update example modes

examples/mode_00.rs

@@ -1,3 +1,37 @@
-//! Mode 0: Direct draw
-use ::{std::sync::{Arc, RwLock}, ratatui::style::Color, tengri::*};
-fn main () {}
+//! Mode 00: Direct draw, direct control
+
+use ::std::sync::{Arc, RwLock};
+use ::crossterm::event::{Event::*, KeyEvent, KeyCode::*};
+use ::ratatui::style::Color;
+use ::tengri::{*, lang::*};
+
+tui_app!(State {
+    /** User-controllable value. */
+    cursor:  usize,
+});
+
+tui_view!(self: State {
+    thunk(|to: &mut Tui|{
+        let cursor = format!("Cursor: {}", self.cursor);
+        let _ = "DEMO [MODE 00]".align_sw().draw(to);
+        let _ = ShowSize.align_se().draw(to);
+        let _ = format!("Cursor: {}", self.cursor).align_c().draw(to);
+        Ok(Some(to.area()))
+    })
+});
+
+tui_keys!(self: State, input {
+    Ok(if let Key(KeyEvent { code, .. }) = input.0 {
+        match code {
+            Up | Right  => {
+                self.cursor = (self.cursor + 1) % 10;
+                ()
+            },
+            Down | Left => {
+                self.cursor = if self.cursor > 0 { self.cursor - 1 } else { 10 - 1 };
+                ()
+            },
+            _ => {}
+        }
+    })
+});