dojo.disconnect¶
| since: | 0.9 |
|---|
Contents
Disconnects methods from linked events.
Introduction¶
Dojo’s event system provides dojo.disconnect to cleanly remove event listeners created by dojo.connect. The more events in the page that exist, the more the browser (or otherwise) has to do.
Usage¶
disconnect() accepts a specially-crafted parameter as it’s only argument which, coincidentally, is the return value from dojo.connect.
For example, to setup a function to run when a node is clicked, then remove it after the first time it is clicked:
[ Dojo 1.7 AMD ]
require(["dojo/dom", "dojo/_base/connect"], function(){
var node = dom.byId("someButton");
var handle = connect.connect(node, "onclick", function(e){
alert("you won't see me again!");
connect.disconnect(handle);
});
});
[ Dojo < 1.7 ]
var node = dojo.byId("someButton");
var handle = dojo.connect(node, "onclick", function(e){
alert("you won't see me again!");
dojo.disconnect(handle);
});
This works with any connection dojo.connect is able to make: DOM Connections, Dijit events, etc.
A very common pattern is to store a series of return values in an array, and use dojo.forEach to iterate over them, disconnecting several connections at once:
[ Dojo 1.7 AMD ]
require(["dojo/_base/connect", "dojo/_base/array"], function(connect, array){
var connections = [];
connections.push(
connect.connect(node, "onmouseenter", function(){ /* smart mouseover code */ })
)
connection.push(
connect.connect(node, "onmouseleave", function(){ /* smart mouseout code */ })
)
connect.connect(node, "onclick", function(){
// disable the other mouse events:
array.forEach(connections, connect.disconnect);
});
});
[ Dojo < 1.7 ]
var connections = [];
connections.push(
dojo.connect(node, "onmouseenter", function(){ /* smart mouseover code */ })
)
connection.push(
dojo.connect(node, "onmouseleave", function(){ /* smart mouseout code */ })
)
dojo.connect(node, "onclick", function(){
// disable the other mouse events:
dojo.forEach(connections, dojo.disconnect);
});
This works because forEach passes each of the Array items as the first parameter to the passed function (in this case, dojo.disconnect), thus removing each of the stored connections when that node is clicked.