From f13691f60d0205a5b08abf42bb48b2c75ee05951 Mon Sep 17 00:00:00 2001
From: Larissa Smith <smithl@familysearch.org>
Date: Wed, 19 Aug 2015 13:29:55 -0600
Subject: [PATCH] Added option in addTiledImage to replace tiledImage at index.

---
 src/viewer.js | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/viewer.js b/src/viewer.js
index b0ee7757..7b482990 100644
--- a/src/viewer.js
+++ b/src/viewer.js
@@ -1193,6 +1193,10 @@ $.extend( $.Viewer.prototype, $.EventSource.prototype, $.ControlDock.prototype,
      *      named 'getTileUrl', it is treated as a custom TileSource.
      * @param {Number} [options.index] The index of the item. Added on top of
      * all other items if not specified.
+     * @param {Boolean} [options.replace=false] If true, the item at options.index will be
+     * removed and the new item is added in its place. options.tileSource will be
+     * interpreted and fetched if necessary before the old item is removed to avoid leaving
+     * a gap in the world.
      * @param {Number} [options.x=0] The X position for the image in viewport coordinates.
      * @param {Number} [options.y=0] The Y position for the image in viewport coordinates.
      * @param {Number} [options.width=1] The width for the image in viewport coordinates.
@@ -1216,6 +1220,8 @@ $.extend( $.Viewer.prototype, $.EventSource.prototype, $.ControlDock.prototype,
     addTiledImage: function( options ) {
         $.console.assert(options, "[Viewer.addTiledImage] options is required");
         $.console.assert(options.tileSource, "[Viewer.addTiledImage] options.tileSource is required");
+        $.console.assert(!options.replace || (options.index > -1 && options.index < this.world.getItemCount()),
+            "[Viewer.addTiledImage] if options.replace is used, options.index must be a valid index in Viewer.world");
 
         var _this = this;
 
@@ -1283,6 +1289,10 @@ $.extend( $.Viewer.prototype, $.EventSource.prototype, $.ControlDock.prototype,
 
                 _this._loadQueue.splice(0, 1);
 
+                if (queueItem.options.replace) {
+                    _this.world.removeItem(_this.world.getItemAt(queueItem.options.index));
+                }
+
                 tiledImage = new $.TiledImage({
                     viewer: _this,
                     source: queueItem.tileSource,