Tableau filters offer dashboard creators numerous customization options to increase their analytical usefulness and flexibility. You can find these options in a filter’s drop-down menu. For example, the drop-down menu for a filter on dimensional data is as follows:
The dashboard creator can choose the filter mode (Single Value, Multiple Values, and so on), whether to show the “All” value, whether to show the Apply button, and whether to show various filter options buttons: Include/Exclude, Control Types, More/Fewer, and All Values. These filter options give the end-user of the dashboard control over the behavior of the filter. While this additional control can be beneficial to some end-users, many dashboard end-users are unfamiliar with these additional options and may find them confusing, especially if they are unfamiliar with Tableau. And most importantly for this article, these filter options make filters more difficult to use for keyboard users.
The filter in the example above has multiple of these options enabled. When hovering over the filter with the mouse, the filter displays buttons to activate some of these options in the top right:
In this example, the filter options buttons control whether the filter dropdown shows all values in the data source, shows only values from the data source relevant to the current state of the dashboard, and whether the filter acts to include or exclude values. To access these buttons with the keyboard, the end-user must first use the Tab key to move key focus to the filter control and then navigate in reverse (Shift+Tab) to get to each of the additional filter options buttons. We designed keyboard navigation for filters this way so that these buttons were not always in the key focus order when navigating through the dashboard in the forward direction as we expect that they are relatively infrequently used. Unfortunately, this design choice complicates navigating the dashboard in reverse and makes it difficult for the end-user to access these buttons with the keyboard.
Because of their potential to increase end-user confusion and introduce unnecessary difficulty in keyboard navigation, a best practice for accessibility is to disable any unnecessary filter options. Removing the Control Types, More Fewer, and All Values buttons in the above example will make the resulting filter less confusing and easier to use for the dashboard end-user, especially if they are using the keyboard to interact with the dashboard:
The resulting filter will then have none of the additional filter options buttons available, making it much more self-explanatory for an uninitiated end-user and easier to navigate with the keyboard, both core principles for improved accessibility:
Small refinements like these can go a long way toward making your dashboards as accessible as possible for all of your end-users.
