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Creating .json file and storing data in javascript -- using vis.js

In my project I need to save the data to .txt or .xml or .json file. I could not find any answer from vis.js website/issues blog. It might be simple, do not know. Really helpful if anyone help me out with example code. Thank you so much in advance.
function saveData(data,callback) {
data.id = document.getElementById('node-id').value;
data.label = document.getElementById('node-label').value;
clearPopUp();
callback(data);
}

If I understand you correctly, you are looking for a way to save data and options of a graph. In my graph editor adaptation for TiddlyWiki Classic I use the following method to extract data (the full implementation can be found in the repo, see config.macros.graph.saveDataAndOptions, here's a simplified one):
config.macros.graph.saveDataAndOptions = function(network,newOptions) {
newOptions = newOptions || {};
// get nodes and edges
var nodes = network.body.data.nodes._data; // contains id, label, x,y, custom per-node options and doesn't contain options from options.nodes; presumably contains option values set when network was created, not current ones (it is so for x,y)
// no suitable getter unfortunately
var edges = network.body.data.edges._data; // map; for edges to/from? certain node use network.getConnectedNodes(id)
// network.body.data.edges._data is a hash of { id: , from: , to: }
// get node positions, options
var positions = network.getPositions(), // map
options = // get options stored previously
// merge newOptions into options
for(var nodeId in nodes) {
// nodes[nodeId].x is the initial value, positions[nodeId].x is the current one
if(positions[nodeId]) { // undefined for hidden
nodes[nodeId].x = positions[nodeId].x;
nodes[nodeId].y = positions[nodeId].y;
}
storedNode = copyObjectProperties(nodes[nodeId]);
storedNodes.push(storedNode);
}
//# do whatever you need with storedNodes, edges and options
// (pack them with JSON.stringify, store to a file etc)
};
However, while this works ok for storing data, this only helps to save options passed for storing explicitly which can be not very nice for some cases. I use this method in manipulation helpers and on dragEnd (network.on("dragEnd",this.saveToTiddlerAfterDragging), config.macros.graph.saveToTiddlerAfterDragging = function(stuff) { config.macros.graph.saveDataAndOptions(this,{ physics: false }); };). I haven't recieved any better suggestions, though.
If you need to get data and options reactively and setting such helper to handle certain edit events can't solve your problem, then I suggest wrapping nodes, edges and options as vis.DataSet and save those when needed. This is related too.
To answer the question about events/other ways to use such methods. Here's how I use them:
I save data after drag&drop moving of nodes, this is done using an event handler. Namely, I introduced
config.macros.graph.saveToTiddlerAfterDragging = function(stuff) {
config.macros.graph.saveDataAndOptions(this,{ physics: false });
};
(when drag&drop is used, physics should be switched off, otherwise coordinates won't be preserved anyway) and then I use
network.on("dragEnd",this.saveToTiddlerAfterDragging);
so that changes are saved.
As for saving after adding/editing a node/edge, I apply saving not by an event (although it's nice thinking, and you should try events of DataSet, since there's no special graph events for that). What I do is I add an elaborated hijack to the manipulation methods. Take a look at the source I've linked after the
var mSettings = options.manipulation;
line: for each manipulation method, like options.manipulation.addNode I hijack it so that its callback is hijacked to call config.macros.graph.saveDataAndOptions in the end. Here's a simplified version of what I'm doing:
var nonSaving_addNode = options.manipulation.addNode;
options.manipulation.addNode = function(data,callback) {
// hijack callback to add saving
arguments[1] = function() {
callback.apply(this,arguments); // preserve initial action
config.macros.graph.saveDataAndOptions(network); // add saving
};
nonSaving_addNode.apply(this,arguments);
}
The thing is, addNode is actually called when the add node button is clicked; though, I'm using a customized one to create a popup and apply changes once user is happy with the label they chose.

Can't access children of Konva Stage after cloning

I have a problem with konvajs. I have a konva Stage that I clone into a temporary Stage, so I can revert changes made by a user, when the user cancels.
The way I do this is, that I clone the existing Stage into a temporary one, destroy the children of the origin and after that I move the children of the temporary Stage back to the original and destroy the temporary Stage. The problem is, when I try to access the children now, for example via findOne('#id-of-child'), I get undefined, even though the children exist.
Here's what I've done so far:
clone: function()
{
var cloned_stage = this.stage.clone();
Array.each(this.stage.getChildren(), function(layer, lidx) {
if (layer.attrs.id) {
// setting the id to the ones, the children had before
cloned_stage.children[lidx].attrs.id = layer.attrs.id;
}
});
return cloned_stage;
},
restore: function(tmp_stage)
{
this.stage.destroyChildren();
Array.each(tmp_stage.getChildren(), function(layer, lidx) {
var tmp_layer = layer.clone();
tmp_layer.attrs.id = layer.attrs.id;
tmp_layer.moveTo(this.stage);
}.bind(this));
tmp_stage.destroy();
this.stage.draw();
},
Now when the user opens the toolbox to change something, the current stage is cloned with the "clone" function and when the user cancels his changes, the "restore" function is called with the cloned stage as parameter.
But after that when I try to do things like the following they do not work as expected.
some_child_of_the_stage.getLayer(); -> returns null
var edit_layer = this.stage.findOne('#edit-layer'); -> returns undefined
But the "some_child_of_the_stage" does exist and has a layer of course and the stage has a child with the id "edit-layer".
Me and my colleague are at our wit's end.
I appreciate any help and suggestions thank you.
Update:
A short fiddle showing the problem via console.log:
fiddle

