Update qr_code example with theme selector

examples/qr_code/src/main.rs

@@ -1,6 +1,6 @@
 use iced::widget::qr_code::{self, QRCode};
-use iced::widget::{column, container, text, text_input};
-use iced::{Alignment, Color, Element, Length, Sandbox, Settings};
+use iced::widget::{column, container, pick_list, row, text, text_input};
+use iced::{Alignment, Element, Length, Sandbox, Settings, Theme};
 
 pub fn main() -> iced::Result {
     QRGenerator::run(Settings::default())
@@ -10,11 +10,13 @@ pub fn main() -> iced::Result {
 struct QRGenerator {
     data: String,
     qr_code: Option<qr_code::State>,
+    theme: Theme,
 }
 
 #[derive(Debug, Clone)]
 enum Message {
     DataChanged(String),
+    ThemeChanged(Theme),
 }
 
 impl Sandbox for QRGenerator {
@@ -41,21 +43,37 @@ impl Sandbox for QRGenerator {
 
                 self.data = data;
             }
+            Message::ThemeChanged(theme) => {
+                self.theme = theme;
+
+                if self.qr_code.is_some() {
+                    self.qr_code = qr_code::State::new(&self.data).ok();
+                }
+            }
         }
     }
 
     fn view(&self) -> Element<Message> {
-        let title = text("QR Code Generator")
-            .size(70)
-            .style(Color::from([0.5, 0.5, 0.5]));
+        let title = text("QR Code Generator").size(70);
 
         let input =
             text_input("Type the data of your QR code here...", &self.data)
                 .on_input(Message::DataChanged)
                 .size(30)
                 .padding(15);
 
-        let mut content = column![title, input]
+        let choose_theme = row![
+            text("Theme:"),
+            pick_list(
+                Theme::ALL,
+                Some(self.theme.clone()),
+                Message::ThemeChanged,
+            )
+        ]
+        .spacing(10)
+        .align_items(Alignment::Center);
+
+        let mut content = column![title, input, choose_theme]
             .width(700)
             .spacing(20)
             .align_items(Alignment::Center);
@@ -72,4 +90,8 @@ impl Sandbox for QRGenerator {
             .center_y()
             .into()
     }
+
+    fn theme(&self) -> Theme {
+        self.theme.clone()
+    }
 }