slip.coffee

slip.coffee

Slip.js 0.2.0

! CopyRight: binnng http://github.com/binnng/slip.js
Licensed under: MIT
http://binnng.github.io/slip.js

¶

Fork me on Github!
```
((WIN, DOC) ->
```
¶

定义

缓存，便于变量名压缩

  UNDEFINED = undefined
  NULL = null

  X = "x"
  Y = "y"
  XY = "xy"

  LEFT = "left"
  RIGHT = "right"
  UP = "up"
  DOWN = "down"

¶

滑动方向中最小允许距离小于这个值不触发滑动
```
  MIN_ALLOW_DISTANCE = 10
```
¶

如果是单方向滑动非滑动方向最大允许距离
```
  MAX_OPP_ALLOW_DISTANCE = 40
```

CSS的前缀

  CSS_PREFIX_MAP = [
    "webkit"
    "moz"
    "ms"
    "o"
    ""
  ]

¶

从一串包含数字的字符串中提取数字用于在css值中提取偏移值
```
transform: translate(-270px, 180px, 0);
```
```
  NUMBER_REG = /\-?[0-9]+\.?[0-9]*/g
```
¶

是不是触屏设备如果是触屏设备使用touch事件，否则使用mouse事件
```
  IsTouch = 'ontouchend' of WIN
```

定义开始，进行，结束的事件名

  START_EVENT = if IsTouch then 'touchstart' else 'mousedown'
  MOVE_EVENT = if IsTouch then 'touchmove' else 'mousemove'
  END_EVENT = if IsTouch then 'touchend' else 'mouseup'

WINDOW_HEIGHT WINDOW_WIDTH

浏览器窗口的高度，宽度

  WINDOW_HEIGHT = WIN['innerHeight']
  WINDOW_WIDTH = WIN['innerWidth']

¶

noop

空函数作为默认的回调函数
```
  noop = ->
```
¶

方法

setTransition

设置css的transition

ele: 原生的dom元素
css: transition的值

  setTransition = (ele, css) ->
    for prefix in CSS_PREFIX_MAP
      name = if prefix then "#{prefix}Transition" else "transition"
      ele.style[name] = css

setTranslate

设置元素的CSS位移

ele: 原生的DOM元素
x|y|z: 偏移的x, y, z

  setTranslate = (ele, x, y, z) ->
    for prefix in CSS_PREFIX_MAP
      name = if prefix then "#{prefix}Transform" else "transform"
      ele.style[name] = "translate3d(#{x or 0}px, #{y or 0}px, #{z or 0}px)"

getTranslate

获取元素的translate值

ele: 原生的dom元素

  getTranslate = (ele) ->

    translate = []
    css = ''
    coord = ''

    for prefix in CSS_PREFIX_MAP
      name = if prefix then "#{prefix}Transform" else "transform"

      css = ele.style[name]

      if css and typeof css is 'string'
        coord = css.match(/\((.*)\)/g)[0]
        translate = coord and coord.match NUMBER_REG
        break

    if translate.length
      x: translate[0] or 0
      y: translate[1] or 0
      z: translate[2] or 0

¶

Slip类
¶

class Slip

核心的Slip构造函数
```
  class Slip
```
¶

获取事件触发距离处理一堆兼容
```
    getCoordinatesArray = [
```

移动端设备

      (event) ->
        touches = event.touches and ((if event.touches.length then event.touches else [event]))
        e = (event.changedTouches and event.changedTouches[0]) or (event.originalEvent and event.originalEvent.changedTouches and event.originalEvent.changedTouches[0]) or touches[0].originalEvent or touches[0]
        "x": e.clientX
        "y": e.clientY

pc设备

      (event) ->
        e = event
        "x": e.clientX
        "y": e.clientY
    ]

    getCoordinates = if IsTouch then getCoordinatesArray[0] else getCoordinatesArray[1]

