Also, continue to use the add and remove button at the bottom. I hope this is doable. Any help will be appreciated. I have included my existing code. NOTE: for a visual, I mocked up the the original form and 1 copy of the fields in the html, not to be used. Code: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <head> <title></title> <script type="text/javascript" src="http://tablesorter.com/jquery-latest.js"></script> </head> <body> <script type="text/javascript"> $(document).ready(function() { $('#btnAdd').click(function() { var num = $('.clonedInput').length; // how many "duplicatable" input fields we currently have var newNum = new Number(num + 1); // the numeric ID of the new input field being added var newElem = $('#section' + num).clone().attr('id', 'section' + newNum); newElem.children(':first').attr('id', 'first' + newNum).attr('name', 'first' + newNum).val(''); newElem.children(':first').attr('id', 'last' + newNum).attr('name', 'last' + newNum).val(''); newElem.children(':first').attr('id', 'phone' + newNum).attr('name', 'phone' + newNum).val(''); newElem.children(':first').attr('id', 'email' + newNum).attr('name', 'email' + newNum).val(''); newElem.children(':first').attr('id', 'yes' + newNum).attr('name', 'yes' + newNum).val(''); newElem.children(':first').attr('id', 'no' + newNum).attr('name', 'no' + newNum).val(''); $('#section' + num).after(newElem); $('#btnDel').attr('disabled',''); if (newNum == 5) $('#btnAdd').attr('disabled','disabled'); }); $('#btnDel').click(function() { var num = $('.clonedInput').length; // how many "duplicatable" input fields we currently have $('#section' + num).remove(); // remove the last element $('#btnAdd').attr('disabled',''); // enable the "add" button // if only one element remains, disable the "remove" button if (num-1 == 1) $('#btnDel').attr('disabled','disabled'); }); $('#btnDel').attr('disabled','disabled'); }); </script> <form id="myForm"> <div id="section1" style="margin-bottom:4px; border-bottom:1px solid #000; width: 400px;" class="clonedInput"> <br> <br> <div style=" font-weight:bold; border: 1px solid #000; padding:4px;background:#CCC; font-size:18px; margin-bottom:5px;">Header</div> First: <input type="text" name="first1" id="first1" /> <br> <br> Last: <input type="text" name="last1" id="last1" /> <br> <br> <br /> <div style=" font-weight:bold;padding:4px;">Header 2</div> <div>Show this question and radios on load of page.</div> <div> <input type="radio" id="yes1" class="eRad" name="yes1" value="" /> <label class="" for="yes">Yes</label> <input type="radio" id="no1" class="eRad" name="no1" value="" /> <label class="" for="no">No</label> </div> Phone: <input type="text" name="phone1" id="phone1" /> <br> <br> Email: <input type="text" name="email1" id="email1" /> </div> <div id="section1" style="margin-bottom:4px; border-bottom:1px solid #000; width: 400px;" class="clonedInput"> <br> <br> <div style=" font-weight:bold; border: 1px solid #000; padding:4px;background:#CCC; font-size:18px; margin-bottom:5px;">Header 2 (increment this number)</div> <div>Show this new question and radios on all copies</div> <div> <input type="radio" id="yes_a2" class="eRad" name="yes_a2" value="" /> <label class="" for="yes">Yes</label> <input type="radio" id="no_a2" class="eRad" name="no_a2" value="" /> <label class="" for="no">No</label> </div> First: <input type="text" name="first2" id="first2" /> <br> <br> Last: <input type="text" name="last2" id="last2" /> <br> <br> <br /> <div style=" font-weight:bold;padding:4px;">Sub Header 2 (increment this number)</div> <div>Show this question and radios on load of page.</div> <div> <input type="radio" id="yes_a2" class="eRad" name="yes_a2" value="" /> <label class="" for="yes">Yes</label> <input type="radio" id="no_a2" class="eRad" name="no_a2" value="" /> <label class="" for="no">No</label> </div> Phone: <input type="text" name="phone2" id="phone2" /> <br> <br> Email: <input type="text" name="email2" id="email2" /> </div> <div style="margin-top:10px;"> <input type="button" id="btnAdd" value="add another name" /> <input type="button" id="btnDel" value="remove name" /> </div> </form> </body> </html> -Cheers I HAVE BEEN TRYING TO FIGURE OUT THE PARAMETERS IN THE FUNCTIONS, INCLUDING THE ARRAYS [i], [p], ["get_" + i], ["set_" + i] AND HOW THE METHODS ARE BEING CALLED IN RELATION TO i, p and val, so that I can make sense of this code. If possible can you explain the code also What I will like to know are the properties and methods of the objects generated in the following code? Also I want to know how I can use those methods to show and change the name and age for the emp2 object. this is the code: function Employee(properties) { for (var i in properties) { if (properties.hasOwnProperty(i) && typeof properties[i] != 'function') { this["get_"+i] = (function(p) { return function() { return properties[p]; }; })(i); this["set_"+i] = (function(p) { return function(val) { properties[p] = val; }; })(i); } } } var emp1 = new Employee({ name: "Bob", age: 35, foo: function() {} }); var emp2 = new Employee({ name: "Gary", age: 54 }); I don't even know where to begin with this one. I don't know the terminology for what I am trying to do here, and the sample code is too big and cluttered to post. So I put together the following to illustrate the structure of the object that I am trying to overcome. I have a method chain within an object, and I need to override one of the methods, but when I do so I loose access to the private methods and properties of it's