You can: use SetPanelAttribute ( tabpanel_1_handle, ATTR_SCROLL_BARS, VAL_HORIZ_SCROLL_BAR);
But you shouldn't (see the design considerations here😞
- Don’t Use Scrolling Inside Panes - Scrollbars are an added encumbrance to users interacting with module tabs: to access the information that they are looking for, not only do they have to click on tab controls, but they also need to use scrollbars to see if the content they want is farther down the pane. The need for scrollbars inside panes outlines an issue with regards to the length of the pane information or the design of the module tabs; either the content being presented is too long for the module tabs design pattern, or that the pane area is not tall enough for your content. Consider revising content for terseness, extending the height of the pane area, and/or allowing for variable height of the pane area depending on the pane information length of the active pane.