主要知識(shí)點(diǎn)：
- 通過(guò)
on,one注冊(cè)自定義事件，并且只能通過(guò)trigger來(lái)觸發(fā) - 計(jì)算滾動(dòng)條的寬度，通過(guò)生成一個(gè)div節(jié)點(diǎn)，overflow為scroll，那么就有滾動(dòng)條了，然后就可以計(jì)算出滾動(dòng)條的寬度
- 把變量綁定在該dom元素的data的某個(gè)屬性上，這個(gè)很妙
/* ========================================================================
* Bootstrap: modal.js v3.3.7
* http://getbootstrap.com/javascript/#modals
* ========================================================================
* Copyright 2011-2016 Twitter, Inc.
* Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)
* ======================================================================== */
+function ($) {
'use strict';
// MODAL CLASS DEFINITION
// ======================
var Modal = function (element, options) {
this.options = options
this.$body = $(document.body)
this.$element = $(element)
this.$dialog = this.$element.find('.modal-dialog')
this.$backdrop = null
this.isShown = null
this.originalBodyPad = null
this.scrollbarWidth = 0
this.ignoreBackdropClick = false
if (this.options.remote) {
this.$element
.find('.modal-content')
.load(this.options.remote, $.proxy(function () {
this.$element.trigger('loaded.bs.modal')
}, this))
}
}
Modal.VERSION = '3.3.7'
Modal.TRANSITION_DURATION = 300
Modal.BACKDROP_TRANSITION_DURATION = 150
Modal.DEFAULTS = {
backdrop: true,
keyboard: true,
show: true
}
Modal.prototype.toggle = function (_relatedTarget) {
return this.isShown ? this.hide() : this.show(_relatedTarget)
}
// 第一個(gè)被調(diào)用的函數(shù)
Modal.prototype.show = function (_relatedTarget) {
// _relatedTarget是觸發(fā)的按鈕或a
// this指向modal實(shí)例
var that = this
// relatedTarget是jq event的屬性,返回當(dāng)前事件涉及到的其他dom元素,它的值是一個(gè)dom節(jié)點(diǎn)
var e = $.Event('show.bs.modal', { relatedTarget: _relatedTarget })
// 執(zhí)行了e事件
this.$element.trigger(e)
// 如果isShown為true那么下面的不執(zhí)行,最初的isShow為null，因此那后isShown為false,所以就是如果沒(méi)有modal顯示，那么執(zhí)行下面的代碼
if (this.isShown || e.isDefaultPrevented()) return
this.isShown = true
//檢查瀏覽器滾動(dòng)條的寬度
this.checkScrollbar()
// 如果溢出，給body的padding-right加上滾動(dòng)條的寬度
this.setScrollbar()
// 'modal-open'的效果是overflow：hidden
this.$body.addClass('modal-open')
this.escape()
this.resize()
// 自定義事件click.dismiss.bs.modal
this.$element.on('click.dismiss.bs.modal', '[data-dismiss="modal"]', $.proxy(this.hide, this))
this.$dialog.on('mousedown.dismiss.bs.modal', function () {
that.$element.one('mouseup.dismiss.bs.modal', function (e) {
if ($(e.target).is(that.$element)) that.ignoreBackdropClick = true
})
})
this.backdrop(function () {
var transition = $.support.transition && that.$element.hasClass('fade')
if (!that.$element.parent().length) {
that.$element.appendTo(that.$body) // don't move modals dom position
}
that.$element
.show()
.scrollTop(0)
that.adjustDialog()
if (transition) {
that.$element[0].offsetWidth // force reflow
}
that.$element.addClass('in')
that.enforceFocus()
var e = $.Event('shown.bs.modal', { relatedTarget: _relatedTarget })
transition ?
