don't stop propagation in dashboard

Stopping click propagation should be avoided when used as a hack
for something else, as it interacts poorly with the open/close
mechanics of Bootstrap menus (amongst others).
(more [here](http://css-tricks.com/dangers-stopping-event-propagation/)

This code preserves the intended behaviour (toggling the checkbox when
clicking on the row, except for the link) without resorting to
`stopPropagation()`

IPython/html/static/tree/js/notebooklist.js

@@ -1,896 +1,891 b''
 // Copyright (c) IPython Development Team.
 // Distributed under the terms of the Modified BSD License.
 
 define([
     'base/js/namespace',
     'jquery',
     'base/js/utils',
     'base/js/dialog',
     'base/js/events',
     'base/js/keyboard',
 ], function(IPython, $, utils, dialog, events, keyboard) {
     "use strict";
     
     var NotebookList = function (selector, options) {
         /**
          * Constructor
          *
          * Parameters:
          *  selector: string
          *  options: dictionary
          *      Dictionary of keyword arguments.
          *          session_list: SessionList instance
          *          element_name: string
          *          base_url: string
          *          notebook_path: string
          *          contents: Contents instance
          */
         var that = this;
         this.session_list = options.session_list;
         // allow code re-use by just changing element_name in kernellist.js
         this.element_name = options.element_name || 'notebook';
         this.selector = selector;
         if (this.selector !== undefined) {
             this.element = $(selector);
             this.style();
             this.bind_events();
         }
         this.notebooks_list = [];
         this.sessions = {};
         this.base_url = options.base_url || utils.get_body_data("baseUrl");
         this.notebook_path = options.notebook_path || utils.get_body_data("notebookPath");
         this.contents = options.contents;
         if (this.session_list && this.session_list.events) {
             this.session_list.events.on('sessions_loaded.Dashboard', 
                 function(e, d) { that.sessions_loaded(d); });
         }
         this.selected = [];
     };
 
     NotebookList.prototype.style = function () {
         var prefix = '#' + this.element_name;
         $(prefix + '_toolbar').addClass('list_toolbar');
         $(prefix + '_list_info').addClass('toolbar_info');
         $(prefix + '_buttons').addClass('toolbar_buttons');
         $(prefix + '_list_header').addClass('list_header');
         this.element.addClass("list_container");
     };
 
     NotebookList.prototype.bind_events = function () {
         var that = this;
         $('#refresh_' + this.element_name + '_list').click(function () {
             that.load_sessions();
         });
         this.element.bind('dragover', function () {
             return false;
         });
         this.element.bind('drop', function(event){
             that.handleFilesUpload(event,'drop');
             return false;
         });
 
         // Bind events for singleton controls.
         if (!NotebookList._bound_singletons) {
             NotebookList._bound_singletons = true;
             $('#new-file').click(function(e) {
                 var w = window.open();
                 that.contents.new_untitled(that.notebook_path || '', {type: 'file', ext: '.txt'}).then(function(data) {
                     var url = utils.url_join_encode(
                         that.base_url, 'edit', data.path
                     );
                     w.location = url;
                 }).catch(function (e) {
                     w.close();
                     dialog.modal({
                         title: 'Creating File Failed',
                         body: $('<div/>')
                             .text("An error occurred while creating a new file.")
                             .append($('<div/>')
                                 .addClass('alert alert-danger')
                                 .text(e.message || e)),
                         buttons: {
                             OK: {'class': 'btn-primary'}
                         }
                     });
                 });
                 that.load_sessions();
             });
             $('#new-folder').click(function(e) {
                 that.contents.new_untitled(that.notebook_path || '', {type: 'directory'})
                 .then(function(){
                     that.load_list();
                 }).catch(function (e) {
                     dialog.modal({
                         title: 'Creating Folder Failed',
                         body: $('<div/>')
                             .text("An error occurred while creating a new folder.")
                             .append($('<div/>')
                                 .addClass('alert alert-danger')
                                 .text(e.message || e)),
                         buttons: {
                             OK: {'class': 'btn-primary'}
                         }
                     });
                 });
                 that.load_sessions();
             });
 
