    /**
     * The Ext.grid.plugin.RowEditing plugin injects editing at a row level for a Grid. When editing begins,
     * a small floating dialog will be shown for the appropriate row. Each editable column will show a field
     * for editing. There is a button to save or cancel all changes for the edit.
     *
     * The field that will be used for the editor is defined at the
     * {@link Ext.grid.column.Column#editor editor}. The editor can be a field instance or a field configuration.
     * If an editor is not specified for a particular column then that column won't be editable and the value of
     * the column will be displayed. To provide a custom renderer for non-editable values, use the
     * {@link Ext.grid.column.Column#editRenderer editRenderer} configuration on the column.
     *
     * The editor may be shared for each column in the grid, or a different one may be specified for each column.
     * An appropriate field type should be chosen to match the data structure that it will be editing. For example,
     * to edit a date, it would be useful to specify {@link Ext.form.field.Date} as the editor.
     *
     *     @example
     *     Ext.create('Ext.data.Store', {
     *         storeId:'simpsonsStore',
     *         fields:['name', 'email', 'phone'],
     *         data: [
     *             {"name":"Lisa", "email":"lisa@simpsons.com", "phone":"555-111-1224"},
     *             {"name":"Bart", "email":"bart@simpsons.com", "phone":"555-222-1234"},
     *             {"name":"Homer", "email":"home@simpsons.com", "phone":"555-222-1244"},
     *             {"name":"Marge", "email":"marge@simpsons.com", "phone":"555-222-1254"}
     *         ]
     *     });
     *
     *     Ext.create('Ext.grid.Panel', {
     *         title: 'Simpsons',
     *         store: Ext.data.StoreManager.lookup('simpsonsStore'),
     *         columns: [
     *             {header: 'Name',  dataIndex: 'name', editor: 'textfield'},
     *             {header: 'Email', dataIndex: 'email', flex:1,
     *                 editor: {
     *                     xtype: 'textfield',
     *                     allowBlank: false
     *                 }
     *             },
     *             {header: 'Phone', dataIndex: 'phone'}
     *         ],
     *         selType: 'rowmodel',
     *         plugins: [
     *             Ext.create('Ext.grid.plugin.RowEditing', {
     *                 clicksToEdit: 1
     *             })
     *         ],
     *         height: 200,
     *         width: 400,
     *         renderTo: Ext.getBody()
     *     });
     */
    Ext.define('Ext.grid.plugin.RowEditing', {
        extend: 'Ext.grid.plugin.Editing',
        alias: 'plugin.rowediting',

        requires: [
            'Ext.grid.RowEditor'
        ],

        editStyle: 'row',

        /**
         * @cfg {Boolean} autoCancel
         * True to automatically cancel any pending changes when the row editor begins editing a new row.
         * False to force the user to explicitly cancel the pending changes. Defaults to true.
         */
        autoCancel: true,

        /**
         * @cfg {Number} clicksToMoveEditor
         * The number of clicks to move the row editor to a new row while it is visible and actively editing another row.
         * This will default to the same value as {@link Ext.grid.plugin.Editing#clicksToEdit clicksToEdit}.
         */

        /**
         * @cfg {Boolean} errorSummary
         * True to show a {@link Ext.tip.ToolTip tooltip} that summarizes all validation errors present
         * in the row editor. Set to false to prevent the tooltip from showing. Defaults to true.
         */
        errorSummary: true,

        constructor: function() {
            var me = this;

            me.callParent(arguments);

            if (!me.clicksToMoveEditor) {
                me.clicksToMoveEditor = me.clicksToEdit;
            }

            me.autoCancel = !!me.autoCancel;
        },

        init: function(grid) {
            this.callParent([grid]);
        },

        /**
         * @private
         * AbstractComponent calls destroy on all its plugins at destroy time.
         */
        destroy: function() {
            var me = this;
            Ext.destroy(me.editor);
            me.callParent(arguments);
        },

        /**
         * Starts editing the specified record, using the specified Column definition to define which field is being edited.
         * @param {Ext.data.Model} record The Store data record which backs the row to be edited.
         * @param {Ext.data.Model} columnHeader The Column object defining the column to be edited.
         * @return `true` if editing was started, `false` otherwise.
         */
        startEdit: function(record, columnHeader) {
            var me = this,
                editor = me.getEditor();

            if ((me.callParent(arguments) !== false) && (editor.beforeEdit() !== false)) {
                editor.startEdit(me.context.record, me.context.column);
                return true;
            }
            return false;
        },

        // private
        cancelEdit: function() {
            var me = this;

            if (me.editing) {
                me.getEditor().cancelEdit();
                me.callParent(arguments);
            }
        },

