From a6c85c7b337c32e8885aba8e683d96c5d924f846 Mon Sep 17 00:00:00 2001
From: Andy <andy@office>
Date: Thu, 5 Sep 2013 22:57:08 +0100
Subject: [PATCH 1/2] Added ability to specify a scrollable parent object

---
 jquery.appear.js | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/jquery.appear.js b/jquery.appear.js
index ff0b764..94e4731 100644
--- a/jquery.appear.js
+++ b/jquery.appear.js
@@ -13,11 +13,12 @@
 
   var check_binded = false;
   var check_lock = false;
+  var $window = $(window);
   var defaults = {
     interval: 250,
-    force_process: false
+    force_process: false,
+    scrolling_parent: $window
   }
-  var $window = $(window);
 
   var $prior_appeared;
 
@@ -76,7 +77,11 @@
           setTimeout(process, opts.interval);
         };
 
-        $(window).scroll(on_check).resize(on_check);
+        opts.scrolling_parent.scroll(on_check);
+        // resize event is only triggered for $window so no point setting it on scrolling_parent
+        // if scrolling_parent is resizeable you should make sure your resizing code calls .resize()
+        $window.resize(on_check);
+
         check_binded = true;
       }
 

From fa13b15c797a95c975292e87b2f760d78dbc499a Mon Sep 17 00:00:00 2001
From: Andy Smith <andy@apsmith.org>
Date: Tue, 29 Oct 2013 23:21:29 +0000
Subject: [PATCH 2/2] fixed for scrollable parent object

---
 jquery.appear.js | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/jquery.appear.js b/jquery.appear.js
index 94e4731..e88076f 100644
--- a/jquery.appear.js
+++ b/jquery.appear.js
@@ -21,6 +21,7 @@
   }
 
   var $prior_appeared;
+  var scrolling_parent;
 
   function process() {
     check_lock = false;
@@ -46,16 +47,15 @@
       return false;
     }
 
-    var window_left = $window.scrollLeft();
-    var window_top = $window.scrollTop();
     var offset = $element.offset();
-    var left = offset.left;
-    var top = offset.top;
+    // calculate pos of element relative to the visible part of the scrolling_parent
+    var left = offset.left - scrolling_parent.offset().left;
+    var top = offset.top - scrolling_parent.offset().top;
 
-    if (top + $element.height() >= window_top &&
-        top - ($element.data('appear-top-offset') || 0) <= window_top + $window.height() &&
-        left + $element.width() >= window_left &&
-        left - ($element.data('appear-left-offset') || 0) <= window_left + $window.width()) {
+    if ((top + $element.height() >= 0) &&
+        (top - ($element.data('appear-top-offset') || 0) <= scrolling_parent.height()) &&
+        (left + $element.width() >= 0) &&
+        (left - ($element.data('appear-left-offset') || 0) <= scrolling_parent.width())) {
       return true;
     } else {
       return false;
@@ -77,7 +77,8 @@
           setTimeout(process, opts.interval);
         };
 
-        opts.scrolling_parent.scroll(on_check);
+        scrolling_parent = opts.scrolling_parent;
+        scrolling_parent.scroll(on_check);
         // resize event is only triggered for $window so no point setting it on scrolling_parent
         // if scrolling_parent is resizeable you should make sure your resizing code calls .resize()
         $window.resize(on_check);