jquery.sticky-kit.js

// Generated by CoffeeScript 1.9.2

/**
@license Sticky-kit v1.1.2 | WTFPL | Leaf Corcoran 2015 | http://leafo.net
 */

(function() {
  var $, win;

  $ = this.jQuery || window.jQuery;

  win = $(window);

  $.fn.stick_in_parent = function(opts) {
    var doc, elm, enable_bottoming, fn, i, inner_scrolling, len, manual_spacer, offset_top, parent_selector, recalc_every, sticky_class;
    if (opts == null) {
      opts = {};
    }
    sticky_class = opts.sticky_class, inner_scrolling = opts.inner_scrolling, recalc_every = opts.recalc_every, parent_selector = opts.parent, offset_top = opts.offset_top, manual_spacer = opts.spacer, enable_bottoming = opts.bottoming;
    if (offset_top == null) {
      offset_top = 0;
    }
    if (parent_selector == null) {
      parent_selector = void 0;
    }
    if (inner_scrolling == null) {
      inner_scrolling = true;
    }
    if (sticky_class == null) {
      sticky_class = "is_stuck";
    }
    doc = $(document);
    if (enable_bottoming == null) {
      enable_bottoming = true;
    }
    fn = function(elm, padding_bottom, parent_top, parent_height, top, height, el_float, detached) {
      var bottomed, detach, fixed, last_pos, last_scroll_height, offset, parent, recalc, recalc_and_tick, recalc_counter, spacer, tick;
      if (elm.data("sticky_kit")) {
        return;
      }
      elm.data("sticky_kit", true);
      last_scroll_height = doc.height();
      parent = elm.parent();
      if (parent_selector != null) {
        parent = parent.closest(parent_selector);
      }
      if (!parent.length) {
        throw "failed to find stick parent";
      }
      fixed = false;
      bottomed = false;
      spacer = manual_spacer != null ? manual_spacer && elm.closest(manual_spacer) : $("<div />");
      if (spacer) {
        spacer.css('position', elm.css('position'));
      }
      recalc = function() {
        var border_top, padding_top, restore;
        if (detached) {
          return;
        }
        last_scroll_height = doc.height();
        border_top = parseInt(parent.css("border-top-width"), 10);
        padding_top = parseInt(parent.css("padding-top"), 10);
        padding_bottom = parseInt(parent.css("padding-bottom"), 10);
        parent_top = parent.offset().top + border_top + padding_top;
        parent_height = parent.height();
        if (fixed) {
          fixed = false;
          bottomed = false;
          if (manual_spacer == null) {
            elm.insertAfter(spacer);
            spacer.detach();
          }
          elm.css({
            position: "",
            top: "",
            width: "",
            bottom: ""
          }).removeClass(sticky_class);
          restore = true;
        }
        top = elm.offset().top - (parseInt(elm.css("margin-top"), 10) || 0) - offset_top;
        height = elm.outerHeight(true);
        el_float = elm.css("float");
        if (spacer) {
          spacer.css({
            width: elm.outerWidth(true),
            height: height,
            display: elm.css("display"),
            "vertical-align": elm.css("vertical-align"),
            "float": el_float
          });
        }
        if (restore) {
          return tick();
        }
      };
      recalc();
      if (height === parent_height) {
        return;
      }
      last_pos = void 0;
      offset = offset_top;
      recalc_counter = recalc_every;
      tick = function() {
        var css, delta, recalced, scroll, will_bottom, win_height;
        if (detached) {
          return;
        }
        recalced = false;
        if (recalc_counter != null) {
          recalc_counter -= 1;
          if (recalc_counter <= 0) {
            recalc_counter = recalc_every;
            recalc();
            recalced = true;
          }
        }
        if (!recalced && doc.height() !== last_scroll_height) {
          recalc();
          recalced = true;
        }
        scroll = win.scrollTop();
        if (last_pos != null) {
          delta = scroll - last_pos;
        }
        last_pos = scroll;
        if (fixed) {
          if (enable_bottoming) {
            will_bottom = scroll + height + offset > parent_height + parent_top;
            if (bottomed && !will_bottom) {
              bottomed = false;
              elm.css({
                position: "fixed",
                bottom: "",
                top: offset
              }).trigger("sticky_kit:unbottom");
            }
          }
          if (scroll < top) {
            fixed = false;
            offset = offset_top;
            if (manual_spacer == null) {
              if (el_float === "left" || el_float === "right") {
                elm.insertAfter(spacer);
              }
              spacer.detach();
            }
            css = {
              position: "",
              width: "",
              top: ""
            };
            elm.css(css).removeClass(sticky_class).trigger("sticky_kit:unstick");
          }
          if (inner_scrolling) {
            win_height = win.height();
            if (height + offset_top > win_height) {
              if (!bottomed) {
                offset -= delta;
                offset = Math.max(win_height - height, offset);
                offset = Math.min(offset_top, offset);
                if (fixed) {
                  elm.css({
                    top: offset + "px"
                  });
                }
              }
            }
          }
        } else {
          if (scroll > top) {
            fixed = true;
            css = {
              position: "fixed",
              top: offset
            };
            css.width = elm.css("box-sizing") === "border-box" ? elm.outerWidth() + "px" : elm.width() + "px";
            elm.css(css).addClass(sticky_class);
            if (manual_spacer == null) {
              elm.after(spacer);
              if (el_float === "left" || el_float === "right") {
                spacer.append(elm);
              }
            }
            elm.trigger("sticky_kit:stick");
          }
        }
        if (fixed && enable_bottoming) {
          if (will_bottom == null) {
            will_bottom = scroll + height + offset > parent_height + parent_top;
          }
          if (!bottomed && will_bottom) {
            bottomed = true;
            if (parent.css("position") === "static") {
              parent.css({
                position: "relative"
              });
            }
            return elm.css({
              position: "absolute",
              bottom: padding_bottom,
              top: "auto"
            }).trigger("sticky_kit:bottom");
          }
        }
      };
      recalc_and_tick = function() {
        recalc();
        return tick();
      };
      detach = function() {
        detached = true;
        win.off("touchmove", tick);
        win.off("scroll", tick);
        win.off("resize", recalc_and_tick);
        $(document.body).off("sticky_kit:recalc", recalc_and_tick);
        elm.off("sticky_kit:detach", detach);
        elm.removeData("sticky_kit");
        elm.css({
          position: "",
          bottom: "",
          top: "",
          width: ""
        });
        parent.position("position", "");
        if (fixed) {
          if (manual_spacer == null) {
            if (el_float === "left" || el_float === "right") {
              elm.insertAfter(spacer);
            }
            spacer.remove();
          }
          return elm.removeClass(sticky_class);
        }
      };
      win.on("touchmove", tick);
      win.on("scroll", tick);
      win.on("resize", recalc_and_tick);
      $(document.body).on("sticky_kit:recalc", recalc_and_tick);
      elm.on("sticky_kit:detach", detach);
      return setTimeout(tick, 0);
    };
    for (i = 0, len = this.length; i < len; i++) {
      elm = this[i];
      fn($(elm));
    }
    return this;
  };

}).call(this);