Setting up a Paging Grid Selection Component to display selected text in a text field on an interface

Question

Hi All, 
 I am trying to configure a Paging Grid Selection Component (see definition code below). The grid will show a number of CDTs - comments coming from different approvers in a long running process. However, when a user clicks on a row in the grid, I would like the text in the "comment" field of the selected row to be displayed in an a!paragraphField interface control that is placed outside the grid control on the interface. Does anyone have guidance as to how I may go about this? 
 Thanks in advance. 
 --- 
 local!commentsQuery: a!queryEntity( entity: cons!CSHV_COMMENT_CDT, query: a!query( selection: a!querySelection(columns: { a!queryColumn(field: "author"), a!queryColumn(field: "timeStamp"), a!queryColumn(field: "status"), a!queryColumn(field: "comment"), }), filter: a!queryFilter( field: "cashAdvanceId.id", operator: "=", value: ri!CashAdvanceData.id ), PagingInfo: local!commentsPagingInfo ) ), 
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Hema · Accepted Answer

Hi Susan, 
 Please find the below code snippet, 
 load(
 local!input: {
 {
 id: 1,
 author: "Jack",
 status: "In Progress",
 comment: "Level 1 Approved"
 },
 {
 id: 2,
 author: "James",
 status: "Completed",
 comment: "All documents are verified"
 },
 {
 id: 3,
 author: "Lily",
 status: "Rejected",
 comment: "Level 1 Approved"
 }
 },
 /* Use query entity to get data to local!input*/
 local!pagingInfo: a!gridSelection(
 pagingInfo: a!pagingInfo(
 1,
 - 1
 )
 ),
 a!formLayout(
 contents: {
 a!gridField(
 totalCount: count(
 local!input
 ),
 columns: {
 a!gridTextColumn(
 label: "Author",
 field: "author",
 data: index(
 local!input,
 "author",
 null
 )
 ),
 a!gridTextColumn(
 label: "Status",
 field: "status",
 data: index(
 local!input,
 "status",
 null
 )
 ),
 a!gridTextColumn(
 label: "Comment",
 field: "comment",
 data: index(
 local!input,
 "comment",
 null
 )
 )
 },
 value: local!pagingInfo,
 saveInto: local!pagingInfo,
 identifiers: local!input.id,
 selection: true,
 validations: if(
 count(
 local!pagingInfo.selected
 ) > 1,
 "Only one row can be selected",
 {}
 )
 ),
 a!paragraphField(
 label: "Comment",
 readOnly: true,
 value: index(
 local!input.comment,
 wherecontains(
 local!pagingInfo.selected,
 local!input.id
 ),
 null
 ),
 showWhen: and(
 not(
 rule!APN_isBlank(
 local!pagingInfo.selected
 )
 ),
 count(
 local!pagingInfo.selected
 ) = 1
 )
 )
 }
 )
) 
 Few Suggestions, 
 
 In the query entity selection, include the primary key of the table. This will act as an identifier. In the above code, id is used as an identifier. 
 As selection should be enabled for the grid, for paging info a!pagingInfo() shouldn't be used. Instead, a!gridSelection() works. Please find this for reference . 
 The attribute 'validations' of a!gridField() can be used to restrict the number of selections. In the above code, I have restricted the number of selections to 1. 
 The attribute 'showWhen' of a!paragraphField() can be used to show or hide the paragraph field based on certain criteria. In the above code, I have hidden the Paragraph Field when no row is selected and when more than one row is selected. 
 
 Also, please find below the links to sail recipes for more info about paging grid. 
 https://docs.appian.com/suite/help/18.2/recipe_select_rows_in_a_grid.html 
 https://docs.appian.com/suite/help/18.2/recipe_limit_the_number_of_rows_in_a_grid_that_can_be_selected.html 
 https://docs.appian.com/suite/help/18.2/recipe_delete_rows_in_a_grid.html 
 
 Hope this helps!!! 
 
 Thanks, 
 Hema

Hema · Answer

Hi Susan, Please try the below code snippet, a!textField( label: "Selected Comment Row", readOnly: true, value: if( length( local!gridSelection.selected ) = 0, "No comment row selected", index( local!datasubset.data.comment, wherecontains( local!gridSelection.selected, local!datasubset.identifiers ) ) ) ) Thanks, Hema

charlesm492 · Answer

Try replacing the local!datasubset.data.comment with index(local!datasubset.data, "comment", null).

charlesm492 · Answer

No problem! Generally, if the data is ever expected to be null such as in this case where it's null before the user makes a selection, the index() function is safer to use than dot notation since it returns the third parameter in the case of an invalid index.

Chanakya Volam · Answer

Hi susana197 
 
1. Since you are querying the data from database set the Identifiers parameter of pagingGrid with primary key of your data 
2. In pagingGrid make sure to use a!gridselection in value and saveInto 
3. Once you do this when user selects a row the ID will be stored in a!gridselection.selected 
4. In the paragraph field use index(CDT,wherecontains(selectedID,CDT.ID)) 
 
Hope this helps you