containing object... I googled this for several hours, and the best that I can come up with is that I need to somehow use call() to access the scope of another object. But I don't understand call() or apply() at all, and I've read many tutorials on those... Code: window.oModule['Report'] = (function(){ var _privateProp1 = '' , _privateMethod1 = function(){ // ... } , _publicMethod1 = function(){ // ... } , _publicMethod2 = (function(){ var _sub_privateProp1 = '' , _sub_privateMethod1 = function(param1,param2){ // ... } , _sub_publicMethod1 = function(){ // ... } , _sub_publicMethod2 = function(start , end){ // I need to replace this method from somewhere else var _neededValue = ''; for(var i = start ; i<end ; ++i) { // ... _neededValue += _sub_privateMethod1(arg1,arg2) } return _neededValue; } ; return{ '_sub_publicMethod1' : _sub_publicMethod1 , '_sub_publicMethod2' : _sub_publicMethod2 } })() ; return{ '_publicMethod1' : _publicMethod1 , '_publicMethod2' : _publicMethod2 } })(); alert(oModule.Report._publicMethod2._sub_publicMethod2(1,5)) // This works fine oModule.Report._publicMethod2._sub_publicMethod2 = function(start,end){ // Doing this modifies the output of all expressions that already call the sub method (which is what I need) var _neededValue = ''; // ... return start+end } alert(oModule.Report._publicMethod2._sub_publicMethod2(1,5)) // This will alert 6 (as intended) oModule.Report._publicMethod2._sub_publicMethod2 = function(start,end){ // Doing this modifies the output of all expressions that already call the sub method (which is what I need) var _neededValue = ''; for(var i = start ; i<end ; ++i) { // ... different set of instructions _neededValue += _sub_privateMethod1(arg1,arg2) // This line causes an error: _sub_privateMethod1 is undefined } return _neededValue } I am dynamically appending an img to the inner HTML of an element, to add in help in the form of a clickable icon next to select elements. When the img is added to an anchor the image of course becomes part of the link, and clicking the image invokes the anchor's action. The img has an onclick handler which triggers the dynamic help pop-up. My problem is that I can't seem to block the default anchor action, and thus the anchor is invoked also. The img onclick handler is called before the anchor event is processed (an alert popup will block the anchor's execution until the alert is dismissed), but returning false from it does not block the anchor's action. Any suggestions? I can move the img element to be a peer of the anchor element instead of a child, but I would like a programmatic fix instead of changing the way it interacts with the DOM if possible. Thanks. Hey all, I've built a website for my music and I'm fairly new to all this so bear with me. Essentially, I have two flash-based music players on my site. One is a simple single-track player that auto-plays some background music for the site. The functionality is limited to the user starting/stopping the music and adjusting the volume. The other is an advanced music player featuring a playlist of preselected tracks and allows the user to start/stop music, rewind, fast forward, adjust volume and select tracks in the playlist. This player does not start automatically. My question is this: when someone visits the site, the single-track background music player will start. Is there code that would allow the advanced music player, should it be turned on (i.e. someone selects a track and plays it), to override and actually stop the play of the single-track? TIA! Hi, every time I try and alert: [ { number:0, secondnumber:0 }, { number:2, secondnumber:1 }, { number:1, secondnumber:2 } ] it just shows [object object], [object object], [object object]. Why is this and what can I do to make the record be shown as it is above in an alert? Thanks. I can't get any info from Firebug except that one line, uncaught exception [object Object]. The code fully worked, then I needed to make it dynamically create Sortables from the scriptaculous library based on how many X were in a table in my database, which I've done, and I'm thinking it may be a simple slight parse error of some type, I'm not too good with Javascript, because now my script barely works. I've double checked the script's source code, the PHP variables are exactly what they should be. Code: print<<<HERE Sortable.create('sortlist$box', { tag: 'img', overlap:'horizontal',constraint:false, containment: $list, dropOnEmpty: true, onChange: function(item) { var list = Sortable.options(item).element; if(changeEffect) changeEffect.cancel(); changeEffect = new Effect.Highlight('changeNotification', {restoreColor:"transparent" }); }, onDrop: function(item) { var thing=Sortable.options(item).element.identify(); var anchors = document.getElementById(thing).childNodes.length-2; if(anchors > 20){ alert('This box had 20 creatures in it already, your last action has not been saved.'); window.location.reload(); } else{ new Ajax.Request("saveImageOrder.php", { method: "post", parameters: { data: Sortable.serialize("sortlist$box") } }); } } }); HERE; $box++; } ?