that.$dialog // wait for modal to slide in
.one('bsTransitionEnd', function () {
that.$element.trigger('focus').trigger(e)
})
.emulateTransitionEnd(Modal.TRANSITION_DURATION) :
that.$element.trigger('focus').trigger(e)
})
}
Modal.prototype.hide = function (e) {
if (e) e.preventDefault()
e = $.Event('hide.bs.modal')
this.$element.trigger(e)
if (!this.isShown || e.isDefaultPrevented()) return
this.isShown = false
this.escape()
this.resize()
$(document).off('focusin.bs.modal')
this.$element
.removeClass('in')
.off('click.dismiss.bs.modal')
.off('mouseup.dismiss.bs.modal')
this.$dialog.off('mousedown.dismiss.bs.modal')
$.support.transition && this.$element.hasClass('fade') ?
this.$element
.one('bsTransitionEnd', $.proxy(this.hideModal, this))
.emulateTransitionEnd(Modal.TRANSITION_DURATION) :
this.hideModal()
}
Modal.prototype.enforceFocus = function () {
$(document)
.off('focusin.bs.modal') // guard against infinite focus loop
.on('focusin.bs.modal', $.proxy(function (e) {
if (document !== e.target &&
this.$element[0] !== e.target &&
!this.$element.has(e.target).length) {
this.$element.trigger('focus')
}
}, this))
}
Modal.prototype.escape = function () {
console.log('this.isShown', this.isShown)
console.log('this.options.keyboard', this.options.keyboard)
if (this.isShown && this.options.keyboard) {
this.$element.on('keydown.dismiss.bs.modal', $.proxy(function (e) {
e.which == 27 && this.hide()
}, this))
} else if (!this.isShown) {
this.$element.off('keydown.dismiss.bs.modal')
}
}
Modal.prototype.resize = function () {
if (this.isShown) {
$(window).on('resize.bs.modal', $.proxy(this.handleUpdate, this))
} else {
$(window).off('resize.bs.modal')
}
}
Modal.prototype.hideModal = function () {
var that = this
this.$element.hide()
this.backdrop(function () {
that.$body.removeClass('modal-open')
that.resetAdjustments()
that.resetScrollbar()
that.$element.trigger('hidden.bs.modal')
})
}
Modal.prototype.removeBackdrop = function () {
this.$backdrop && this.$backdrop.remove()
this.$backdrop = null
}
Modal.prototype.backdrop = function (callback) {
var that = this
var animate = this.$element.hasClass('fade') ? 'fade' : ''
if (this.isShown && this.options.backdrop) {
var doAnimate = $.support.transition && animate
this.$backdrop = $(document.createElement('div'))
.addClass('modal-backdrop ' + animate)
.appendTo(this.$body)
this.$element.on('click.dismiss.bs.modal', $.proxy(function (e) {
if (this.ignoreBackdropClick) {
this.ignoreBackdropClick = false
return
}
if (e.target !== e.currentTarget) return
this.options.backdrop == 'static'
? this.$element[0].focus()
: this.hide()
}, this))
if (doAnimate) this.$backdrop[0].offsetWidth // force reflow
this.$backdrop.addClass('in')
if (!callback) return
doAnimate ?
this.$backdrop
.one('bsTransitionEnd', callback)
.emulateTransitionEnd(Modal.BACKDROP_TRANSITION_DURATION) :
callback()
} else if (!this.isShown && this.$backdrop) {
this.$backdrop.removeClass('in')
var callbackRemove = function () {
that.removeBackdrop()
callback && callback()
}
$.support.transition && this.$element.hasClass('fade') ?