¶

构造器
- ele: 原生的dom元素，定义可以被滑动的元素
- direction: 可被滑动的方向，有三个合法值'x', 'y', 'xy'，默认为 'x'
```
    constructor: (@ele, @direction) ->
```
¶

是不是被按下了，只有按下才允许移动
```
      @_isPressed = no
```

开始的回调
移动中回调
结束的回调

      @onStart = @onMove = @onEnd = noop

¶
- coord: 元素实际坐标值
- eventCoords: 手指的坐标，用于在各种事件中传递
- cacheCoords: 当touchstart时候，缓存的当前位移，用于touchmove中计算
- finger: 手指的位移
- absFinger: 手指位移的绝对值
```
      @coord = @eventCoords = @cacheCoords = @finger = @absFinger = NULL
```
¶

结束后手指滑动的方向

这个值是个数组
- 左滑: ['left']
- 右滑: ['right']
- 上滑: ['up']
- 下滑: ['down']
- 左上滑: ['left', 'up']
- 右上滑: ['right', 'up']
- 右下滑: ['right', 'down']
- 左下滑: ['left', 'down']
```
      @orient = []
```
¶

slider
```
      @isSlider = no
```
¶

webapp当前页只有设置webapp才有值
```
      @isWebapp = no
```

默认的滑屏过渡时间，单位为ms 这个值可以通过time方法来重置

// 设置过度时间为200ms
Slip(ele, 'y').time(200);

      @duration = "400"

当前第几页从0开始

      @page = 0

    start : (fn) -> (@onStart = fn) and @
    move  : (fn) -> (@onMove  = fn) and @
    end   : (fn) -> (@onEnd   = fn) and @

Slip(ele).setCoord(…)

设置元素坐标如果元素初始化就有一定的偏移，就可以使用这个方法

userCoords: 一个坐标对象

Slip(ele, 'x')
.setCoord({
  x: 100,
  y: 0,
  z: 0
});

    setCoord: (userCoords) ->
      coords = @coord = 
        "x": userCoords[X] or 0
        "y": userCoords[Y] or 0

      ele = @ele

      setTranslate ele, coords[X], coords[Y]
      ele.setAttribute attr, coords[attr] for attr of coords

      @

触摸开始的回调

    onTouchStart: (event) ->
      @_isPressed = yes

      @eventCoords = getCoordinates event

      @cacheCoords = @coord

清空手指位移

      @finger = @absFinger = NULL

      @onSliderStart event if @isSlider
      ret = @onStart.apply @, [event]

触摸进行中的回调

    onTouchMove: (event) ->
      event.preventDefault()

      return no unless @_isPressed

      moveCoords = getCoordinates event

      direction = @direction

手指偏移

左滑 finger.x < 0
右滑 finger.x > 0
上滑 finger.y < 0
下滑 finger.y > 0

      finger = @finger = 
        x: moveCoords.x - @eventCoords.x
        y: moveCoords.y - @eventCoords.y

手指偏移的绝对值

      absFinger = @absFinger = 
        x: Math.abs finger.x
        y: Math.abs finger.y

¶

单方向滑动时，小于正方向最小距离，大于反方向最大距离，不是正确的手指行为
```
      if direction isnt XY
```

反方向

        oppDirection = if direction is X then Y else X

        if absFinger[direction] < MIN_ALLOW_DISTANCE or absFinger[oppDirection] > MAX_OPP_ALLOW_DISTANCE
          return no

手指移动方向

      orient = []
      if absFinger.x > MIN_ALLOW_DISTANCE
        orient.push if finger.x < 0 then LEFT else RIGHT

      if absFinger.y > MIN_ALLOW_DISTANCE
        orient.push if finger.y < 0 then UP else DOWN

      @orient = orient

¶

执行用户定义的进行中回调用户定义回调可以有返回值如果返回值为false，那就不继续了
```
      ret = @onMove.apply @, [event]

      return no if ret is no

      ele = @ele
```