             // Bind events for action buttons.
             $('.rename-button').click($.proxy(this.rename_selected, this));
             $('.shutdown-button').click($.proxy(this.shutdown_selected, this));
             $('.duplicate-button').click($.proxy(this.duplicate_selected, this));
             $('.delete-button').click($.proxy(this.delete_selected, this));
 
             // Bind events for selection menu buttons.
             $('#tree-selector .select-all').click($.proxy(this.select_all, this));
             $('#tree-selector .select-notebooks').click($.proxy(this.select_notebooks, this));
             $('#tree-selector .select-running-notebooks').click($.proxy(this.select_running_notebooks, this));
             $('#tree-selector .select-files').click($.proxy(this.select_files, this));
             $('#tree-selector .select-directories').click($.proxy(this.select_directories, this));
             $('#tree-selector .deselect-all').click($.proxy(this.deselect_all, this));
         }
     };
 
     NotebookList.prototype.handleFilesUpload =  function(event, dropOrForm) {
         var that = this;
         var files;
         if(dropOrForm =='drop'){
             files = event.originalEvent.dataTransfer.files;
         } else 
         {
             files = event.originalEvent.target.files;
         }
         for (var i = 0; i < files.length; i++) {
             var f = files[i];
             var name_and_ext = utils.splitext(f.name);
             var file_ext = name_and_ext[1];
 
             var reader = new FileReader();
             if (file_ext === '.ipynb') {
                 reader.readAsText(f);
             } else {
                 // read non-notebook files as binary
                 reader.readAsArrayBuffer(f);
             }
             var item = that.new_item(0, true);
             item.addClass('new-file');
             that.add_name_input(f.name, item, file_ext == '.ipynb' ? 'notebook' : 'file');
             // Store the list item in the reader so we can use it later
             // to know which item it belongs to.
             $(reader).data('item', item);
             reader.onload = function (event) {
                 var item = $(event.target).data('item');
                 that.add_file_data(event.target.result, item);
                 that.add_upload_button(item);
             };
             reader.onerror = function (event) {
                 var item = $(event.target).data('item');
                 var name = item.data('name');
                 item.remove();
                 dialog.modal({
                     title : 'Failed to read file',
                     body : "Failed to read file '" + name + "'",
                     buttons : {'OK' : { 'class' : 'btn-primary' }}
                 });
             };
         }
         // Replace the file input form wth a clone of itself. This is required to
         // reset the form. Otherwise, if you upload a file, delete it and try to 
         // upload it again, the changed event won't fire.
         var form = $('input.fileinput');
         form.replaceWith(form.clone(true));
         return false;
     };
 
     NotebookList.prototype.clear_list = function (remove_uploads) {
         /**
          * Clears the navigation tree.
          *
          * Parameters
          * remove_uploads: bool=False
          *      Should upload prompts also be removed from the tree.
          */
         if (remove_uploads) {
             this.element.children('.list_item').remove();
         } else {
             this.element.children('.list_item:not(.new-file)').remove();  
         }
     };
 
     NotebookList.prototype.load_sessions = function(){
         this.session_list.load_sessions();
     };
 
 
     NotebookList.prototype.sessions_loaded = function(data){
         this.sessions = data;
         this.load_list();
     };
 
     NotebookList.prototype.load_list = function () {
         var that = this;
         this.contents.list_contents(that.notebook_path).then(
             $.proxy(this.draw_notebook_list, this),
             function(error) {
                 that.draw_notebook_list({content: []}, "Server error: " + error.message);
             }
         );
     };
 
     /**
      * Draw the list of notebooks
      * @method draw_notebook_list
      * @param {Array} list An array of dictionaries representing files or
      *     directories.
      * @param {String} error_msg An error message
      */
 
 
     var type_order = {'directory':0,'notebook':1,'file':2};
 
