implemnt scrollable menu field. Not yet tested

stm-firmware/include/reflow-controller/ui/menu.h

@@ -47,7 +47,9 @@ struct lcd_menu {
 };
 
 struct menu_list {
+	void (*update_display)(uint8_t row, const char *data);
 	const char **entry_names;
+	uint32_t entry_count;
 	uint32_t currently_selected;
 	const menu_func_t *submenu_list;
 };
@@ -62,6 +64,12 @@ void menu_entry_enter(struct lcd_menu *menu, menu_func_t parent_func, bool handl
 
 void menu_override_lcd_output(struct lcd_menu *menu, uint8_t row_num, const char *text);
 
-void menu_list_display(struct menu_list *list, uint8_t top_row, uint8_t bottom_row);
+void menu_list_display(struct menu_list *list, uint32_t top_row, uint32_t bottom_row);
+
+void menu_list_compute_count(struct menu_list *list);
+
+void menu_list_scroll_down(struct menu_list *list);
+
+void menu_list_scroll_up(struct menu_list *list);
 
 #endif /* __MENU_H__ */

stm-firmware/ui/menu.c

@@ -20,6 +20,7 @@
 
 #include <reflow-controller/ui/menu.h>
 #include <stddef.h>
+#include <stdio.h>
 
 void menu_handle(struct lcd_menu *menu, int16_t rotary_encoder_delta, enum button_state push_button)
 {
@@ -95,9 +96,89 @@ void menu_override_lcd_output(struct lcd_menu *menu, uint8_t row_num, const char
 	menu->update_display(row_num, text);
 }
 
-void menu_list_display(struct menu_list *list, uint8_t top_row, uint8_t bottom_row)
+void menu_list_display(struct menu_list *list, uint32_t top_row, uint32_t bottom_row)
 {
-	(void)list;
+	uint8_t row_count;
-	(void)top_row;
+	uint32_t mid_row;
-	(void)bottom_row;
+	uint32_t count_above_mid;
+	uint32_t count_below_mid;
+	uint32_t start_index;
+	uint32_t current_row;
+	uint32_t current_idx;
+	char workbuff[64];
+
+	if (!list || !list->update_display)
+		return;
+
+	if (bottom_row < top_row)
+		return;
+
+	if (list->entry_count == 0) {
+		for (current_row = top_row; current_row <= bottom_row; current_row++) {
+			list->update_display((uint8_t)current_row, "");
+		}
+		return;
+	}
+
+	/* Calculate list parameters */
+	row_count = top_row - bottom_row + 1;
+	mid_row = (top_row + bottom_row) / 2;
+	count_above_mid = mid_row - top_row;
+	count_below_mid = bottom_row - mid_row;
+
+	/* Check if there are more elements above the and below the currently selected one that can be displayed. in this case position
+	 * active entry in center
+	 */
+	if (list->currently_selected > count_above_mid && (list->entry_count - list->currently_selected - 1) > count_below_mid) {
+		start_index = list->currently_selected - count_above_mid;
+	} else if (list->currently_selected < count_above_mid) {
+		start_index = 0;
+	} else if ((list->entry_count - list->currently_selected - 1) < count_below_mid) {
+		if (list->entry_count < row_count) {
+			start_index = 0;
+		}
+		start_index = list->entry_count - row_count;
+	} else {
+		start_index = 0;
+	}
+
+	for (current_row = top_row, current_idx = start_index; current_row <= bottom_row; current_row++, current_idx++) {
+		if (current_idx >= list->entry_count)
+			break;
+
+		snprintf(workbuff, sizeof(workbuff), "%c%s", (current_idx == list->currently_selected ? '>' : ' '), list->entry_names[current_idx]);
+		workbuff[sizeof(workbuff)-1] = 0;
+		list->update_display((uint8_t)current_row, workbuff);
+	}
+
+}
+
+void menu_list_compute_count(struct menu_list *list)
+{
+	uint32_t count = 0;
+
+	if (!list)
+		return;
+
+	for (count = 0; list->entry_names[count] != NULL; count++);
+	list->entry_count = count;
+}
+
+void menu_list_scroll_down(struct menu_list *list)
+{
+	if (!list)
+		return;
+
+	if (list->currently_selected < list->entry_count - 1) {
+		list->currently_selected++;
+	}
+}
+
+void menu_list_scroll_up(struct menu_list *list)
+{
+	if (!list)
+		return;
+
+	if (list->currently_selected > 0)
+		list->currently_selected--;
 }