message: Update PaneGrid example with more complex TitleBar
diff: use iced::{
  button, executor, keyboard, pane_grid, scrollable, Align, Application,
  - Button, Column, Command, Container, Element, HorizontalAlignment, Length,
  - PaneGrid, Scrollable, Settings, Subscription, Text,
  + Button, Color, Column, Command, Container, Element, HorizontalAlignment,
  + Length, PaneGrid, Row, Scrollable, Settings, Subscription, Text,
  };
  use iced_native::{event, subscription, Event};
  @@ -141,8 +141,19 @@ impl Application for Example {
  let pane_grid = PaneGrid::new(&mut self.panes, |pane, content| {
  let is_focused = focus == Some(pane);
  - let title_bar =
  - pane_grid::TitleBar::new(format!("Pane {}", content.id))
  + let title = Row::with_children(vec![
  + Text::new("Pane").into(),
  + Text::new(content.id.to_string())
  + .color(if is_focused {
  + PANE_ID_COLOR_FOCUSED
  + } else {
  + PANE_ID_COLOR_UNFOCUSED
  + })
  + .into(),
  + ])
  + .spacing(5);
  +
  + let title_bar = pane_grid::TitleBar::new(title)
  .padding(10)
  .style(style::TitleBar { is_focused });
  @@ -165,6 +176,17 @@ impl Application for Example {
  }
  }
  +const PANE_ID_COLOR_UNFOCUSED: Color = Color::from_rgb(
  + 0xFF as f32 / 255.0,
  + 0xC7 as f32 / 255.0,
  + 0xC7 as f32 / 255.0,
  +);
  +const PANE_ID_COLOR_FOCUSED: Color = Color::from_rgb(
  + 0xFF as f32 / 255.0,
  + 0x47 as f32 / 255.0,
  + 0x47 as f32 / 255.0,
  +);
  +
  fn handle_hotkey(key_code: keyboard::KeyCode) -> Option<Message> {
  use keyboard::KeyCode;
  use pane_grid::{Axis, Direction};
  