Very unfortunately ExtJS doesn’t offer a validator for its checkbox component. Normally a validator checks whether a field is valid and takes care of displaying an error message if not. For a checkbox we would like that to happen if the checkbox is not selected. Overriding the validate function of the checkbox we can provide such a functionality for all checkbox instances we are about to create: Ext.form.Checkbox.prototype.validate = function(){ if (this....
When you are doing client/server communication with ExtJS you probably run into the problem that you want to handle server side errors in a generic way. A solution that I found is to override the handleFailure function in the Ext.data.Connection class: Ext.data.Connection.prototype._handleFailure = Ext.data.Connection.prototype.handleFailure; Ext.data.Connection.prototype.handleFailure = function(response, e) { var errorText = Ext.DomQuery.selectValue("Reason/Text", response.responseXML, "Unknown Error"); Ext.Msg.alert('Error', errorText); Ext.data.Connection.prototype._handleFailure.call(this, response, e); }; This handler simply is called whenever a server side failure occurs....