JavaScript/Notes/CustomEvents

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Under Construction

An event is a function call that signifies something happened. Custom events are functions that you call to notify subscribers. The function is either defined by the "class" (default) or shadowed on the instance, by the client of the API.

<source lang="javascript"> var TableSort = new Factory(function() {


 function _getSortFunction(sortType) {
   if(sortType == "number") {
    return function() { }
   }
 }
 function _isSortedBy(tableSort, sortType) {
   
 }
 var configData = {};
 function TableSort(id, config) {
   this.id = id;
   configData[id] = Object.create(config);
 }
 TableSort.prototype.sortBy = function(sortType) {
   var config = configData[this.id];
   if(!config.currentSort != "sortType") {
     config.sortFunction(this);
     this.onsort(sortType);
   }
 };
 return TableSort;

}); </source> The Factory is explained in Factory lesson.

Use a shared a noop function for the onsort event. Function.prototype is itself a function that does nothing and returns undefined. <source lang="javascript"> TableSort.prototype = {

 sortBy : function(sortType) {
   var config = configData[this.id];
   if(!config.currentSort != sortType) {
     config.sortFunction(this);
     this.onsort(sortType);
   }
 },

 onsort : Function.prototype

}; </source>

Instantiate and Listen for onsort

Instantiate the object and add an event handler to the instance. <source lang="javascript"> var propertiesTable = TableSort.getById("properties", { "price" : function(row} { } }); propertiesTable.onsort = function(sortType) {

 updateHeader(sortType);

}; </source>