egui/crates/egui_demo_lib/src/demo/tests/grid_test.rs

#[derive(PartialEq)]
pub struct GridTest {
    num_cols: usize,
    num_rows: usize,
    min_col_width: f32,
    max_col_width: f32,
    text_length: usize,
}

impl Default for GridTest {
    fn default() -> Self {
        Self {
            num_cols: 4,
            num_rows: 4,
            min_col_width: 10.0,
            max_col_width: 200.0,
            text_length: 10,
        }
    }
}

impl crate::Demo for GridTest {
    fn name(&self) -> &'static str {
        "Grid Test"
    }

    fn show(&mut self, ctx: &egui::Context, open: &mut bool) {
        egui::Window::new(self.name()).open(open).show(ctx, |ui| {
            use crate::View as _;
            self.ui(ui);
        });
    }
}

impl crate::View for GridTest {
    fn ui(&mut self, ui: &mut egui::Ui) {
        ui.add(
            egui::Slider::new(&mut self.min_col_width, 0.0..=400.0).text("Minimum column width"),
        );
        ui.add(
            egui::Slider::new(&mut self.max_col_width, 0.0..=400.0).text("Maximum column width"),
        );
        ui.add(egui::Slider::new(&mut self.num_cols, 0..=5).text("Columns"));
        ui.add(egui::Slider::new(&mut self.num_rows, 0..=20).text("Rows"));

        ui.separator();

        let words = [
            "random", "words", "in", "a", "random", "order", "that", "just", "keeps", "going",
            "with", "some", "more",
        ];

        egui::Grid::new("my_grid")
            .striped(true)
            .min_col_width(self.min_col_width)
            .max_col_width(self.max_col_width)
            .show(ui, |ui| {
                for row in 0..self.num_rows {
                    for col in 0..self.num_cols {
                        if col == 0 {
                            ui.label(format!("row {row}"));
                        } else {
                            let word_idx = row * 3 + col * 5;
                            let word_count = (row * 5 + col * 75) % 13;
                            let mut string = String::new();
                            for word in words.iter().cycle().skip(word_idx).take(word_count) {
                                string += word;
                                string += " ";
                            }
                            ui.label(string);
                        }
                    }
                    ui.end_row();
                }
            });

        ui.separator();
        ui.add(egui::Slider::new(&mut self.text_length, 1..=40).text("Text length"));
        egui::Grid::new("parent grid").striped(true).show(ui, |ui| {
            ui.vertical(|ui| {
                ui.label("Vertical nest1");
                ui.label("Vertical nest2");
            });
            ui.label("First row, second column");
            ui.end_row();

            ui.horizontal(|ui| {
                ui.label("Horizontal nest1");
                ui.label("Horizontal nest2");
            });
            ui.label("Second row, second column");
            ui.end_row();

            ui.scope(|ui| {
                ui.label("Scope nest 1");
                ui.label("Scope nest 2");
            });
            ui.label("Third row, second column");
            ui.end_row();

            egui::Grid::new("nested grid").show(ui, |ui| {
                ui.label("Grid nest11");
                ui.label("Grid nest12");
                ui.end_row();
                ui.label("Grid nest21");
                ui.label("Grid nest22");
                ui.end_row();
            });
            ui.label("Fourth row, second column");
            ui.end_row();

            let mut dyn_text = String::from("O");
            dyn_text.extend(std::iter::repeat_n('h', self.text_length));
            ui.label(dyn_text);
            ui.label("Fifth row, second column");
            ui.end_row();
        });

        ui.vertical_centered(|ui| {
            egui::reset_button(ui, self, "Reset");
            ui.add(crate::egui_github_link_file!());
        });
    }
}