| 1 | #[derive(Debug)] |
| 2 | pub struct ContentList<T> { |
| 3 | pub list: Vec<T>, |
| 4 | pub index: usize, |
| 5 | } |
| 6 | |
| 7 | impl<T> ContentList<T> { |
| 8 | pub fn new() -> Self { |
| 9 | Self { |
| 10 | list: Vec::new(), |
| 11 | index: 0, |
| 12 | } |
| 13 | } |
| 14 | |
| 15 | pub fn next(&mut self) { |
| 16 | if let Some(last) = self.list.len().checked_sub(1) { |
| 17 | self.index = self.index.saturating_add(1).min(last); |
| 18 | } |
| 19 | } |
| 20 | |
| 21 | pub fn prev(&mut self) { |
| 22 | self.index = self.index.saturating_sub(1); |
| 23 | } |
| 24 | } |
| 25 | |
| 26 | impl<T> Default for ContentList<T> { |
| 27 | fn default() -> Self { |
| 28 | Self::new() |
| 29 | } |
| 30 | } |