there is a url which show us how can DD from a grid to anthor:
http://www.extjs.com/deploy/dev/exam...d_to_grid.html


I set firstGrid a selectModel:
sm = new Ext.grid.CheckboxSelectionModel({singleSelect:false});

but when the code:"enableDragDrop : true,"
firstGrid can checked only one record.

only in the case that I pressed Ctrl or Shift

this is not a good idea I thought



Code:
Ext.onReady(function(){

    var myData = {
		records : [
			{ name : "Rec 0", column1 : "0", column2 : "0" },
			{ name : "Rec 1", column1 : "1", column2 : "1" },
			{ name : "Rec 2", column1 : "2", column2 : "2" },
			{ name : "Rec 3", column1 : "3", column2 : "3" },
			{ name : "Rec 4", column1 : "4", column2 : "4" },
			{ name : "Rec 5", column1 : "5", column2 : "5" },
			{ name : "Rec 6", column1 : "6", column2 : "6" },
			{ name : "Rec 7", column1 : "7", column2 : "7" },
			{ name : "Rec 8", column1 : "8", column2 : "8" },
			{ name : "Rec 9", column1 : "9", column2 : "9" }
		]
	};

    var firstGridStore = new Ext.data.JsonStore({
        fields : [
			{name: 'name', mapping : 'name'},
			{name: 'column1', mapping : 'column1'},
			{name: 'column2', mapping : 'column2'}
		],
		data   : myData,
		root   : 'records'
    });

    //	singleSelect:false
	var sm = new Ext.grid.CheckboxSelectionModel({singleSelect:false});

	/**
	 * grid
	 */
    var firstGrid = new Ext.grid.GridPanel({
    	//	select more
    	sm				 : sm,
		ddGroup          : 'secondGridDDGroup',
        store            : firstGridStore,
        columns          : [
			sm,
			{ id : 'name', header: "Record Name", width: 160, sortable: true, dataIndex: 'name'},
			{header: "column1", width: 50, sortable: true, dataIndex: 'column1'},
			{header: "column2", width: 50, sortable: true, dataIndex: 'column2'}
		],
		enableDragDrop   : true,	//	why couldn't select more ?
		primaryButtonOnly: true,
        stripeRows       : true,
        autoExpandColumn : 'name',
        title            : 'First Grid'
    });

    var secondGridStore = new Ext.data.JsonStore({
        fields : [
			{name: 'name', mapping : 'name'},
			{name: 'column1', mapping : 'column1'},
			{name: 'column2', mapping : 'column2'}
		],
		root   : 'records'
    });

    var secondGrid = new Ext.grid.GridPanel({
		ddGroup          : 'firstGridDDGroup',
        store            : secondGridStore,
        columns          : [
			{ id : 'name', header: "Record Name", width: 160, sortable: true, dataIndex: 'name'},
			{header: "column1", width: 50, sortable: true, dataIndex: 'column1'},
			{header: "column2", width: 50, sortable: true, dataIndex: 'column2'}
		],
		enableDragDrop   : true,
        stripeRows       : true,
        autoExpandColumn : 'name',
        title            : 'Second Grid'
    });

	var displayPanel = new Ext.Panel({
		width        : 650,
		height       : 300,
		layout       : 'hbox',
		renderTo     : document.body,
		defaults     : { flex : 1 }, //auto stretch
		layoutConfig : { align : 'stretch' },
		items        : [
			firstGrid,
			secondGrid
		],
		bbar    : [
			'->', // Fill
			{
				text    : 'Reset both grids',
				handler : function() {
					//refresh source grid
					firstGridStore.loadData(myData);

					//purge destination grid
					secondGridStore.removeAll();
				}
			}
		]
	});

    var firstGridDropTargetEl =  firstGrid.getView().scroller.dom;
    new Ext.dd.DropTarget(firstGridDropTargetEl, {
            ddGroup    : 'firstGridDDGroup',
            notifyDrop : function(ddSource, e, data){
                    var records =  ddSource.dragData.selections;
                    Ext.each(records, ddSource.grid.store.remove, ddSource.grid.store);
                    firstGrid.store.add(records);
                    firstGrid.store.sort('name', 'ASC');
                    return true
            }
    });

	var secondGridDropTargetEl = secondGrid.getView().scroller.dom;
    new Ext.dd.DropTarget(secondGridDropTargetEl, {
            ddGroup    : 'secondGridDDGroup',
            notifyDrop : function(ddSource, e, data){
                    var records =  ddSource.dragData.selections;
                    Ext.each(records, ddSource.grid.store.remove, ddSource.grid.store);
                    secondGrid.store.add(records);
                    secondGrid.store.sort('name', 'ASC');
                    return true
            }
    });
});