From 313e58519cba5485dd8f3f3f6ccc41fcb366a172 Mon Sep 17 00:00:00 2001
From: Damyon Wiese <damyon@moodle.com>
Date: Fri, 2 Aug 2013 16:34:24 +0800
Subject: [PATCH] MDL-36002 dragdrop: focus fix and exception catching

This sets the focus correctly after a cancel or drop event.
It also catches exceptions from the lock/unlock functions.
---
 lib/yui/dragdrop/dragdrop.js | 23 +++++++++++++++++------
 1 file changed, 17 insertions(+), 6 deletions(-)

diff --git a/lib/yui/dragdrop/dragdrop.js b/lib/yui/dragdrop/dragdrop.js
index 4e9e7d18fd9..3fdec8e20cf 100644
--- a/lib/yui/dragdrop/dragdrop.js
+++ b/lib/yui/dragdrop/dragdrop.js
@@ -66,12 +66,20 @@ YUI.add('moodle-core-dragdrop', function(Y) {
 
         lock_drag_handle: function(drag, classname) {
             // Disable dragging
-            drag.removeHandle('.'+classname);
+            try {
+                drag.removeHandle('.'+classname);
+            } catch (e) {
+                // Throws exceptions if the drag is not started with the mouse.
+            }
         },
 
         unlock_drag_handle: function(drag, classname) {
             // Enable dragging
-            drag.addHandle('.'+classname);
+            try {
+                drag.addHandle('.'+classname);
+            } catch (e) {
+                // Throws exceptions if the drag is not started with the mouse.
+            }
         },
 
         ajax_failure: function(response) {
@@ -234,9 +242,11 @@ YUI.add('moodle-core-dragdrop', function(Y) {
          * @method global_start_keyboard_drag
          * @param {Event} e The keydown / click event on the grab handle.
          * @param {Node} dragcontainer The resolved draggable node (an ancestor of the drag handle).
+         * @param {Node} draghandle The node that triggered this action.
          */
-        global_start_keyboard_drag : function(e, dragcontainer) {
+        global_start_keyboard_drag : function(e, draghandle, dragcontainer) {
             M.core.dragdrop.keydragcontainer = dragcontainer;
+            M.core.dragdrop.keydraghandle = draghandle;
 
             // Indicate to a screenreader the node that is selected for drag and drop.
             dragcontainer.setAttribute('aria-grabbed', 'true');
@@ -341,7 +351,8 @@ YUI.add('moodle-core-dragdrop', function(Y) {
             });
 
             this.global_drop_over(e);
-            dragcontainer.focus();
+            this.global_drop_hit(e);
+            M.core.dragdrop.keydraghandle.focus();
         },
 
         /**
@@ -352,7 +363,7 @@ YUI.add('moodle-core-dragdrop', function(Y) {
         global_cancel_keyboard_drag : function() {
             if (M.core.dragdrop.keydragcontainer) {
                 M.core.dragdrop.keydragcontainer.setAttribute('aria-grabbed', 'false');
-                M.core.dragdrop.keydragcontainer.focus();
+                M.core.dragdrop.keydraghandle.focus();
                 M.core.dragdrop.keydragcontainer = null;
             }
         },
@@ -403,7 +414,7 @@ YUI.add('moodle-core-dragdrop', function(Y) {
 
             // Valid event - start the keyboard drag.
             dragcontainer = draghandle.ancestor('.yui3-dd-drop');
-            this.global_start_keyboard_drag(e, dragcontainer);
+            this.global_start_keyboard_drag(e, draghandle, dragcontainer);
 
             e.preventDefault();
         },
-- 
2.43.0