So how I can control the page contents loading sequence in dojo

Question

Hi there,

I'm using dojo for our UI's, and would like to load certain part of page contents in sequence. For example, for a certain stock, I'd like to load stock general information, such as ticker, company name, key stats, etc. and a grid with the last 30 days open/close prices. Different contents will be fetched from the server separately. Now, I'd like first load the grid so the user can have something to look at, then, say, start loading of key stats which is a large data set takes longer time to load. How do I do this. I tried: dojo.addOnLoad(function() {

startGrid(); //mock grid startup function which works fine getKeyStats(); //mock key stat getter function also works fine });

But dojo is loading getKeyStats(), then startGrid() here for some reason, and sequence doesn't seem be matter here. So how I can control the loading sequence at will? Thanks in advance!

David

Answer 1

The sequence doesn't matter because they are asynchronous requests; they appear in the same order as responses were received from the server, which is not necessarily the same order as they were called in.

To load them in the correct order, make your requests as normal. Add a callback for a successful response that places the response data into a shared bucket in any order. Once you have the proper number of responses (check it at the end of your callback), start inserting data into the page in any order you like.

Answer 2

you may want to look at dojo.publish and use a pub sub pattern to loosely couple these events so that you can order them. Pub sub will allow you to make the request and listen for all topics to fire. With this you could call the request asynchronously and load the widgets in there respective place while styling them hidden and use the pub sub to make them visible based on a sequence of topic publications.