Prevent the page from jumping on tree tab change

IPython/html/static/tree/js/main.js

@@ -1,151 +1,162
 // Copyright (c) IPython Development Team.
 // Distributed under the terms of the Modified BSD License.
 
 require([
     'jquery',
     'base/js/namespace',
     'base/js/dialog',
     'base/js/events',
     'base/js/page',
     'base/js/utils',
     'services/config',
     'contents',
     'tree/js/notebooklist',
     'tree/js/clusterlist',
     'tree/js/sessionlist',
     'tree/js/kernellist',
     'tree/js/terminallist',
     'tree/js/newnotebook',
     'auth/js/loginwidget',
     // only loaded, not used:
     'jqueryui',
     'bootstrap',
     'custom/custom',
 ], function(
     $,
     IPython,
     dialog,
     events,
     page,
     utils,
     config,
     contents_service,
     notebooklist,
     clusterlist,
     sesssionlist,
     kernellist,
     terminallist,
     newnotebook,
     loginwidget){
     "use strict";
 
     page = new page.Page();
     
     var common_options = {
         base_url: utils.get_body_data("baseUrl"),
         notebook_path: utils.get_body_data("notebookPath"),
     };
     var cfg = new config.ConfigSection('tree', common_options);
     cfg.load();
     common_options.config = cfg;
     
     var session_list = new sesssionlist.SesssionList($.extend({
         events: events}, 
         common_options));
     var contents = new contents_service.Contents($.extend({
         events: events},
         common_options));
     var notebook_list = new notebooklist.NotebookList('#notebook_list', $.extend({
         contents: contents,
         session_list:  session_list}, 
         common_options));
     var cluster_list = new clusterlist.ClusterList('#cluster_list', common_options);
     var kernel_list = new kernellist.KernelList('#running_list',  $.extend({
         session_list:  session_list}, 
         common_options));
     
     var terminal_list;
     if (utils.get_body_data("terminalsAvailable") === "True") {
         terminal_list = new terminallist.TerminalList('#terminal_list', common_options);
     }
 
     var login_widget = new loginwidget.LoginWidget('#login_widget', common_options);
 
     var nnw = new newnotebook.NewNotebookWidget("#new-notebook-buttons",
         $.extend(
             {contents: contents},
             common_options
         )
     );
 
     var interval_id=0;
     // auto refresh every xx secondes, no need to be fast,
     //  update is done at least when page get focus
     var time_refresh = 60; // in sec
 
     var enable_autorefresh = function(){
         /**
          *refresh immediately , then start interval
          */
         session_list.load_sessions();
         cluster_list.load_list();
         if (terminal_list) {
             terminal_list.load_terminals();
         }
         if (!interval_id){
             interval_id = setInterval(function(){
                 session_list.load_sessions();
                 cluster_list.load_list();
                 if (terminal_list) {
                     terminal_list.load_terminals();
                 }
             }, time_refresh*1000);
         }
     };
 
     var disable_autorefresh = function(){
         clearInterval(interval_id);
         interval_id = 0;
     };
 
     // stop autorefresh when page lose focus
     $(window).blur(function() {
         disable_autorefresh();
     });
 
     //re-enable when page get focus back
     $(window).focus(function() {
         enable_autorefresh();
     });
 
     // finally start it, it will refresh immediately
     enable_autorefresh();
 
     page.show();
 
     // For backwards compatability.
     IPython.page = page;
     IPython.notebook_list = notebook_list;
     IPython.cluster_list = cluster_list;
     IPython.session_list = session_list;
     IPython.kernel_list = kernel_list;
     IPython.login_widget = login_widget;
     IPython.new_notebook_widget = nnw;
 
     events.trigger('app_initialized.DashboardApp');
     
     // bound the upload method to the on change of the file select list
     $("#alternate_upload").change(function (event){
         notebook_list.handleFilesUpload(event,'form');
     });
     
     // set hash on tab click
-    $("#tabs").find("a").click(function() {
-        window.location.hash = $(this).attr("href");
+    $("#tabs").find("a").click(function(e) {
+        // Prevent the document from jumping when the active tab is changed to a 
+        // tab that has a lot of content.
+        e.preventDefault();
+
+        // Set the hash without causing the page to jump.
+        // http://stackoverflow.com/a/14690177/2824256
+        var hash = $(this).attr("href");
+        if(window.history.pushState) {
+            window.history.pushState(null, null, hash);
+        } else {
+            window.location.hash = hash;
+        }
     });
     
     // load tab if url hash
     if (window.location.hash) {
         $("#tabs").find("a[href=" + window.location.hash + "]").click();
     }
 });