        // private
        completeEdit: function() {
            var me = this;

            if (me.editing && me.validateEdit()) {
                me.editing = false;
                me.fireEvent('edit', me, me.context);
            }
        },

        // private
        validateEdit: function() {
            var me             = this,
                editor         = me.editor,
                context        = me.context,
                record         = context.record,
                newValues      = {},
                originalValues = {},
                editors        = editor.items.items,
                e,
                eLen           = editors.length,
                name, item;

            for (e = 0; e < eLen; e++) {
                item = editors[e];
                name = item.name;

                newValues[name]      = item.getValue();
                originalValues[name] = record.get(name);
            }

            Ext.apply(context, {
                newValues      : newValues,
                originalValues : originalValues
            });

            return me.callParent(arguments) && me.getEditor().completeEdit();
        },

        // private
        getEditor: function() {
            var me = this;

            if (!me.editor) {
                me.editor = me.initEditor();
            }
            return me.editor;
        },

        // private
        initEditor: function() {
            var me       = this,
                grid     = me.grid,
                view     = me.view,
                headerCt = grid.headerCt,
                btns     = ['saveBtnText', 'cancelBtnText', 'errorsText', 'dirtyText'],
                b,
                bLen     = btns.length,
                cfg      = {
                    autoCancel: me.autoCancel,
                    errorSummary: me.errorSummary,
                    fields: headerCt.getGridColumns(),
                    hidden: true,

                    // keep a reference..
                    editingPlugin: me,
                    renderTo: view.el
                },
                item;

            for (b = 0; b < bLen; b++) {
                item = btns[b];

                if (Ext.isDefined(me[item])) {
                    cfg[item] = me[item];
                }
            }

            return Ext.create('Ext.grid.RowEditor', cfg);
        },

        // private
        initEditTriggers: function() {
            var me = this,
                moveEditorEvent = me.clicksToMoveEditor === 1 ? 'click' : 'dblclick';

            me.callParent(arguments);

            if (me.clicksToMoveEditor !== me.clicksToEdit) {
                me.mon(me.view, 'cell' + moveEditorEvent, me.moveEditorByClick, me);
            }
        },

        addHeaderEvents: function(){
            var me = this;
            me.callParent();

            me.mon(me.grid.headerCt, {
                scope: me,
                columnresize: me.onColumnResize,
                columnhide: me.onColumnHide,
                columnshow: me.onColumnShow,
                columnmove: me.onColumnMove
            });
        },

        startEditByClick: function() {
            var me = this;
            if (!me.editing || me.clicksToMoveEditor === me.clicksToEdit) {
                me.callParent(arguments);
            }
        },

        moveEditorByClick: function() {
            var me = this;
            if (me.editing) {
                me.superclass.onCellClick.apply(me, arguments);
            }
        },

        // private
        onColumnAdd: function(ct, column) {
            if (column.isHeader) {
                var me = this,
                    editor;

                me.initFieldAccessors(column);

                // Only inform the editor about a new column if the editor has already been instantiated,
                // so do not use getEditor which instantiates the editor if not present.
                editor = me.editor;
                if (editor && editor.onColumnAdd) {
                    editor.onColumnAdd(column);
                }
            }
        },

        // private
        onColumnRemove: function(ct, column) {
            if (column.isHeader) {
                var me = this,
                    editor = me.getEditor();

                if (editor && editor.onColumnRemove) {
                    editor.onColumnRemove(column);
                }
                me.removeFieldAccessors(column);
            }
        },

        // private
        onColumnResize: function(ct, column, width) {
            if (column.isHeader) {
                var me = this,
                    editor = me.getEditor();

                if (editor && editor.onColumnResize) {
                    editor.onColumnResize(column, width);
                }
            }
        },

        // private
        onColumnHide: function(ct, column) {
            // no isHeader check here since its already a columnhide event.
            var me = this,
                editor = me.getEditor();

            if (editor && editor.onColumnHide) {
                editor.onColumnHide(column);
            }
        },

        // private
        onColumnShow: function(ct, column) {
            // no isHeader check here since its already a columnshow event.
            var me = this,
                editor = me.getEditor();

            if (editor && editor.onColumnShow) {
                editor.onColumnShow(column);
            }
        },

        // private
        onColumnMove: function(ct, column, fromIdx, toIdx) {
            // no isHeader check here since its already a columnmove event.
            var me = this,
                editor = me.getEditor();

            if (editor && editor.onColumnMove) {
                editor.onColumnMove(column, fromIdx, toIdx);
            }
        },

        // private
        setColumnField: function(column, field) {
            var me = this,
                editor = me.getEditor();

            editor.removeField(column);
            me.callParent(arguments);
            me.getEditor().setField(column);
        }
    });