I have an app-object constructer that looks like this:
var app = function(loadedsettings) {
return {
init: function() {
this.loop();
},
loop: function() {
this.update();
window.requestAnimationFrame(this.loop);
},
update: function() {
//loop through settings and call update on every object.
},
settings: [
//array of settings objects, all with update methods.
]
};
}
Then when I do:
var theApp = app(settings);
theApp.init();
I get:
Uncaught TypeError: Object [object global] has no method 'update'
because when requestAnimationFrame is called, the this-value inside the loop function is set to window.
Does anybody know how to call requestAnimatinFrame with the 'theApp' object set as the this-value?
I have an app-object constructer that looks like this:
var app = function(loadedsettings) {
return {
init: function() {
this.loop();
},
loop: function() {
this.update();
window.requestAnimationFrame(this.loop);
},
update: function() {
//loop through settings and call update on every object.
},
settings: [
//array of settings objects, all with update methods.
]
};
}
Then when I do:
var theApp = app(settings);
theApp.init();
I get:
Uncaught TypeError: Object [object global] has no method 'update'
because when requestAnimationFrame is called, the this-value inside the loop function is set to window.
Does anybody know how to call requestAnimatinFrame with the 'theApp' object set as the this-value?
Share Improve this question asked May 14, 2013 at 22:54 acrmuuiacrmuui 2,0701 gold badge23 silver badges33 bronze badges2 Answers
Reset to default 10You can create a bound function (with a fixed this
), and pass that to requestAnimationFrame:
var app = function(loadedsettings) {
return {
init: function() {
this.loop();
},
loop: function() {
this.update();
window.requestAnimationFrame(this.loop.bind(this));
},
update: function() {
//loop through settings and call update on every object.
},
settings: [
//array of settings objects, all with update methods.
]
};
}
I think that a browser which supports requestAnimationFrame will also support Function.prototype.bind, but in case you e across one that doesn't, there are polyfills available.
You need to cache a reference to this
:
var app = function(loadedsettings) {
var self = this;
return {
init: function() {
self.loop();
},
loop: function() {
self.update();
window.requestAnimationFrame(self.loop);
},
** snip **
...