Deleting Connections when elements are deleted in jsPlumb

Removing the connections along with the parent element can be  little tricky if not correctly handled. This requires the maintenance of information regarding a connections source and target. 

In order to do so, we'll be using an array called 'list'. The list array is a two- dimensional array instantiated with the number of connections at the time of deletion of a parent element. 

An event listener will be called when the user clicks on the cancel icon of an element, as shown below. (I've tried as far as possible to simplify each and every code line via comments)



































The reason to declare the list array within the call to delete listener is the fact that there is no viable place other than this that could assure that the user has fully completed connecting as desired, plus there is little to no concern regarding this details up till an element needs to be deleted( up till what we've covered in this context, but the connection details are crucial when it comes to processing complex details as this develops)

Also, in the above code, I've used splice twice. One, within the fro loop and the other, after removing the element. This may seem redundant at first but I was forced to follow this accidentally as I kept on getting recurring undefined cells in my array. Well, let me explain this further. 

In the first for loop, we are splicing each individual cell. Hence, this is going to leave the list with columns where a source may existing but the target maybe undefined or vise versa. This kind of columns are worthless. So we check for such columns in the second splicing and we splice the entire column so that only useful data( ones that hold both the source and he target as a column) exists in the list array.


Comments

Post a Comment

Popular posts from this blog

Creating connections between Elements in jsPlumb

In my previous posts we've gone through creating a toolbox and canvas from which elements can be dragged from and dropped onto. Then we took a look at eliminating the replication of elements whenever a dropped clone was dragged within the canvas. So now let's move onto creating basic connections between these dropped elements using jsPlumb and jQuery-UI. Starting off with the code previously dealt with, creating connections requires only the addition of a few lines of code to your JS code. The droppable function part of the code has been shown below. Step 1: Assign a unique ID for each element being dropped on the canvas. Though jsPlumb will automatically assign an ID when you don't supply one, it is easier to manipulate the elements when you define an ID. This ID can be a simple digit or even a complex string( But remember, jsPlumb treats all IDs as strings). //Set a unique ID for each dropped Element var indexer = 0 ; function setId (element){ indexer ++; ...
Read more

AngularJS vs ReactJS

Image
Today I just came across an interesting question and thought of creating this. At many occasions, developers try to render ReactJS as the best over AngularJS. But, according to my personal opinion, this is purely opinionated and also strongly depends on the type of the project in context. First of all, here's a very brief definition of what AngularJS & ReactJS according to their documentations. AngularJS AngularJS is a structural framework for dynamic web apps. It lets you use HTML as your template language and lets you extend HTML's syntax to express your application's components clearly and succinctly. Angular's data binding and dependency injection eliminate much of the code you would otherwise have to write." Here's a perfect example to try out this. ReactJS   React.js is a JavaScript library for building user interfaces. (Famously used by Facebook) The comparison between the two has been jotted out in the following table...
Read more

interact.js Javascript Library

Image
Previously we've discussed enabling the drag and drop functionalities using the jsPlumb library. Recently, I stumbled upon the interact.js Javascript library, which I found to be as user-friendly as jsPlumb. Below is a short comparison of the two.    Library License Language/Infrastructure Level Built-in editor Github jsPlumb MIT/GPL2 HTML, JavaScript Medium Not Present 2931 stars, 755 forks interact.js MIT Standalone JavaScript Medium Not Present 5452 stars, 351 forks The above details are not presented here to render either one as the bet over the other.  But, in my own experience, I've blended both in my projects utilizing the drag and drop functions for some elements from jsPLumb and the drag and resize function for one element from inter.js. But the only concern when using both the libraries within one function, issues related to the drag function o...
Read more