this.$backdrop
.one('bsTransitionEnd', callbackRemove)
.emulateTransitionEnd(Modal.BACKDROP_TRANSITION_DURATION) :
callbackRemove()
} else if (callback) {
callback()
}
}
// these following methods are used to handle overflowing modals
Modal.prototype.handleUpdate = function () {
this.adjustDialog()
}
Modal.prototype.adjustDialog = function () {
var modalIsOverflowing = this.$element[0].scrollHeight > document.documentElement.clientHeight
this.$element.css({
paddingLeft: !this.bodyIsOverflowing && modalIsOverflowing ? this.scrollbarWidth : '',
paddingRight: this.bodyIsOverflowing && !modalIsOverflowing ? this.scrollbarWidth : ''
})
}
Modal.prototype.resetAdjustments = function () {
this.$element.css({
paddingLeft: '',
paddingRight: ''
})
}
Modal.prototype.checkScrollbar = function () {
//window.innerWidth,瀏覽器的視口寬度，包含滾動(dòng)條的寬度
var fullWindowWidth = window.innerWidth
if (!fullWindowWidth) { // workaround for missing window.innerWidth in IE8
var documentElementRect = document.documentElement.getBoundingClientRect()
fullWindowWidth = documentElementRect.right - Math.abs(documentElementRect.left)
}
// document.body.clientWidth是瀏覽器窗口的寬度，不包括滾動(dòng)條
this.bodyIsOverflowing = document.body.clientWidth < fullWindowWidth
// 滾動(dòng)條的寬度
this.scrollbarWidth = this.measureScrollbar()
}
Modal.prototype.setScrollbar = function () {
var bodyPad = parseInt((this.$body.css('padding-right') || 0), 10)
this.originalBodyPad = document.body.style.paddingRight || ''
// 如果body，overflow，那么給body的padding-right加上滾動(dòng)條的寬度
if (this.bodyIsOverflowing) this.$body.css('padding-right', bodyPad + this.scrollbarWidth)
}
Modal.prototype.resetScrollbar = function () {
this.$body.css('padding-right', this.originalBodyPad)
}
Modal.prototype.measureScrollbar = function () { // thx walsh
var scrollDiv = document.createElement('div')
scrollDiv.className = 'modal-scrollbar-measure'
this.$body.append(scrollDiv)
// offsetWidth,對(duì)象整體的實(shí)際寬度，包括滾動(dòng)條等邊線
//clientWidth, 對(duì)象內(nèi)容的寬度，不包括滾動(dòng)條的寬度
var scrollbarWidth = scrollDiv.offsetWidth - scrollDiv.clientWidth
this.$body[0].removeChild(scrollDiv)
return scrollbarWidth
}
// MODAL PLUGIN DEFINITION
// =======================
function Plugin(option, _relatedTarget) {
// _relatedTarget觸發(fā)的按鈕或者a標(biāo)簽
// this是call函數(shù)指定的modal節(jié)點(diǎn)
// 遍歷頁(yè)面中的所有modal節(jié)點(diǎn)
return this.each(function () {
var $this = $(this)
var data = $this.data('bs.modal')
var options = $.extend({}, Modal.DEFAULTS, $this.data(), typeof option == 'object' && option)
// 如果data為空，那么給$(this).data('bs.modal')也就是data變量賦值,data變量現(xiàn)在是一個(gè)modal實(shí)例
if (!data) {
$this.data('bs.modal',
(data = new Modal(this, options))
)
}
// 如果option是string
if (typeof option == 'string') data[option](_relatedTarget)
// 如果show為真，那么調(diào)用show函數(shù)
else if (options.show) data.show(_relatedTarget)
})
}
var old = $.fn.modal
$.fn.modal = Plugin
$.fn.modal.Constructor = Modal
// MODAL NO CONFLICT
// =================
$.fn.modal.noConflict = function () {
$.fn.modal = old
return this
}
// MODAL DATA-API
// ==============
$(document).on('click.bs.modal.data-api', '[data-toggle="modal"]', function (e) {
var $this = $(this)
// 也就是觸發(fā)modal的元素（button、a）
var href = $this.attr('href')
var $target = $($this.attr('data-target') || (href && href.replace(/.*(?=#[^\s]+$)/, ''))) // strip for ie7
// 找到頁(yè)面中的modal節(jié)點(diǎn)
var option = $target.data('bs.modal') ? 'toggle' : $.extend({ remote: !/#/.test(href) && href }, $target.data(), $this.data())
if ($this.is('a')) e.preventDefault()
// 自定義事件'show.bs.modal',自定義事件只能通過(guò)on,one來(lái)‘綁定’
$target.one('show.bs.modal', function (showEvent) {
if (showEvent.isDefaultPrevented()) return // only register focus restorer if modal will actually get shown
$target.one('hidden.bs.modal', function () {
$this.is(':visible') && $this.trigger('focus')
})
})
Plugin.call($target, option, this)
// 這下Plugin里面的this指向的是$target
})
}(jQuery);
