Merge pull request #8281 from minrk/finish-8067

finish scroll-cell PR

IPython/html/static/notebook/js/actions.js

@@ -368,6 +368,26 b' define(function(require){'
                 return env.notebook.scroll_manager.scroll(-1);
             },
         },
+        'scroll-cell-center': {
+            help: "Scroll the current cell to the center",
+            handler: function (env, event) {
+                if(event){
+                    event.preventDefault();
+                }
+                var cell = env.notebook.get_selected_index();
+                return env.notebook.scroll_cell_percent(cell, 50, 0);
+            }
+        },
+        'scroll-cell-top': {
+            help: "Scroll the current cell to the top",
+            handler: function (env, event) {
+                if(event){
+                    event.preventDefault();
+                }
+                var cell = env.notebook.get_selected_index();
+                return env.notebook.scroll_cell_percent(cell, 0, 0);
+            }
+        },
         'save-notebook':{
             help: "Save and Checkpoint",
             help_index : 'fb',

IPython/html/static/notebook/js/keyboardmanager.js

@@ -79,7 +79,7 b' define(['
             'up'                  : 'ipython.move-cursor-up-or-previous-cell',
             'down'                : 'ipython.move-cursor-down-or-next-cell',
             'ctrl-shift--'        : 'ipython.split-cell-at-cursor',
-            'ctrl-shift-subtract' : 'ipython.split-cell-at-cursor'
+            'ctrl-shift-subtract' : 'ipython.split-cell-at-cursor',
         };
     };
 

IPython/html/static/notebook/js/notebook.js

@@ -351,11 +351,30 b' define(function (require) {'
      * @return {integer} Pixel offset from the top of the container
      */
     Notebook.prototype.scroll_to_cell = function (index, time) {
+        return this.scroll_cell_percent(index, 0, time);
+    };
+
+    /**
+     * Scroll the middle of the page to a given cell.
+     *
+     * @param {integer}  index - An index of the cell to view
+     * @param {integer}  percent - 0-100, the location on the screen to scroll.
+     *                   0 is the top, 100 is the bottom.
+     * @param {integer}  time - Animation time in milliseconds
+     * @return {integer} Pixel offset from the top of the container
+     */
+    Notebook.prototype.scroll_cell_percent = function (index, percent, time) {
         var cells = this.get_cells();
         time = time || 0;
+        percent = percent || 0;
         index = Math.min(cells.length-1,index);
         index = Math.max(0             ,index);
-        var scroll_value = cells[index].element.position().top-cells[0].element.position().top ;
+        var sme = this.scroll_manager.element;
+        var h = sme.height();
+        var st = sme.scrollTop();
+        var t = sme.offset().top;
+        var ct = cells[index].element.offset().top;
+        var scroll_value =  st + ct - (t + .01 * percent * h);
         this.scroll_manager.element.animate({scrollTop:scroll_value}, time);
         return scroll_value;
     };