     NotebookList.prototype.draw_notebook_list = function (list, error_msg) {
         // Remember what was selected before the refresh.
         var selected_before = this.selected;
 
         list.content.sort(function(a, b) {
             if (type_order[a['type']] < type_order[b['type']]) {
                 return -1;
             }
             if (type_order[a['type']] > type_order[b['type']]) {
                 return 1;
             }
             if (a['name'] < b['name']) {
                 return -1;
             }
             if (a['name'] > b['name']) {
                 return 1;
             }
             return 0;
         });
         var message = error_msg || 'Notebook list empty.';
         var item = null;
         var model = null;
         var len = list.content.length;
         this.clear_list();
         var n_uploads = this.element.children('.list_item').length;
         if (len === 0) {
             item = this.new_item(0);
             var span12 = item.children().first();
             span12.empty();
             span12.append($('<div style="margin:auto;text-align:center;color:grey"/>').text(message));
         }
         var path = this.notebook_path;
         var offset = n_uploads;
         if (path !== '') {
             item = this.new_item(offset, false);
             model = {
                 type: 'directory',
                 name: '..',
                 path: utils.url_path_split(path)[0],
             };
             this.add_link(model, item);
             offset += 1;
         }
         for (var i=0; i<len; i++) {
             model = list.content[i];
             item = this.new_item(i+offset, true);
             this.add_link(model, item);
         }
         // Trigger an event when we've finished drawing the notebook list.
         events.trigger('draw_notebook_list.NotebookList');
 
         // Reselect the items that were selected before.  Notify listeners
         // that the selected items may have changed.  O(n^2) operation.
         selected_before.forEach(function(item) {
             var list_items = $('.list_item');
             for (var i=0; i<list_items.length; i++) {
                 var $list_item = $(list_items[i]);
                 if ($list_item.data('path') == item.path) {
                     $list_item.find('input[type=checkbox]').prop('checked', true);
                     break;
                 }
             }
         });
         this._selection_changed();  
     };
 
 
     /**
      * Creates a new item.
      * @param  {integer} index
      * @param  {boolean} [selectable] - tristate, undefined: don't draw checkbox,
      *                                  false: don't draw checkbox but pad
      *                                  where it should be, true: draw checkbox.
      * @return {JQuery} row
      */
     NotebookList.prototype.new_item = function (index, selectable) {
         var row = $('<div/>')
             .addClass("list_item")
             .addClass("row");
 
         var item = $("<div/>")
             .addClass("col-md-12")
             .appendTo(row);
 
         var checkbox;
         if (selectable !== undefined) {
             checkbox = $('<input/>')
                 .attr('type', 'checkbox')
                 .attr('title', 'Click here to rename, delete, etc.')
                 .appendTo(item);
         }
 
         $('<i/>')
             .addClass('item_icon')
             .appendTo(item);
 
         var link = $("<a/>")
             .addClass("item_link")
             .appendTo(item);
 
         $("<span/>")
             .addClass("item_name")
             .appendTo(link);
         
         if (selectable === false) {
             checkbox.css('visibility', 'hidden');
         } else if (selectable === true) {
             var that = this;
-            link.click(function(e) {
-                e.stopPropagation();
-            });
-            checkbox.click(function(e) {
-                e.stopPropagation();
-                that._selection_changed();
-            });
             row.click(function(e) {
-                e.stopPropagation();
-                checkbox.prop('checked', !checkbox.prop('checked'));
+                // toggle checkbox only if the click doesn't come from the checkbox or the link
+                if (!$(e.target).is('span[class=item_name]') && !$(e.target).is('input[type=checkbox]')) {
+                    checkbox.prop('checked', !checkbox.prop('checked'));
+                }
                 that._selection_changed();
             });
         }
 
         var buttons = $('<div/>')
             .addClass("item_buttons  pull-right")
             .appendTo(item);
 
