Sometimes JavaScript could be used to perform really stressful task and a loop, a for in, or an each, could not be fast enough to make your DOM responsive.
What we need in this case is simply a closure to make sure references are consistent and our job will end up in the correct order.
This is a probably silly but I hope interesting function to make the DOM and generally the page more responsive:
Time = {
setTimeout:function(Stack, delay){
var self = this;
if(!delay)
delay = 1;
if(!(Stack instanceof Array))
Stack = [Stack];
setTimeout(function(){
Stack.shift().call(self);
if(0 < Stack.length)
setTimeout(arguments.callee, delay);
}, delay);
}
};
We can call this functon in different ways, stating from the demo:
Time.setTimeout([
function(){
alert("Hello");
},
function(){
alert("Distributed");
},
function(){
alert("Work");
}
]);
untill its more meaningful usage:
var distributed = [];
$("whatever").each(function(i, dom){
distributed.push(function(){
// your stuff to do with i or dom element
});
});
distributed.push(function(){
// your stuff to do after the each call
});
Time.setTimeout(distributed);
Another trick? The usage of the scope injected by each function:
$("whatever").each(function(i, dom){
var self = this;
distributed.push(function(){
return function(){
// your stuff to do with i or dom element
}.call(self);
});
});
Closures against Responsiveness
People expect usability, we expect performances ... at the same time we would like to be able to show a progress, something, that indicate that the page is not completely blocked.
This is a simple way to solve the problem, portable enough, and customizable via closures ... I hope you'll enjoy it :)
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