> }); </script> if you solve this I'll send ya $10 via paypal First off... I am new to javascript, and am learning while trying to add some cool extra features to an existing project. An existing JSP is generating the HTML page and table. I have retro-fitted it so that it adds to each input field a 'trigger' to the onkeyup event. The purpose of this trigger is check for the the cursor keys being pressed (UP, DOWN, LEFT, RIGHT) and then if it is a logically valid move, shift to the next cell in that direction. Code: <td class="inputField" rowspan="1" colspan="1" nowrap="nowrap"> <input name="ColorNumber0" id="" maxlength="" size="20" onchange="saveFieldObj(this)" onkeyup="return doOnKeyUp(event, 18, 14, 'ColorNumber0')" type="text"> </td> Now, the function it calls, doOnKeyUp, for the most part is working fine... when the input field in the table cells are a textbox or textarea, my method can re-focus the fields appropriately. HOWEVER, I am having a huge headache when the input field is a combo box. Basically, the value of the combo box is changed with the cursor keys (which is default combo box behaviour (I think)), instead of moving to the next editable cell in that chosen direction. Problem #1: My question: Is there a way to intercept/override the various onKey events or similar for the combo boxes. For the combo boxes, I want to continue to move between table cells UNLESS a do something specific, like press the spacebar to entire an update/modification mode for the current cell. Everything I have done so far does not prevent the combo box events from triggering. Any ideas? Problem #2: Also, I tried a nasty hack to try and get it to work, by trying to switch the combo box's value back 1 spot (if it appeared to be needed) by changing the <combo box>.selected value. However, that change never appears to be taking hold, so it is staying at whatever the original selected value was. For this one, I am just curious as to the correct way to have javascript change the selected value in a combo box and make it "stick" and make it applied to the view/UI? Code example: Code: var selectedIdx = (curObj.selectedIndex - 0); if ( selectedIdx < curObj.length ) { var newIdx = (selectedIdx-0) - 1; curObj[selectedIdx].selected = "0"; curObj[newIdx].selected = "1"; curObj[newIdx].focus(); //curObj.selectedIndex = newIdx; } You can probably tell by the code that I had been trying various things to change the combo box's selection via javascript, but none has worked for me. Any help on either topic would be greatly appreciated! I'm writing a program that involves a network of interconnected nodes (or simply objects in my example below). It depends on being able to access properties of an object's linked objects (a bit oddly worded, sorry)... Problem is I'm not sure how to properly access those properties... see below please. <script> //This is an example of a problem im having in my own code... //I want to access the name of the object within the links array wintin the object... var objA = {name: "Object A", links: [objB, objC]}; var objB = {name: "Object B", links: [objC, objD, objE]}; var objC = {name: "Object C", links: [objB]}; var objD = {name: "Object D", links: [objE]}; var objE = {name: "Object E", links: [objD]}; //ex: I want to access the name of Object A's first link... console.log(objA.links[0].name); </script> I'm hoping to get "Object B"... But instead I get: TypeError: Result of expression 'objA.links[0]' [undefined] is not an object. Is there another way around this? Any thoughts are appreciated. Hello together! I generate html code with jsp. In that jsp there a several framesets and frames. And yes i know, frames are not really up to date but it's an old program and i have to deal with it now. Anyway, in the top frameset i have an onload attribute like onload="load()". In the function load i want to access the Element.prototype object. But unfortunately typeof Element gives me "undefined". So i looked a little deeper and found that window.toString() gives me "[object]" and not as expected "[object window]" so somehow my window doesn't know that its construcor is Window. window.construcor is "undefined" as well. And i don't have access to the Element object. I really don't know where the error could be. When the page is loaded and i access the same window over the console, then everything is right. But in my function a can't get access to the objects i need. I also don't know what part of the code could be useful to post here, but maybe someone had a similar problem before? i should say that this problem only occurs in IE8. In IE9 it works perfectly. Has anyone any idea?? Hi all, I'm stumped on finding a way in javascript to create an object factory whose instances are also object factories. In short I want something like that below, but no joy ... any clues? Code: function createClass () { return new createClass() function createClass() { return new createInstance () function createInstance () { //Default properties, values and methods which might later be extended } } } var createDoor = createClass(); var door1 = createDoor(); var door2 = createDoor(); var createChair = createClass(); var chair1 = createChair (); var chair2 = createChair (); Ignore post (if mod, please delete)
Hi, I've done control in asp.net/javascript and it works on some pages of mine and as it often happens doesn't work on customer's pages . All pages are run in IE 6.0. After I run debugger I've found out that on my page offsetLeft/Top clientHeight properties have some non-zero values. I have <span id="listCLient" style="width:200px;">..</span> and on my test page elListClient.clientHeight = 200, but on customer's app's page it is 0x0 ? Same with other offsetXXX properties etc. But elListClient.style.height bears correct value. I use those properties everywhere. I think it is some settings somewhere ? or CSS styles ? Can anyone help ? Thanks a lot Vladislav |