git.iko.soy/elk
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elk/libraries/Native/Signal/Window.js
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2Elm.Native.Window = function(elm) {
3 'use strict';
5 elm.Native = elm.Native || {};
6 if (elm.Native.Window) return elm.Native.Window;
8 var Signal = Elm.Signal(elm);
9 var Tuple2 = Elm.Native.Utils(elm).Tuple2;
11 function getWidth() { return elm.node.clientWidth; }
12 function getHeight() {
13 return document.body === elm.node ? window.innerHeight : elm.node.clientHeight;
14 }
16 var dimensions = Signal.constant(Tuple2(getWidth(), getHeight()));
17 dimensions.defaultNumberOfKids = 2;
19 // Do not move width and height into Elm. By setting the default number of kids,
20 // the resize listener can be detached.
21 var width = A2(Signal.lift, function(p){return p._0}, dimensions);
22 width.defaultNumberOfKids = 0;
24 var height = A2(Signal.lift, function(p){return p._1}, dimensions);
25 height.defaultNumberOfKids = 0;
27 function resize(e) {
28 var w = getWidth();
29 var h = getHeight();
30 if (dimensions.value._0 === w && dimensions.value._1 === h) return;
31 var hasListener = elm.notify(dimensions.id, Tuple2(w,h));
32 if (!hasListener) window.removeEventListener('resize', resize);
33 }
34 window.addEventListener('resize', resize);
36 return elm.Native.Window = {
37 dimensions:dimensions,
38 width:width,
39 height:height
40 };
42};