java - Delay code execution within a function in Javascript / Java

Question

I have an onclick javascript function (invoked from DOJO components through .jsp file) within which two UI components are loaded at the same time in js file (through an AJAX call to the Spring Controller (java file) and back to the JSP/Javascript file.)

The problem is that the second component loads before the first component and is not displaying the prescribed data . I would like to know how to set a delay before calling the code in javascript to delay the second component in milliseconds.

Note :

1. I used Thread.sleep(msecs) in my controller which seems to work fine and resolves my issue. But I dont want to use that knowing the risk it poses. So request an alternative instead of this.

2. Also I used setTimeOut() function but setTimeOut() requires a function as an argument. I need to just delay the code within the function for a few milliseconds the first time only. From second time onwards I dont want to delay the code being called.

Request ur valuable inputs.

Answer 1

Delaying the execution of code is not a good idea. In development, the calls might be executed and returned in the order you want. But in a production environment with a system under load, the timing of the server calls being executed may not be consistent.

I am assuming that you are using dojo/xhr to make the ajax calls and your solution is to use a DeferredList.

http://dojotoolkit.org/reference-guide/1.9/dojo/DeferredList.html

var d1 = xhr(...);
    d2 = xhr(...);

var dl = new DeferredList([d1, d2]);

dl.then(function(result){
    // Execute the code that requires both calls to be completed.
});

Answer 2

也许您的问题可以通过使用http://dojotoolkit.org/reference-guide/1.8/dojo/domReady.html?highlight=domready来解决，以确保 dom 已完全加载

或使用 dojo/defered

http://dojotoolkit.org/reference-guide/1.8/dojo/Deferred.html?highlight=domready

问候

Answer 3

JavaScript 不允许阻塞线程，因此您可以使用的唯一选项是 setTimeOut() 函数。或者，您可以在第一个组件在加载时通​​知第二个组件并且此时第二个组件重新加载自身时实现机制。