change scroll recording to handle different scroll elements between page changes

js/jquery.mobile.init.js

@@ -83,9 +83,14 @@
 			// define first page in dom case one backs out to the directory root (not always the first page visited, but defined as fallback)
 			$.mobile.firstPage = $pages.first();
 
+
 			// define page container
 			$.mobile.pageContainer = $pages.first().parent().addClass( "ui-mobile-viewport" );
 
+			// alert listeners that the pagecontainer has been determined for binding
+			// to events triggered on it
+			$window.trigger( "pagecontainercreate" );
+
 			// cue page loading message
 			$.mobile.showPageLoadingMsg();
 

js/jquery.mobile.navigation.js

@@ -399,54 +399,81 @@
 	}
 
 	// Save the last scroll distance per page, before it is hidden
-	var setLastScroll = function(){
-		if( setLastScrollEnabled ) {
-			return;
-		}
+	var setLastScrollEnabled = true, getScrollElem, setLastScroll;
 
-		var active = $.mobile.urlHistory.getActive(),
-			scrollElem = $window,
-			touchOverflow = $.support.touchOverflow && $.mobile.touchOverflowEnabled,
-			activePage;
+	getScrollElem = function() {
+		var scrollElem = $window, activePage,
+			touchOverflow = $.support.touchOverflow && $.mobile.touchOverflowEnabled;
 
 		if( touchOverflow ){
 			activePage = $( ".ui-page-active" );
 			scrollElem = activePage.is( ".ui-native-fixed" ) ? activePage.find( ".ui-content" ) : activePage;
 		}
 
-		if( active ){
+		return scrollElem;
+	};
+
+	setLastScroll = function( scrollElem ) {
+		// this barrier prevents setting the scroll value based on the browser
+		// scrolling the window based on a hashchange
+		if( !setLastScrollEnabled ) {
+			return;
+		}
+
+		var active = $.mobile.urlHistory.getActive();
+
+		if( active ) {
 			var lastScroll = scrollElem.scrollTop();
 
 			// Set active page's lastScroll prop.
-			// If the Y location we're scrolling to is less than minScrollBack, let it go.
+			// If the location we're scrolling to is less than minScrollBack, let it go.
 			active.lastScroll = lastScroll < $.mobile.minScrollBack ? $.mobile.defaultHomeScroll : lastScroll;
 		}
 	};
 
-	var setLastScrollEnabled = false;
-
 	// bind to scrollstop to gather scroll position. The delay allows for the hashchange
 	// event to fire and disable scroll recording in the case where the browser scrolls
 	// to the hash targets location (sometimes the top of the page). once pagechange fires
 	// getLastScroll is again permitted to operate
-	$( window ).bind( "scrollstop", function() {
-		setTimeout(setLastScroll, 100);
-	});
+	var firstScrollElem = getScrollElem(), handleSetLastScroll;
 
-	$( window ).bind( $.support.pushState ? "popstate" : "hashchange", function() {
-	 	setLastScrollEnabled = true;
-	});
+	handleSetLastScroll = function( opts ) {
+		setTimeout(setLastScroll, 100, opts.data.scrollElem );
+	};
 
-<<<<<<< HEAD
-	// to get last scroll, we need to get scrolltop before the page change
-	// using pagebeforechange or popstate/hashchange (whichever comes first)
-	$( document ).bind( "pagebeforechange", getLastScroll );
-	$( window ).bind( $.support.pushState ? "popstate" : "hashchange", getLastScroll );
-=======
-	$( window ).bind( "pagechange", function() {
+	// disable an scroll setting when a hashchange has been fired, this only works
+	// because the recording of the scroll position is delayed for 100ms after
+	// the browser might have changed the position because of the hashchange
+	$window.bind( $.support.pushState ? "popstate" : "hashchange", function() {
 	 	setLastScrollEnabled = false;
 	});
->>>>>>> use scrolltop to store scroll position
+
+	// handle initial hashchange from chrome :(
+	$window.one( $.support.pushState ? "popstate" : "hashchange", function() {
+		setLastScrollEnabled = true;
+	});
+
+	// wait until the mobile page container has been determined to bind to pagechange
+	$window.one( "pagecontainercreate", function(){
+		// once the page has changed, re-enable the scroll recording
+		$.mobile.pageContainer.bind( "pagechange", function() {
+			var scrollElem = getScrollElem();
+
+	 		setLastScrollEnabled = true;
+
+			// remove any binding that previously existed on the get scroll
+			// which may or may not be different than the scroll element determined for
+			// this page previously
+			scrollElem.unbind( "scrollstop", handleSetLastScroll);
+
+			// determine and bind to the current scoll element which may be the window
+			// or in the case of touch overflow the element with touch overflow
+			scrollElem.bind( "scrollstop", { scrollElem: scrollElem }, handleSetLastScroll);
+		});
+	});
+
+	// bind to scrollstop for the first page as "pagechange" won't befired in that case
+	firstScrollElem.bind( "scrollstop", { scrollElem: firstScrollElem }, handleSetLastScroll);
 
 	// Make the iOS clock quick-scroll work again if we're using native overflow scrolling
 	/*