元素的实际位移

      eleMove = @coord = 
        "x": if direction.indexOf(X) < 0 then @cacheCoords[X] else @cacheCoords[X] - 0 + finger.x
        "y": if direction.indexOf(Y) < 0 then @cacheCoords[Y] else @cacheCoords[Y] - 0 + finger.y

      setTranslate ele, eleMove[X], eleMove[Y]

在元素上标记位移

      ele.setAttribute attr, eleMove[attr] for attr of eleMove

触摸结束的回调

    onTouchEnd: (event) ->
      @_isPressed = no

      ele = @ele

      @onSliderEnd event if @isSlider
      ret = @onEnd.apply @, [event]

¶

结束后设置一次translate 防止用户在自己定义的回调中改变了translate的值
```
      trans = getTranslate @ele
      @setCoord trans if trans
```

最后来清空手指滑动的方向

      @orient = []

    onSliderStart: (event) ->
      setTransition @ele, NULL

¶

当滑动结束时，针对轮播器做些特别处理
```
    onSliderEnd: (event) ->
```

手指滑动的方向

      orient = @orient.join ""

      page = @page
      pageNum = @pageNum
      ele = @ele
      duration = @duration
      absFinger = @absFinger

是不是垂直滑动

      isVerticalWebapp = @direction is Y

      isUp = orient.indexOf(UP) > -1
      isDown = orient.indexOf(DOWN) > -1
      isLeft = orient.indexOf(LEFT) > -1
      isRight = orient.indexOf(RIGHT) > -1

      if isVerticalWebapp
        page++ if isUp
        page-- if isDown
      else 
        page++ if isLeft
        page-- if isRight

归位超出的页数

      if page is pageNum
        page = pageNum - 1

      if page is -1
        page = 0

      @jump page

初始化

    init: -> 
      @coord = "x": 0, "y": 0

之所以加上下划线方法，是为了给 destroy 用

      onTouchStart = @_onTouchStart = (event) => @onTouchStart event
      onTouchMove = @_onTouchMove = (event) => @onTouchMove event
      onTouchEnd = @_onTouchEnd= (event) => @onTouchEnd event

      ele = @ele
      ele.addEventListener START_EVENT, onTouchStart, no
      ele.addEventListener MOVE_EVENT, onTouchMove, no
      ele.addEventListener END_EVENT, onTouchEnd, no

初始化元素位移

      initMove = @coord = "x": 0, "y": 0

      direction = @direction
      setTranslate ele, initMove[X], initMove[Y]

      ele.setAttribute attr, initMove[attr] for attr of initMove

      @

Slip(ele).destroy()

摧毁元素的滑动

    destroy: ->

      ele = @ele
      ele.removeEventListener START_EVENT, @_onTouchStart, no
      ele.removeEventListener MOVE_EVENT, @_onTouchMove, no
      ele.removeEventListener END_EVENT, @_onTouchEnd, no

      @

¶

Slip(ele).slider()

设置是个普通的轮播器 elPages: 可接受三种类型的值
1. String: 传入一个选择器
2. Array|类Array的Obejct: 子元素列表
3. undifined|null… 传入空值，那就默认获取滑动元素的所有直接子元素（儿子）。
推荐第二种做法。
```
    slider: (elPages)->
      ele = @ele
```

如果传入了选择器

      if typeof elPages is "string"
        elPages = ele.querySelectorAll(elPages)

传入为空

      else if not elPages
        elPages = []
        elChilds = ele.childNodes

        for elChild in elChilds
          elPages.push elChild if elChild.nodeType is 1

      @isSlider = yes
      @page = 0
      @elPages = elPages

      elPagesLen = elPages.length
      pageNum = @pageNum = if elPagesLen then elPagesLen else 0

横向滑动

      if @direction is X
        elPage.style.cssFloat = LEFT for elPage in elPages

      @

¶

Slip(ele).webapp()

设置页面是个全屏的webapp 继承了slider，再做些特别处理。
```
    webapp: (elPages) ->
      @isWebapp = yes
```