         $('<div/>')
             .addClass('running-indicator')
             .text('Running')
             .css('visibility', 'hidden')
             .appendTo(buttons);
         
         if (index === -1) {
             this.element.append(row);
         } else {
             this.element.children().eq(index).after(row);
         }
         return row;
     };
 
 
     NotebookList.icons = {
         directory: 'folder_icon',
         notebook: 'notebook_icon',
         file: 'file_icon',
     };
 
     NotebookList.uri_prefixes = {
         directory: 'tree',
         notebook: 'notebooks',
         file: 'edit',
     };
 
     /**
      * Select all of the items in the tree.
      */
     NotebookList.prototype.select_all = function() {
         $('.list_item input[type=checkbox]').each(function(index, item) {
             $(item).prop('checked', true);
         });
         this._selection_changed();
     };
 
     /**
      * Select all of the notebooks in the tree.
      */
     NotebookList.prototype.select_notebooks = function() {
         this.deselect_all();
         $('.list_item').each(function(index, item) {
             if ($(item).data('type') === 'notebook') {
                 $(item).find('input[type=checkbox]').prop('checked', true);
             }
         });
         this._selection_changed();
     };
 
     /**
      * Select all of the running notebooks in the tree.
      */
     NotebookList.prototype.select_running_notebooks = function() {
         this.deselect_all();
         var that = this;
         $('.list_item').each(function(index, item) {
             if ($(item).data('type') === 'notebook' && that.sessions[$(item).data('path')] !== undefined) {
                 $(item).find('input[type=checkbox]').prop('checked', true);
             }
         });
         this._selection_changed();
     };
 
     /**
      * Select all of the files in the tree.
      */
     NotebookList.prototype.select_files = function() {
         this.deselect_all();
         $('.list_item').each(function(index, item) {
             if ($(item).data('type') === 'file') {
                 $(item).find('input[type=checkbox]').prop('checked', true);
             }
         });
         this._selection_changed();
     };
 
     /**
      * Select all of the directories in the tree.
      */
     NotebookList.prototype.select_directories = function() {
         this.deselect_all();
         $('.list_item').each(function(index, item) {
             if ($(item).data('type') === 'directory') {
                 $(item).find('input[type=checkbox]').prop('checked', true);
             }
         });
         this._selection_changed();
     };
 
     /**
      * Unselect everything selected in the tree.
      */
     NotebookList.prototype.deselect_all = function() {
         $('.list_item input[type=checkbox]').each(function(index, item) {
             $(item).prop('checked', false);
         });
         this._selection_changed();
     };
 
 
     /**
      * Handles when any row selector checkbox is toggled.
      */
     NotebookList.prototype._selection_changed = function() {
         // Use a JQuery selector to find each row with a checked checkbox.  If
         // we decide to add more checkboxes in the future, this code will need
         // to be changed to distinguish which checkbox is the row selector.
         var selected = [];
         var has_running_notebook = false;
         var has_directory = false;
         var has_file = false;
         var that = this;
         var checked = 0;
         $('.list_item :checked').each(function(index, item) {
             var parent = $(item).parent().parent();
 
             // If the item doesn't have an upload button and it's not the 
             // breadcrumbs, it can be selected.  Breadcrumbs path == ''.
             if (parent.find('.upload_button').length === 0 && parent.data('path') !== '') {
                 checked++;
                 selected.push({
                     name: parent.data('name'), 
                     path: parent.data('path'), 
                     type: parent.data('type')
                 });
 
                 // Set flags according to what is selected.  Flags are later
                 // used to decide which action buttons are visible.
                 has_running_notebook = has_running_notebook || 
                     (parent.data('type') == 'notebook' && that.sessions[parent.data('path')] !== undefined);
                 has_file = has_file || parent.data('type') == 'file';
                 has_directory = has_directory || parent.data('type') == 'directory';    
             }
         });
         this.selected = selected;
 
