Dependencies

When working with custom lists it is often useful if the values that are shown in one list (the child list) are dependent on the value selected from another list (the parent list). An example of two lists that are related like this would be a Country list and a City list.

PPO provides this functionality to allow a dependency to be established between any two custom lists which indicate how the items in the two lists are related.

To set up a dependency, hover over the Administration Menu and then click on the Dependencies menu item from the drop down list. 

From the Dependency List page click on the Add button and follow these steps:

1. Provide a description for the dependency. The description should be descriptive enough to differentiate the dependency from other dependencies, e.g. Country & City. 

2. Select the Parent and Child custom lists, respectively. The Child custom list (in this example, Project - City) will be the one dependent on the item selected in the Parent custom list (Project - Country).

3. Select a custom list item from the Parent Values list (only parent custom list items will be available from this list). All the values from the child custom list will show below. Select the applicable child values for the parent value.

Continue this process by selecting a new parent value and selecting the new child values, until you have identified child values for each parent value.

The child values can be filtered to see only linked, unlinked or all items by clicking on the applicable option in the Child Items to Show field.

After all the child values have been selected, click on the Submit button.

 

Note that when child values are added to the custom list, the dependency will also need to be updated. If child values were added and the dependency was not updated, the unlinked child values will appear under the Unlinked heading.

The last step in setting up your dependency is to link the dependency to the applicable data field. To do this, access the Data Field Edit page of the child data field (if you are mapping countries to cities, the city will be the child data field).

You will notice that the Dependency field on this page is now expanded and the newly created dependency is available from the list. Select the dependency name, and then select the dependency parent custom list from the Dependency Parent Field drop-down list. Then click on the Submit button.

If you now access the applicable entity and edit or add a record, you will notice that the parent value will first have to be selected, before the child custom list is populated with the pre-defined values.

Deleting a dependency

Dependencies can only be deleted if they are not linked to a data field. If you try and delete the dependency that is currently used, the following error message will be displayed: 

If the dependency needs to be deleted, ensure you unlink it from the child data field, and then access the dependency again and click on the Delete button.