如果是webapp肯定全屏

      @.slider(elPages).fullscreen()

      elPages = @elPages
      ele = @ele
      pageNum = @pageNum

      ele.style.height = "#{WINDOW_HEIGHT * pageNum}px"
      @height WINDOW_HEIGHT

横向滑动的webapp

      @width WINDOW_WIDTH if @direction is X
      
      @

Slip(ele).slider().height(200)

设置轮播器的高度

    height: (num)->
      ele = @ele
      elPages = @elPages
      pageNum = @pageNum
      num = String(num).replace "px", ""

      if num is "100%"
        num = WINDOW_HEIGHT

      @pageHeight = num

      if @direction is X
        ele.style.height = "#{num}px"

      elPage.style.height = "#{num}px" for elPage in elPages

      @

Slip(ele).slider().width(‘100%’);

设置轮播器的宽度

    width: (num)->
      ele = @ele
      elPages = @elPages
      pageNum = @pageNum
      num = String(num).replace "px", ""

      if num is "100%"
        num = WINDOW_WIDTH

      @pageWidth = num

      if @direction is X
        ele.style.width = "#{num * pageNum}px"

      elPage.style.width = "#{num}px" for elPage in elPages

      @

Slip(ele).fullscreen()

设置全屏

    fullscreen: ->

      ele = @ele
      child = ele

      while parent = child.parentNode

        if parent.nodeType is 1
          parent.style.height = "100%"
          parent.style.overflow = "hidden"

        child = parent

      @

Slip(ele).webapp().time(200)

设置轮播时页面切换的过渡时长

    time: (duration) ->
      @duration = String(duration).replace "ms", ""

      @

¶

jump(page)

跳转到第几页
```
    jump: (page) ->
```

手指滑动的方向

      orient = @orient.join ""

      trans = 0

是不是超出了，即第一页向前滑，最后一页向后滑

      isOut = no

      ele = @ele
      pageNum = @pageNum
      duration = @duration
      absFinger = @absFinger or "x": 0, "y": 0

是不是垂直滑动

      isVerticalWebapp = @direction is Y


      if page > pageNum - 1
        page = pageNum - 1

      if page < 0
        page = 0

归位超出的页数

      if page is pageNum - 1
        isOut = yes

      if page is 0
        isOut = yes

这里做了个细节处理

当用户定义整页滑动的时长为400ms
如果在超出时，反弹回去的时间不应为400ms
反弹的距离 < 页面的距离
所以反弹的时长 = 整页的时长 * (反弹的距离 / 整页的距离)
即反弹的时长 < 整页过渡的时长

恩，这叫情怀

      if isOut is yes
        duration *= if isVerticalWebapp then absFinger[Y] / @pageHeight else absFinger[X] / @pageWidth
        
      setTransition ele, "all #{duration}ms ease-in"

      if isVerticalWebapp
        trans = "-#{page * @pageHeight}"
        setTranslate ele, 0, trans, 0
      else
        trans = "-#{page * @pageWidth}"
        setTranslate ele, trans, 0, 0

      @page = page
      
      trans = getTranslate @ele
      @setCoord trans if trans

slip 暴露到window的对象，内部实例化Slip

  entry = (ele, direction) ->
    instance = new Slip ele, direction or X
    instance.init()

  if typeof define is "function"
    define "binnng/slip.js", (require, exports, module) ->
      entry

  else
    WIN["Slip"] = entry

) window, document

slip.coffee

定义

WINDOW_HEIGHT WINDOW_WIDTH

noop

方法

setTransition

setTranslate

getTranslate

Slip类

class Slip

Slip(ele).setCoord(…)

Slip(ele).destroy()

Slip(ele).slider()

Slip(ele).webapp()

Slip(ele).slider().height(200)

Slip(ele).slider().width(‘100%’);

Slip(ele).fullscreen()

Slip(ele).webapp().time(200)

jump(page)