Set value to edit grid in Extjs

I have one edit grid panel where i have all the records.开发者_开发技巧 I took 2 textfields on the same form. I want to set quantity value directly to the record whose id will match to the textfield value.

Any suggestion.

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This should more or less work.

var i = someTxtField.value();
editGrid.getStore().data.items[i]['somevalue'] = "fooBar";
editGrid.doLayout();