Add 'Open' button to open a file

src/main.rs

@@ -2,19 +2,20 @@ use std::{io, path::Path, sync::Arc};
 
 use iced::{
     executor,
-    widget::{column, text, text_editor},
+    widget::{button, column, row, text, text_editor},
     Application, Command, Element, Settings, Theme,
 };
 
 #[derive(Debug, Clone)]
 enum Message {
+    Open,
     Edit(text_editor::Action),
-    FileOpened(Result<Arc<String>, io::ErrorKind>),
+    FileOpened(Result<Arc<String>, Error>),
 }
 
 struct BookManagerApp {
     book_content: text_editor::Content,
-    io_error: Option<io::ErrorKind>,
+    io_error: Option<Error>,
 }
 
 impl Application for BookManagerApp {
@@ -47,16 +48,20 @@ impl Application for BookManagerApp {
                 Ok(content) => self.book_content = text_editor::Content::with_text(&content),
                 Err(error) => self.io_error = Some(error),
             },
+            Message::Open => {
+                return Command::perform(pick_file(), Message::FileOpened);
+            }
         }
 
         Command::none()
     }
 
     fn view(&self) -> Element<'_, Self::Message> {
+        let controls = row![button("Open").on_press(Message::Open)];
         let hello_world = text("Hello, world!");
         let active_editor = text_editor(&self.book_content).on_action(Message::Edit);
 
-        column![hello_world, active_editor]
+        column![hello_world, controls, active_editor]
             .spacing(10)
             .padding(10)
             .into()
@@ -71,9 +76,25 @@ fn main() -> iced::Result {
     BookManagerApp::run(Settings::default())
 }
 
-async fn load_file(path: impl AsRef<Path>) -> Result<Arc<String>, io::ErrorKind> {
+#[derive(Debug, Clone)]
+enum Error {
+    DialogClosed,
+    IO(io::ErrorKind),
+}
+
+async fn load_file(path: impl AsRef<Path>) -> Result<Arc<String>, Error> {
     tokio::fs::read_to_string(path)
         .await
         .map(Arc::new)
         .map_err(|error| error.kind())
+        .map_err(Error::IO)
+}
+
+async fn pick_file() -> Result<Arc<String>, Error> {
+    let file_handle = rfd::AsyncFileDialog::new()
+        .set_title("Choose a file...")
+        .pick_file()
+        .await
+        .ok_or(Error::DialogClosed)?;
+    load_file(file_handle.path()).await
 }