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Using jQuery UI

cconstan

Better understanding call back functions

in Using jQuery UI • 5 months ago

The autocomplete UI plugin has a source option to specify the suggestions to be givveb to the user. The third variation of this option is a callback function.This callback gets two arguments:


 a request

object, with a single term property, which refers to the value currently in the text input and a



 a response

callback, which expects a single argument: the data to suggest to the user

How this works behind the hood?

How/When is the Object created?
How/When is the response callback called?

1

Replies(1)

Kevin B

Re: Better understanding call back functions

5 months ago

It is probably implemented something like this:

var timer;
var options = {
delay: 150,
source: null
};
$(element).keydown(function(){
clearTimeout(timer);
timer = setTimeout(function(){
if ( $.isFunction(options.source) ) {
options.source.call(element, { term: element.value }, function(data){
displaySuggestions(data);
});
}
else {
displaySuggestions( $.grep(options.source,function(){
return this.indexOf(element.value) >= 0;
}));
}
},options.delay);
});

The jQuery UI plugin is of course using the widget factory, the above i just typed up.

-- Kevin