# Roller (/examples/widgets/roller) Scrollable cylindrical selector for picking one option from a fixed list, configured via `lv_roller_set_options`. Infinite month roller [#infinite-month-roller] Pick a month from a wrap-around roller and log the selection. A centered `lv_roller` is populated with the twelve English month names in `LV_ROLLER_MODE_INFINITE`, so scrolling past December wraps back to January. Four rows are visible at once via `lv_roller_set_visible_row_count`. An `LV_EVENT_ALL` handler prints the current selection string on `LV_EVENT_VALUE_CHANGED`. Rollers sharing a selected-row style [#rollers-sharing-a-selected-row-style] One `LV_PART_SELECTED` style is reused across three number rollers of different widths. A shared style for `LV_PART_SELECTED` swaps in `lv_font_montserrat_22` with a pink fill and red border. Three `LV_ROLLER_MODE_NORMAL` rollers list numbers `1..10`: a 100 px left-aligned roller with a green vertical gradient background and two visible rows, a default-width center roller with three visible rows, and an 80 px right-aligned roller with four visible rows. Each roller starts on a different selection (2, 5, 8) with `LV_ANIM_OFF` and logs on `LV_EVENT_VALUE_CHANGED`. Roller with top and bottom fade [#roller-with-top-and-bottom-fade] Fade the roller edges to black using a generated bitmap mask. The active screen is tinted `LV_PALETTE_BLUE_GREY` and a month roller in `LV_ROLLER_MODE_NORMAL` takes a style that paints it black with white text and no border. A 130x150 `LV_COLOR_FORMAT_L8` draw buffer is filled on a canvas with two `LV_GRAD_DIR_VER` rectangles (black-to-white on top, white-to-black on bottom), leaving the middle opaque. The resulting buffer is attached through `lv_obj_set_style_bitmap_mask_src` so the first and last rows fade out.