         // Rename is only visible when one item is selected.
         if (selected.length==1) {
             $('.rename-button').css('display', 'inline-block');
         } else {
             $('.rename-button').css('display', 'none');
         }
 
         // Shutdown is only visible when one or more notebooks running notebooks
         // are selected and no non-notebook items are selected.
         if (has_running_notebook && !(has_file || has_directory)) {
             $('.shutdown-button').css('display', 'inline-block');
         } else {
             $('.shutdown-button').css('display', 'none');
         }
 
         // Duplicate isn't visible when a directory is selected.
         if (selected.length > 0 && !has_directory) {
             $('.duplicate-button').css('display', 'inline-block');
         } else {
             $('.duplicate-button').css('display', 'none');
         }
 
         // Delete is visible if one or more items are selected.
         if (selected.length > 0) {
             $('.delete-button').css('display', 'inline-block');
         } else {
             $('.delete-button').css('display', 'none');
         }
 
         // If all of the items are selected, show the selector as checked.  If
         // some of the items are selected, show it as checked.  Otherwise,
         // uncheck it.
         var total = 0;
         $('.list_item input[type=checkbox]').each(function(index, item) {
             var parent = $(item).parent().parent();
             // If the item doesn't have an upload button and it's not the 
             // breadcrumbs, it can be selected.  Breadcrumbs path == ''.
             if (parent.find('.upload_button').length === 0 && parent.data('path') !== '') {
                 total++;
             }
         });
         if (checked === 0) {
             $('#tree-selector input[type=checkbox]')[0].indeterminate = false;
             $('#tree-selector input[type=checkbox]').prop('checked', false);
         } else if (checked === total) {
             $('#tree-selector input[type=checkbox]')[0].indeterminate = false;
             $('#tree-selector input[type=checkbox]').prop('checked', true);
         } else {
             $('#tree-selector input[type=checkbox]').prop('checked', false);
             $('#tree-selector input[type=checkbox]')[0].indeterminate = true;
         }
     };
 
     NotebookList.prototype.add_link = function (model, item) {
         var path = model.path,
             name = model.name;
         var running = (model.type == 'notebook' && this.sessions[path] !== undefined);
         
         item.data('name', name);
         item.data('path', path);
         item.data('type', model.type);
         item.find(".item_name").text(name);
         var icon = NotebookList.icons[model.type];
         if (running) {
             icon = 'running_' + icon;
         }
         var uri_prefix = NotebookList.uri_prefixes[model.type];
         item.find(".item_icon").addClass(icon).addClass('icon-fixed-width');
         var link = item.find("a.item_link")
             .attr('href',
                 utils.url_join_encode(
                     this.base_url,
                     uri_prefix,
                     path
                 )
             );
 
         item.find(".item_buttons .running-indicator").css('visibility', running ? '' : 'hidden');
 
         // directory nav doesn't open new tabs
         // files, notebooks do
         if (model.type !== "directory") {
             link.attr('target','_blank');
         }
     };
 
 
     NotebookList.prototype.add_name_input = function (name, item, icon_type) {
         item.data('name', name);
         item.find(".item_icon").addClass(NotebookList.icons[icon_type]).addClass('icon-fixed-width');
         item.find(".item_name").empty().append(
             $('<input/>')
             .addClass("filename_input")
             .attr('value', name)
             .attr('size', '30')
             .attr('type', 'text')
             .keyup(function(event){
                 if(event.keyCode == 13){item.find('.upload_button').click();}
                 else if(event.keyCode == 27){item.remove();}
             })
         );
     };
 
 
     NotebookList.prototype.add_file_data = function (data, item) {
         item.data('filedata', data);
     };
 
 
     NotebookList.prototype.shutdown_selected = function() {
         var that = this;
         this.selected.forEach(function(item) {
             if (item.type == 'notebook') {
                 that.shutdown_notebook(item.path);
             }
         });
     };
 