It is better not to touch attrs property of a node and use public getters and setters.
Konva has special logic for storing id property. Selector by id #edit-layer may not work because of direct access to attrs id.
You can use name property fo that case.
https://jsfiddle.net/s36hepvg/12/

reuse serialized reference to "this"-Keyword

First things first: I'm not sure whether the information that I'm going to provide will be enough, I will happily add additional information if needed.
I'm serializing a complex structure into the JSON-Format, Field[i][0] is the "this"-reference to an object.
Firebug's Output on JSON.Stringify(myObj)
This is all fine and working as long as I keep it all JS. But now I have the requirement to serialize and send it to my backend to get the reference + computed information back.
Now how do I map back to the reference I had before? How do I bind this ref back to an Object?
This $$hash thing looks internal and proprietarish so I havent even bothered trying something like Object[$$hash] = ref or whatever.
This general idea probably seems pretty whack, but the result is returned asynchrously and I need an identifier to bind the new information back to the original object. Obviously I could just make up my own identifier for that, but I was wondering whether there's an option to solve it this way.
EDIT
The objects are created like this (likewise)
var arrayOfObj = []
arrayOfObj.push(new Object.With.SomeSettersAndGetters());
The Object has a method like
function GetRef(){
return this;
}
Which I'm using to keep a ID/Ref through my code.
Thank you!

Update
If you want to update a series of instances and make many Ajax requests, then you need to look at Ajax long polling and queueing techniques. You won't be able to preserve the reference, but regardless of what Ajax technique you use, make use of the below trick to preserve the reference.
Add long polling on top and you're good to go.
The idea is this:
Assume the server will respond in JSON format. If you need to refer to the original references, here's my two cents:
Update the exact references when the server replies. Say you have 10 instances of Something stored in an array. On a successful response, you use the methods in the Something class to update the specific instances in whatever way you want.
/**
* The array with something instances.
* #type {Array.<Something>}
*/
var instances = [];
/**
* The Ajax success function.
* #param {Event} event The event object.
*/
function ajaxSuccess(event) {
var response = event.target.getResponseText();
var actualResponse = JSON.parse(response);
for (var i = 0, len = actualResponse.length; i++) {
instances[i].setWhatever(actualResponse[i].whatever);
};
};
The above is a more procedural approach. If you want full blown OOP in JS, then you think in modular design patterns. Say you have a module that loads data into some place. Basically, everything related to that module is an instance property.
var myModule = function() {
this.whatever = 1;
};
myModule.prototype.loadMore = function() {
var request = new XMLHttpRequest(),
that = this; // store a reference to this.
request.send(); // etc
request.onreadystatechange = that.onSucess;
};
myModule.prototype.onSucess = function(event) {
var response = JSON.parse(event.target.getResponseText());
this.whatever = response.whatever;
};
var moduleInstance = new myModule();
myModule.loadMore();
// Now the scope is always preserved. The callback function will be executed in the right scope.
Let's assume on the backend side of things, you have a model class that mimics your client side JavaScript model. Say you want to update a reference inside a model that displays text. I use Scala on the backend, but look at the fields/properties and ignore the syntax.
case class Article (
title: String,// these are my DB fields for an Article.
punchline: String,
content: String,
author: String
);
// now assume the client is making a request and the server returns the JSON
// for an article. So the reply would be something like:
{"title": "Sample title", "punchline": "whatever", "content": "bla bla bla boring", "author": "Charlie Sheen"};
// when you do
var response = JSON.parse(event.target.getResponseText());
// response will become a JavaScript object with the exact same properties.
// again, my backend choice is irrelevant.
// Now assume I am inside the success function, which gets called in the same scope
// as the original object, so it refers TO THE SAME THING.
// the trick is to maintain the reference with var that = this.
// otherwise the onSuccess function will be called in global scope.
// now because it's pointing to the same object.
// I can update whatever I want.
this.title = response.title;
this.punchline = response.punchline;
this.content = response.content;
this.author = response.author;
// or I can put it all in a single variable.
this.data = response;
What you need to remember is that scope needs to be preserved. That's the trick.
When I do var that = this; I copy a reference to the model instance. The reference is remembered through higher-order, not current scope.
Then I tell the XMLHttpRequest object to call that.ajaxSuccess when it is complete. Because I used that, the ajaxSuccess function will be called in the scope of the current object. So inside the ajaxSuccess function, this will point to the original this, the same instance.
JavaScript remembers it for me it when I write var that = this;

