Reveal cursor on panel expand

src/editor/Editor.js

@@ -986,8 +986,13 @@ define(function (require, exports, module) {
      * Set the editor size in pixels or percentage
      * @param {(number|string)} width
      * @param {(number|string)} height
+     * @param {boolean=} revealCursor whether or not to reveal the cursor after resize
      */
-    Editor.prototype.setSize = function (width, height) {
+    Editor.prototype.setSize = function (width, height, revealCursor) {
+        if (revealCursor) {
+            var delta = height - $(this.getScrollerElement()).height();
+            this.showCursorAfterResize(delta);
+        }
         this._codeMirror.setSize(width, height);
     };
 
@@ -1030,6 +1035,26 @@ define(function (require, exports, module) {
             this.setScrollPos(null, pos);
         }
     };
+
+    /**
+     * Determines if the cursor will be hidden, and if it will scrolls the
+     * editor viewport restoring the distance between the cursor and the bottom
+     * of the editor prior to editor resize, or centering the cursor vertically
+     * in the editor if that requires less scrolling.
+     *
+     * @param {number} delta The change in editor height
+     */
+    Editor.prototype.showCursorAfterResize = function (delta) {
+        var $scrollerElement = $(this.getScrollerElement()),
+            editorHeight = $scrollerElement.height(),
+            cursorToTop = this._codeMirror.cursorCoords(null, "page").bottom - $scrollerElement.offset().top,
+            cursorToBottom = editorHeight - cursorToTop;
+
+        if (delta < 0 && -delta > cursorToBottom) {
+            var scrollTarget = this.getScrollPos().y + Math.min(cursorToTop - (editorHeight + delta) / 2, -delta);
+            this.setScrollPos(null, scrollTarget);
+        }
+    };
 
     /**
      * Given a position, returns its index within the text (assuming \n newlines)

src/editor/EditorManager.js

@@ -501,29 +501,32 @@ define(function (require, exports, module) {
      * some other cases are handled by external code calling `resizeEditor()` (e.g. ModalBar hide/show).
      * 
      * @param {number} editorAreaHt
-     * @param {string=} refreshFlag For internal use. Set to "force" to ensure the editor will refresh, 
-     *    "skip" to ensure the editor does not refresh, or leave undefined to let `_onEditorAreaResize()`
-     *    determine whether it needs to refresh.
+     * @param {{refresh:string=, revealCursor:boolean=}} options For internal use.
+     *    Set to "force" to ensure the editor will refresh, "skip" to ensure the editor does not refresh, or
+     *    leave undefined to let `_onEditorAreaResize()` determine whether it needs to refresh.
+     *    Set revealCursor to true to reveal cursor.
      */
-    function _onEditorAreaResize(event, editorAreaHt, refreshFlag) {
+    function _onEditorAreaResize(event, editorAreaHt, options) {
         if (_currentEditor) {
             var curRoot = _currentEditor.getRootElement(),
-                curWidth = $(curRoot).width();
-            if (!curRoot.style.height || $(curRoot).height() !== editorAreaHt) {
+                curWidth = $(curRoot).width(),
+                curHeight = $(curRoot).height();
+
+            if (!curRoot.style.height || curHeight !== editorAreaHt) {
                 // Call setSize() instead of $.height() to allow CodeMirror to
                 // check for options like line wrapping
-                _currentEditor.setSize(null, editorAreaHt);
-                if (refreshFlag === undefined) {
-                    refreshFlag = REFRESH_FORCE;
+                _currentEditor.setSize(null, editorAreaHt, options.revealCursor);
+                if (options.refresh === undefined) {
+                    options.refresh = REFRESH_FORCE;
                 }
             } else if (curWidth !== _lastEditorWidth) {
-                if (refreshFlag === undefined) {
-                    refreshFlag = REFRESH_FORCE;
+                if (options.refresh === undefined) {
+                    options.refresh = REFRESH_FORCE;
                 }
             }
             _lastEditorWidth = curWidth;
 
-            if (refreshFlag === REFRESH_FORCE) {
+            if (options.refresh === REFRESH_FORCE) {
                 _currentEditor.refreshAll(true);
             }
         }

src/view/PanelManager.js

@@ -101,16 +101,16 @@ define(function (require, exports, module) {
      * Calculates a new size for editor-holder and resizes it accordingly, then and dispatches the "editorAreaResize"
      * event. (The editors within are resized by EditorManager, in response to that event).
      * 
-     * @param {string=} refreshHint  One of "skip", "force", or undefined. See EditorManager docs.
+     * @param {{refresh:string=, revealCursor:boolean=}} options See EditorManager._onEditorAreaResize docs.
      */
-    function triggerEditorResize(refreshHint) {
+    function triggerEditorResize(options) {
         // Find how much space is left for the editor
         var editorAreaHeight = calcEditorHeight();
 
         $editorHolder.height(editorAreaHeight);  // affects size of "not-editor" placeholder as well
 
         // Resize editor to fill the space
-        $(exports).trigger("editorAreaResize", [editorAreaHeight, refreshHint]);
+        $(exports).trigger("editorAreaResize", [editorAreaHeight, options || {}]);
     }
 
 
@@ -144,14 +144,18 @@ define(function (require, exports, module) {
 
     /** Trigger editor area resize whenever the given panel is shown/hidden/resized */
     function listenToResize($panel) {
-        // Update editor height when shown/hidden, & continuously as panel is resized
-        $panel.on("panelCollapsed panelExpanded panelResizeUpdate", function () {
+        // Update editor height when hidden, & continuously as panel is resized
+        $panel.on("panelCollapsed panelResizeUpdate", function () {
             triggerEditorResize();
         });
         // Update max size of sibling panels when shown/hidden, & at *end* of resize gesture
         $panel.on("panelCollapsed panelExpanded panelResizeEnd", function () {
             updateResizeLimits();
         });
+        // Update editor height when shown, & scroll to show cursor above panel if necessary
+        $panel.on("panelExpanded", function () {
+            triggerEditorResize({revealCursor: true});
+        });
     }