virt2/api/soft/CodeMirror/lib/util/event.js

104 lines
3.2 KiB
JavaScript
Executable File

import { mac } from "./browser.js"
import { indexOf } from "./misc.js"
// EVENT HANDLING
// Lightweight event framework. on/off also work on DOM nodes,
// registering native DOM handlers.
const noHandlers = []
export let on = function(emitter, type, f) {
if (emitter.addEventListener) {
emitter.addEventListener(type, f, false)
} else if (emitter.attachEvent) {
emitter.attachEvent("on" + type, f)
} else {
let map = emitter._handlers || (emitter._handlers = {})
map[type] = (map[type] || noHandlers).concat(f)
}
}
export function getHandlers(emitter, type) {
return emitter._handlers && emitter._handlers[type] || noHandlers
}
export function off(emitter, type, f) {
if (emitter.removeEventListener) {
emitter.removeEventListener(type, f, false)
} else if (emitter.detachEvent) {
emitter.detachEvent("on" + type, f)
} else {
let map = emitter._handlers, arr = map && map[type]
if (arr) {
let index = indexOf(arr, f)
if (index > -1)
map[type] = arr.slice(0, index).concat(arr.slice(index + 1))
}
}
}
export function signal(emitter, type /*, values...*/) {
let handlers = getHandlers(emitter, type)
if (!handlers.length) return
let args = Array.prototype.slice.call(arguments, 2)
for (let i = 0; i < handlers.length; ++i) handlers[i].apply(null, args)
}
// The DOM events that CodeMirror handles can be overridden by
// registering a (non-DOM) handler on the editor for the event name,
// and preventDefault-ing the event in that handler.
export function signalDOMEvent(cm, e, override) {
if (typeof e == "string")
e = {type: e, preventDefault: function() { this.defaultPrevented = true }}
signal(cm, override || e.type, cm, e)
return e_defaultPrevented(e) || e.codemirrorIgnore
}
export function signalCursorActivity(cm) {
let arr = cm._handlers && cm._handlers.cursorActivity
if (!arr) return
let set = cm.curOp.cursorActivityHandlers || (cm.curOp.cursorActivityHandlers = [])
for (let i = 0; i < arr.length; ++i) if (indexOf(set, arr[i]) == -1)
set.push(arr[i])
}
export function hasHandler(emitter, type) {
return getHandlers(emitter, type).length > 0
}
// Add on and off methods to a constructor's prototype, to make
// registering events on such objects more convenient.
export function eventMixin(ctor) {
ctor.prototype.on = function(type, f) {on(this, type, f)}
ctor.prototype.off = function(type, f) {off(this, type, f)}
}
// Due to the fact that we still support jurassic IE versions, some
// compatibility wrappers are needed.
export function e_preventDefault(e) {
if (e.preventDefault) e.preventDefault()
else e.returnValue = false
}
export function e_stopPropagation(e) {
if (e.stopPropagation) e.stopPropagation()
else e.cancelBubble = true
}
export function e_defaultPrevented(e) {
return e.defaultPrevented != null ? e.defaultPrevented : e.returnValue == false
}
export function e_stop(e) {e_preventDefault(e); e_stopPropagation(e)}
export function e_target(e) {return e.target || e.srcElement}
export function e_button(e) {
let b = e.which
if (b == null) {
if (e.button & 1) b = 1
else if (e.button & 2) b = 3
else if (e.button & 4) b = 2
}
if (mac && e.ctrlKey && b == 1) b = 3
return b
}