From 1279c6766cd0404b5362af6fad864c96a2f00be5 Mon Sep 17 00:00:00 2001
From: Ian Gilman <ian@iangilman.com>
Date: Fri, 14 Nov 2014 17:19:04 -0800
Subject: [PATCH] More sequence mode work

---
 src/viewer.js                 | 35 +++++++++++++++++++----------------
 test/demo/collections/main.js | 12 ++++++------
 2 files changed, 25 insertions(+), 22 deletions(-)

diff --git a/src/viewer.js b/src/viewer.js
index 52583764..fa0afea7 100644
--- a/src/viewer.js
+++ b/src/viewer.js
@@ -200,13 +200,11 @@ $.Viewer = function( options ) {
         // how much we should be continuously zooming by
         "zoomFactor":        null,
         "lastZoomTime":      null,
-        // did we decide this viewer has a sequence of tile sources
-        "sequenced":         false,
-        "sequence":          0,
         "fullPage":          false,
         "onfullscreenchange": null
     };
 
+    this._sequenceIndex = 0;
     this._firstOpen = true;
     this._updateRequestId = null;
     this.currentOverlays = [];
@@ -507,17 +505,18 @@ $.Viewer = function( options ) {
 
     // Sequence mode
     if (this.sequenceMode) {
-        THIS[ this.hash ].sequenced = true;
-        this.initialPage = Math.max(0, Math.min(this.tileSources.length - 1, this.initialPage));
-        THIS[ this.hash ].sequence = this.initialPage;
+        if (this.tileSources && this.tileSources.length) {
+            this._sequenceIndex = Math.max(0, Math.min(this.tileSources.length - 1, this.initialPage));
+        }
+
         this.bindSequenceControls();
     }
 
     // Open initial tilesources
-    if ( this.tileSources ) {
+    if ( this.tileSources && this.tileSources.length) {
         if (this.sequenceMode) {
-            this.open(this.tileSources[this.initialPage]);
-            this._updateSequenceButtons( this.initialPage );
+            this.open(this.tileSources[this._sequenceIndex]);
+            this._updateSequenceButtons( this._sequenceIndex );
         } else {
             this.open( this.tileSources );
         }
@@ -1422,7 +1421,7 @@ $.extend( $.Viewer.prototype, $.EventSource.prototype, $.ControlDock.prototype,
             navImages               = this.navImages,
             useGroup                = true ;
 
-        if( this.showSequenceControl && THIS[ this.hash ].sequenced ){
+        if( this.showSequenceControl ){
 
             if( this.previousButton || this.nextButton ){
                 //if we are binding to custom buttons then layout and
@@ -1462,6 +1461,10 @@ $.extend( $.Viewer.prototype, $.EventSource.prototype, $.ControlDock.prototype,
                 this.previousButton.disable();
             }
 
+            if (!this.tileSources || !this.tileSources.length) {
+                this.nextButton.disable();
+            }
+
             if( useGroup ){
                 this.paging = new $.ButtonGroup({
                     buttons: [
@@ -1659,7 +1662,7 @@ $.extend( $.Viewer.prototype, $.EventSource.prototype, $.ControlDock.prototype,
      * @return {Number}
      */
     currentPage: function() {
-        return THIS[ this.hash ].sequence;
+        return this._sequenceIndex;
     },
 
     /**
@@ -1668,7 +1671,7 @@ $.extend( $.Viewer.prototype, $.EventSource.prototype, $.ControlDock.prototype,
      * @fires OpenSeadragon.Viewer.event:page
      */
     goToPage: function( page ){
-        if( page >= 0 && page < this.tileSources.length ){
+        if( this.tileSources && page >= 0 && page < this.tileSources.length ){
             /**
              * Raised when the page is changed on a viewer configured with multiple image sources (see {@link OpenSeadragon.Viewer#goToPage}).
              *
@@ -1681,7 +1684,7 @@ $.extend( $.Viewer.prototype, $.EventSource.prototype, $.ControlDock.prototype,
              */
             this.raiseEvent( 'page', { page: page } );
 
-            THIS[ this.hash ].sequence = page;
+            this._sequenceIndex = page;
 
             this._updateSequenceButtons( page );
 
@@ -1871,7 +1874,7 @@ $.extend( $.Viewer.prototype, $.EventSource.prototype, $.ControlDock.prototype,
     _updateSequenceButtons: function( page ) {
 
             if ( this.nextButton ) {
-                if( ( this.tileSources.length - 1 ) === page ) {
+                if(!this.tileSources || this.tileSources.length - 1 === page) {
                     //Disable next button
                     if ( !this.navPrevNextWrap ) {
                         this.nextButton.disable();
@@ -2856,7 +2859,7 @@ function onRotateRight() {
 
 
 function onPrevious(){
-    var previous = THIS[ this.hash ].sequence - 1;
+    var previous = this._sequenceIndex - 1;
     if(this.navPrevNextWrap && previous < 0){
         previous += this.tileSources.length;
     }
@@ -2865,7 +2868,7 @@ function onPrevious(){
 
 
 function onNext(){
-    var next = THIS[ this.hash ].sequence + 1;
+    var next = this._sequenceIndex + 1;
     if(this.navPrevNextWrap && next >= this.tileSources.length){
         next = 0;
     }
diff --git a/test/demo/collections/main.js b/test/demo/collections/main.js
index f026453e..cb34e807 100644
--- a/test/demo/collections/main.js
+++ b/test/demo/collections/main.js
@@ -32,12 +32,12 @@
 
             if (testInitialOpen) {
                 config.tileSources = [
-                    // {
-                    //     tileSource: "../../data/tall.dzi",
-                    //     x: 1.5,
-                    //     y: 0,
-                    //     width: 1
-                    // },
+                    {
+                        tileSource: "../../data/tall.dzi",
+                        x: 1.5,
+                        y: 0,
+                        width: 1
+                    },
                     {
                         tileSource: '../../data/wide.dzi',
                         opacity: 1,