topic Explanation of or Examples demonstrating interaction between updateParameters and updateMessages in Python Questions https://community.esri.com/t5/python-questions/explanation-of-or-examples-demonstrating/m-p/1992#M183 <HTML><HEAD></HEAD><BODY><P>I am creating a python Toolbox that has the user select&nbsp;a geodatabase, and uses a hard-coded list of&nbsp;tables and associated field names to set the Value List filters for&nbsp;four&nbsp;additional parameters&nbsp;using the unique values in each of the specified fields. &nbsp;</P><P></P><P>So, in the updateParameters code, I am checking for the presence of each table and associated field, and if they exist, setting the parameter's filter list to&nbsp;the unique values. &nbsp;If not, I am clearing the filter list (set to []), and disabling the parameter.&nbsp;</P><P></P><P>If the&nbsp;geodatabase does not contain the table/tables or field/fields needed to create the Value List filters, I would like to provide a custom error message to let the user know that the geodatabase is missing some of the necessary&nbsp;tables/fields. &nbsp; &nbsp;However, it appears I cannot use setErrorMessage in updateParameters because it does not show up in the user interface. &nbsp; &nbsp;And, in this case, because there will be internal errors (some missing values, because the parameter has been disabled), it looks like updateErrors does not get called. &nbsp; I'm not sure about this last statement, because I am a bit unclear about how these class methods interact with what ArcGIS is doing behind the scenes.</P><P></P><P>I have combed the ESRI docs for custom toolboxes, as well as other materials that I could find, but am still have challenges with the code due to not quite knowing how these things flow. &nbsp; &nbsp;Most of the code examples I've found are quite simple and/or do not use these methods, so I'm interested in finding other examples that might help clarify this issue.</P><P></P><P>As a related question, I am&nbsp;having some&nbsp;challenges with use of the "altered" versus "hasBeenValidated" parameter. &nbsp; Some additional examples of comparing usage of these parameters would be helpful. &nbsp;</P></BODY></HTML> Thu, 27 Jul 2017 20:01:15 GMT AllisonBailey 2017-07-27T20:01:15Z Explanation of or Examples demonstrating interaction between updateParameters and updateMessages https://community.esri.com/t5/python-questions/explanation-of-or-examples-demonstrating/m-p/1992#M183 <HTML><HEAD></HEAD><BODY><P>I am creating a python Toolbox that has the user select&nbsp;a geodatabase, and uses a hard-coded list of&nbsp;tables and associated field names to set the Value List filters for&nbsp;four&nbsp;additional parameters&nbsp;using the unique values in each of the specified fields. &nbsp;</P><P></P><P>So, in the updateParameters code, I am checking for the presence of each table and associated field, and if they exist, setting the parameter's filter list to&nbsp;the unique values. &nbsp;If not, I am clearing the filter list (set to []), and disabling the parameter.&nbsp;</P><P></P><P>If the&nbsp;geodatabase does not contain the table/tables or field/fields needed to create the Value List filters, I would like to provide a custom error message to let the user know that the geodatabase is missing some of the necessary&nbsp;tables/fields. &nbsp; &nbsp;However, it appears I cannot use setErrorMessage in updateParameters because it does not show up in the user interface. &nbsp; &nbsp;And, in this case, because there will be internal errors (some missing values, because the parameter has been disabled), it looks like updateErrors does not get called. &nbsp; I'm not sure about this last statement, because I am a bit unclear about how these class methods interact with what ArcGIS is doing behind the scenes.</P><P></P><P>I have combed the ESRI docs for custom toolboxes, as well as other materials that I could find, but am still have challenges with the code due to not quite knowing how these things flow. &nbsp; &nbsp;Most of the code examples I've found are quite simple and/or do not use these methods, so I'm interested in finding other examples that might help clarify this issue.</P><P></P><P>As a related question, I am&nbsp;having some&nbsp;challenges with use of the "altered" versus "hasBeenValidated" parameter. &nbsp; Some additional examples of comparing usage of these parameters would be helpful. &nbsp;</P></BODY></HTML> Thu, 27 Jul 2017 20:01:15 GMT https://community.esri.com/t5/python-questions/explanation-of-or-examples-demonstrating/m-p/1992#M183 AllisonBailey 2017-07-27T20:01:15Z