     NotebookList.prototype.shutdown_notebook = function(path) {
         var that = this;
         var settings = {
             processData : false,
             cache : false,
             type : "DELETE",
             dataType : "json",
             success : function () {
                 that.load_sessions();
             },
             error : utils.log_ajax_error,
         };
 
         var session = this.sessions[path];
         if (session) {
             var url = utils.url_join_encode(
                 this.base_url,
                 'api/sessions',
                 session
             );
             $.ajax(url, settings);
         }
     };
 
     NotebookList.prototype.rename_selected = function() {
         if (this.selected.length != 1) return;
 
         var that = this;
         var path = this.selected[0].path;
         var input = $('<input/>').attr('type','text').attr('size','25').addClass('form-control')
             .val(path);
         var dialog_body = $('<div/>').append(
             $("<p/>").addClass("rename-message")
                 .text('Enter a new directory name:')
         ).append(
             $("<br/>")
         ).append(input);
         var d = dialog.modal({
             title : "Rename directory",
             body : dialog_body,
             buttons : {
                 OK : {
                     class: "btn-primary",
                     click: function() {
                         that.contents.rename(path, input.val()).then(function() {
                             that.load_list();
                         }).catch(function(e) { 
                             dialog.modal({
                                 title: "Rename Failed",
                                 body: $('<div/>')
                                     .text("An error occurred while renaming \"" + path + "\" to \"" + input.val() + "\".")
                                     .append($('<div/>')
                                         .addClass('alert alert-danger')
                                         .text(e.message || e)),
                                 buttons: {
                                     OK: {'class': 'btn-primary'}
                                 }
                             });
                         });
                     }
                 },
                 Cancel : {}
             },
             open : function () {
                 // Upon ENTER, click the OK button.
                 input.keydown(function (event) {
                     if (event.which === keyboard.keycodes.enter) {
                         d.find('.btn-primary').first().click();
                         return false;
                     }
                 });
                 input.focus().select();
             }
         });
     };
 
     NotebookList.prototype.delete_selected = function() {
         var message;
         if (this.selected.length == 1) {
             message = 'Are you sure you want to permanently delete: ' + this.selected[0].name + '?';
         } else {
             message = 'Are you sure you want to permanently delete the ' + this.selected.length + ' files/folders selected?';
         }
         var that = this;
         dialog.modal({
             title : "Delete",
             body : message,
             buttons : {
                 Delete : {
                     class: "btn-danger",
                     click: function() {
                         // Shutdown any/all selected notebooks before deleting 
                         // the files.
                         that.shutdown_selected();
 
                         // Delete selected.
                         that.selected.forEach(function(item) {
                             that.contents.delete(item.path).then(function() {
                                     that.notebook_deleted(item.path);
                             }).catch(function(e) { 
                                 dialog.modal({
                                     title: "Delete Failed",
                                     body: $('<div/>')
                                         .text("An error occurred while deleting \"" + item.path + "\".")
                                         .append($('<div/>')
                                             .addClass('alert alert-danger')
                                             .text(e.message || e)),
                                     buttons: {
                                         OK: {'class': 'btn-primary'}
                                     }
                                 });
                             });
                         });
                     }
                 },
                 Cancel : {}
             }
         });
     };
 
     NotebookList.prototype.duplicate_selected = function() {
         var message;
         if (this.selected.length == 1) {
             message = 'Are you sure you want to duplicate: ' + this.selected[0].name + '?';
         } else {
             message = 'Are you sure you want to duplicate the ' + this.selected.length + ' files selected?';
         }
         var that = this;
         dialog.modal({
             title : "Delete",
             body : message,
             buttons : {
                 Duplicate : {
                     class: "btn-primary",
                     click: function() {
                         that.selected.forEach(function(item) {
                             that.contents.copy(item.path, that.notebook_path).then(function () {
                                 that.load_list();
                             }).catch(function(e) { 
                                 dialog.modal({
                                     title: "Delete Failed",
                                     body: $('<div/>')
                                         .text("An error occurred while deleting \"" + item.path + "\".")
                                         .append($('<div/>')
                                             .addClass('alert alert-danger')
                                             .text(e.message || e)),
                                     buttons: {
                                         OK: {'class': 'btn-primary'}
                                     }
                                 });
                             });
                         });
                     }
                 },
                 Cancel : {}
             }
         });
     };
 
