elm/core-js/Signal/Keyboard.js

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1.4 KiB
JavaScript

Elm.Keyboard = { Raw : function() {
var keysDown = Elm.Signal.constant(["Nil"]);
var charPressed = Elm.Signal.constant(["Nothing"]);
function remove(x,xs) {
if (xs[0] === "Nil") return xs;
if (xs[1] === x) return xs[2];
return ["Cons", xs[1], remove(x,xs[2])];
}
function has(x,xs) {
while (xs[0] !== "Nil") {
if (xs[1] === x) return true;
xs = xs[2];
}
return false;
}
Value.addListener(document, 'keydown', function(e) {
if (has(e.keyCode, keysDown.value)) return;
var hasListener = Dispatcher.notify(keysDown.id, ["Cons", e.keyCode, keysDown.value]);
if (!hasListener)
this.removeEventListener('keydown',arguments.callee,false);
});
Value.addListener(document, 'keyup', function(e) {
var codes = remove(e.keyCode, keysDown.value);
var hasListener = Dispatcher.notify(keysDown.id, codes);
if (!hasListener)
this.removeEventListener('keyup',arguments.callee,false);
});
Value.addListener(window, 'blur', function(e) {
var hasListener = Dispatcher.notify(keysDown.id, ["Nil"]);
if (!hasListener)
this.removeEventListener('blur',arguments.callee,false);
});
Value.addListener(document, 'keypress', function(e) {
var hasListener = Dispatcher.notify(charPressed.id, ["Just",e.charCode || e.keyCode]);
Dispatcher.notify(charPressed.id, ["Nothing"]);
if (!hasListener)
this.removeEventListener('keypress',arguments.callee,false);
});
return {keysDown:keysDown,
charPressed:charPressed};
}()
};