Filter Dropdown Button

• Jul 29, 2021
• 2 minutes to read

Column headers in Table Views and Banded Table Views, card row captions in Card Views, and data items in Layout Views can display filter dropdown buttons (filter buttons for short). End-users can click these buttons to invoke filter dropdowns.

Feature	Related Members
Visibility	In Table and Banded Table Views, filter buttons are available only if the View’s OptionsCustomize.ColumnFiltering option is enabled. In this case, the filter button’s visibility for each column is specified using the column’s Options.Filtering or Options.FilteringPopup property. At the same time, if the View’s OptionsCustomize.ColumnFiltering option is disabled, filter buttons are not visible regardless of the column’s Options.Filtering or Options.FilteringPopup property. Card Views provide a similar option for specifying the filter buttons’ visibility. You should specify the buttons’ visibility at the View’s level using the OptionsCustomize.RowFiltering property. To disable filter buttons for a particular row, set the row’s Options.Filtering or Options.FilteringPopup property to False. Use the View’s OptionsView.ShowColumnFilterButtons (or OptionsView.ShowRowFilterButtons) property to specify whether filter buttons are always visible in all columns (rows), or only in a particular column (row), if an end-user hovers the mouse pointer over this column (row). Note that filter buttons are not displayed for columns and rows that use editors which do not support filtering operations. For instance, filter buttons will not be displayed for columns and rows that use BLOB editors.
Appearance	Basically, the filter buttons’ look and feel is specified by the grid control’s LookAndFeel property settings. You can also provide manual button painting by handling the following events: The View’s OnCustomDrawColumnHeader or a column’s OnCustomDrawHeader event if using a Table View or a Banded Table View. The View’s OnCustomDrawCell or a row’s OnCustomDrawCell event if using a Card View. In tabular Views, you can switch the display mode for filter buttons via the View’s OptionsView.HeaderFilterButtonShowMode property.