jquery Syncing dom element values

I have a DOM element like this:
<div id='master-value'>Apples</div>
I have many other elements elsewhere on the page that I need to sync with the 'master-value'.
<div class='fruit-value' data-reference='master-value'>Apples</div>
<div class='some-fruit' data-reference='master-value'>Apples</div>
When I change the value of the 'master-value', I want all the synced elements to update with it.
$('#master-value').text('Pears');
Should affect:
<div class='fruit-value' data-reference='master-value'>Pears</div>
<div class='some-fruit' data-reference='master-value'>Pears</div>
What I don't want, is on every change of 'master-value' to have to search through all the elements in order to find the synced elements in order to change them. I think that's quite slow when there are many elements that needs to be searched through.
There should be some way for the child values to be pre-bound to the master value so that the selection goes quickly.
$('.fruit-value, .some-fruit').sync('#master-value');
I have some ideas, for instance: I can create an array of preselected synced objects, bind a custom event on the master value and run that event whenever I change the value. The event would go through the array to update all the child elements.
I'm sure there's a better way of doing it though...
Thanks!

You can store the selector once, like this:
var elements = $('.fruit-value, .some-fruit'); //do this once
elements.text($("#master-value").text()); //when you want to sync
The elements variable/jQuery object will keep an array of references to DOM elements so it won't be traversing to find them each time.

wouldn't it be easier to give them all the same class?
So you coud do
$('.fruit').text('Pears')

If you're looking for plugin type of functionality, try this:
When setting up, it takes an object with one property syncWith to set up the elements it should sync with.
When setting the text, it will set the text for the master and the synced elements.
Try it out: http://jsfiddle.net/GH33J/
Just a first attempt. There would be room for improvement if (for example) the master was more than one element. There should be a global reference to all the elements to synchronize and an option to tell if the masters should be synced too.
$.fn.sync = function(arg) {
// if arg plain object, we are doing an initial setup
if ($.isPlainObject(arg)) {
return this.each(function() {
$.data(this, 'syncWith', $(arg.syncWith));
});
// if arg is jQuery object, we are adding new items
} else if (arg.jquery) {
return this.each(function() {
var $set = $.data(this, 'syncWith');
$.each(arg, function() {
$set.push(this);
});
});
console.log(this.data('syncWith'));
// otherwise assume we have a string, and are syncing a new value
} else {
return this.each(function() {
$(this).text(arg);
$.data(this, 'syncWith').text(arg);
});
}
};
// Set up the sync
$('#master-value').sync({
syncWith: '.fruit-value,.some-fruit'
});
var $new = $('<div class="fruit-value">Apples</div>').appendTo('body');
// Pass a jQuery object containing newly created element(s) to add to the set
$('#master-value').sync($new);
// Activate a sync
$('#master-value').sync("pears");​

OK here we go:
This is the official data linking plugin from Microsoft. It's now being supported by the jQuery Core team, so we know it's good. :)
http://weblogs.asp.net/scottgu/archive/2010/05/07/jquery-templates-and-data-linking-and-microsoft-contributing-to-jquery.aspx
http://blog.jquery.com/2010/10/04/new-official-jquery-plugins-provide-templating-data-linking-and-globalization/

Advice needed... Javascript OOP/namespacing

right now i am at a point where i feel that i need to improve my javascript skills because i already see that what i want to realize will get quite complex. I've iterrated over the same fragment of code now 4 times and i am still not sure if it's the best way.
The task:
A user of a webpage can add different forms to a webpage which i call modules. Each form provides different user inputs and needs to be handled differently. Forms/Modules of the same type can be added to the list of forms as the user likes.
My current solution:
To make the code more readable and seperate functions i use namespaced objects. The first object holds general tasks and refers to the individual forms via a map which holds several arrays where each contains the id of a form and the reference to the object which holds all the functions which need to be performed especially for that kind of form.
The structure looks more or less similar to this:
var module_handler = {
_map : [], /* Map {reference_to_obj, id} */
init: function(){
var module = example_module; /* Predefined for this example */
this.create(module);
},
create: function(module) {
//Store reference to obj id in map
this._map.push([module,id = this.createID()]);
module.create(id);
},
createID: function(id) {
//Recursive function to find an available id
},
remove: function(id) {
//Remove from map
var idx = this._map.indexOf(id);
if(idx!=-1) this._map.splice(idx, 1);
//Remove from DOM
$('#'+id+'').remove();
}
}
var example_module = {
create: function(id) {
//Insert html
$('#'+id+' > .module_edit_inner').replaceWith("<some html>");
}
}
Now comes my question ;-)
Is the idea with the map needed?
I mean: Isn't there something more elegant like:
var moduleXYZ = new example_module(id)
which copies the object and refers only to that form.... Something more logical and making speed improvements?? The main issue is that right now i need to traverse the DOM each time if i call for example "example_module.create() or later on any other function. With this structure i cant refer to the form like with something like "this"???
Do you see any improvements at this point??? This would help me very much!!! Really i am just scared to go the wrong way now looking at all the stuff i will put on top of this ;-)
Thank You!

I think you're looking for prototype:
=========
function exampleModule(id)
{
this.id = id;
}
exampleModule.prototype.create = function()
{
}
=========
var module1 = new exampleModule(123);
module1.create();
var module2 = new exampleModule(456);
module2.create();