How to: Narrow a list with filter chips

Open a list that's already narrowed down for a purpose, such as „certificates that expire within 14 days“ reached by clicking a key figure on the start page, show the user why the list is shorter, and let them remove that condition with a single click.

Requires WKL Forms Object Library 1.45 or later.

• A filter chip is a named WHERE condition. WklGrid.AddFilterChip(Name, Caption, Condition) narrows down the records; the grid applies (Filter) AND (chip 1) AND (chip 2) ..., both in memory and in server mode.
• The filter bar shows it. Below the records, each chip appears as a „Caption ✕“ button. Clicking it, pressing Delete on it, or invoking it with a screen reader removes the chip, and the records are read again.
• The application is notified. FilterChipRemoved(Name, ByUser) reports every removal, so a heading or a key figure can follow along.
• The start page passes the reason. A WklKpiCard with a Key raises Click(Key); the shell shows the list page and adds the chip that belongs to that key.

In the module of the shell form frmShell (with the start page card kpiExpiring, Key = "expiring", and the page subform sfPage):

Option Compare Database
Option Explicit
 
Private Sub kpiExpiring_Click(ByVal Key As String)
    Me!sfPage.SourceObject = "frmCertificates"
    With Me!sfPage.Form!grdCertificates.Object
        .ClearFilterChips
        Select Case Key
            Case "expiring"
                .AddFilterChip "expiring", "expires within 14 days", "Expiry Between Date() And Date() + 14"
            Case "locked"
                .AddFilterChip "locked", "locked", "Status = 'Locked'"
        End Select
    End With
End Sub

In the module of the page form frmCertificates:

Private Sub grdCertificates_FilterChipRemoved(ByVal Name As String, ByVal ByUser As Boolean)
    If ByUser Then Me!lblHeading.Caption = "All certificates"
End Sub

• A chip with an existing name replaces that chip in place, and the bar keeps its order. RemoveFilterChip raises FilterChipRemoved with ByUser = False; ClearFilterChips doesn't raise anything.
• Filter remains the application's own condition and doesn't include the chips. A JPath filter ($...) can't be combined with chips and is rejected while chips are set.
• Chips require a RecordSource; a grid bound only to a Recordset (for example, on a UserForm) rejects them.
• Chips aren't saved with the form or in the remembered column arrangement, so set them each time the page is opened for a purpose.
• Clear filter in the bar removes the user's column filters, not the chips.
• ShowFilterBar = False hides the bar; the chips still apply, but the user can't remove them.

• How to: Build a start page with key figures
• How to: Handle your own shortcuts in an application shell
• How to: Filter grid columns
• API reference: WklGrid.AddFilterChip