Grids are provided with their data from a data source. Some types of data source allow the administrator to set a root from where the data source "works out" takes its' data. In such cases the administrator first sets up the datasource and form - in Object Modeller. Then they will configure the Form, when they add it to the web page, so that its data source will start from the correct object, when calculating its data.
The attached video shows a form being configured for a ParentObject, set to a selected Book - and leading to the people who are "interested in" it.
Furthermore, the value of the parent object is shown when we switch it to a different book as the parent object.
In the Data source Help File we have explained the various Datasource types, including the simple "Association" type. In that example we used a "Book" to "Contact" by the relationship "is interested in" , to provide a datasource, using the "Parent Object" as the root for its data.
The Help video attached to this Help resource shows how this has exposed the contacts who were interested in a book - Lord of the Rings.
This is a fairly basic means of obtaining data from the object structure. To further demonstrate the power that this method gives you, we have added in a second Book and some more contacts. Some of these contacts are only interested in the new book, others are interested in this book and the Lord of the Rings. And some of the contacts interested in the Lord of the Rings are also intereted in the new book;
We have then retruned to the website and re-configured the Front end form to be focussed on the new book - Olsens Book of British Birds. Consequently the form displays all contacts interested in this book.
Of course there could be hunderds of different Books and thousands of Contacts, all with multiple interests in books. The Form will always return those contacts that fit the datasource.
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