     NotebookList.prototype.notebook_deleted = function(path) {
         /**
          * Remove the deleted notebook.
          */
         var that = this;
         $( ":data(path)" ).each(function() {
             var element = $(this);
             if (element.data("path") === path) {
                 element.remove();
                 events.trigger('notebook_deleted.NotebookList');
                 that._selection_changed();
             }
         });
     };
 
 
     NotebookList.prototype.add_upload_button = function (item) {
         var that = this;
         var upload_button = $('<button/>').text("Upload")
             .addClass('btn btn-primary btn-xs upload_button')
             .click(function (e) {
                 var filename = item.find('.item_name > input').val();
                 var path = utils.url_path_join(that.notebook_path, filename);
                 var filedata = item.data('filedata');
                 var format = 'text';
                 if (filename.length === 0 || filename[0] === '.') {
                     dialog.modal({
                         title : 'Invalid file name',
                         body : "File names must be at least one character and not start with a dot",
                         buttons : {'OK' : { 'class' : 'btn-primary' }}
                     });
                     return false;
                 }
                 if (filedata instanceof ArrayBuffer) {
                     // base64-encode binary file data
                     var bytes = '';
                     var buf = new Uint8Array(filedata);
                     var nbytes = buf.byteLength;
                     for (var i=0; i<nbytes; i++) {
                         bytes += String.fromCharCode(buf[i]);
                     }
                     filedata = btoa(bytes);
                     format = 'base64';
                 }
                 var model = {};
 
                 var name_and_ext = utils.splitext(filename);
                 var file_ext = name_and_ext[1];
                 var content_type;
                 if (file_ext === '.ipynb') {
                     model.type = 'notebook';
                     model.format = 'json';
                     try {
                         model.content = JSON.parse(filedata);
                     } catch (e) {
                         dialog.modal({
                             title : 'Cannot upload invalid Notebook',
                             body : "The error was: " + e,
                             buttons : {'OK' : {
                                 'class' : 'btn-primary',
                                 click: function () {
                                     item.remove();
                                 }
                             }}
                         });
                         return false;
                     }
                     content_type = 'application/json';
                 } else {
                     model.type = 'file';
                     model.format = format;
                     model.content = filedata;
                     content_type = 'application/octet-stream';
                 }
                 filedata = item.data('filedata');
 
                 var on_success = function () {
                     item.removeClass('new-file');
                     that.add_link(model, item);
                     that.session_list.load_sessions();
                 };
                 
                 var exists = false;
                 $.each(that.element.find('.list_item:not(.new-file)'), function(k,v){
                     if ($(v).data('name') === filename) { exists = true; return false; }
                 });
                 
                 if (exists) {
                     dialog.modal({
                         title : "Replace file",
                         body : 'There is already a file named ' + filename + ', do you want to replace it?',
                         buttons : {
                             Overwrite : {
                                 class: "btn-danger",
                                 click: function () {
                                     that.contents.save(path, model).then(on_success);
                                 }
                             },
                             Cancel : {
                                 click: function() { item.remove(); }
                             }
                         }
                     });
                 } else {
                     that.contents.save(path, model).then(on_success);
                 }
                 
                 return false;
             });
         var cancel_button = $('<button/>').text("Cancel")
             .addClass("btn btn-default btn-xs")
             .click(function (e) {
                 item.remove();
                 return false;
             });
         item.find(".item_buttons").empty()
             .append(upload_button)
             .append(cancel_button);
     };
 
 
     // Backwards compatability.
     IPython.NotebookList = NotebookList;
 
     return {'NotebookList': NotebookList};
 });