Help, I can not get passed this error: 'this.getSelectionModel is not a function' in firebug. I'm trying to implement a variation of "grid with data writer" from the extjs4 examples: My variation is I have a checkcolumn with an editor that when, the checkbox is unchecked, the proxy runs a store operation. The problem is I don't think the selection model is getting loaded right, because when the browser load gets to this line: "this.getSelectionModel().on('selectionchange', this.onSelectChange, this);", it blows up. If I take that line out, the page will load, but when I run onDeleteClick(), I get a firebug error that says this.getView() is undefined.