HomeStack: Minor refactor to wrap gtk::Stack actions.

For now the methods are private and migth not be neccesarry,
but it will be much easier to manipulate the stack from outside
with this API if it's needed and the methods are made public.

hammond-gtk/src/main.rs

@@ -5,7 +5,7 @@
     )
 )]
 #![allow(unknown_lints)]
-#![deny(unused_extern_crates, unused)]
+// #![deny(unused_extern_crates, unused)]
 
 extern crate gdk;
 extern crate gdk_pixbuf;

hammond-gtk/src/stacks/home.rs

@@ -11,11 +11,18 @@ use widgets::{EmptyView, HomeView};
 use std::rc::Rc;
 use std::sync::mpsc::Sender;
 
+#[derive(Debug, Clone)]
+enum State {
+    Home,
+    Empty,
+}
+
 #[derive(Debug, Clone)]
 pub struct HomeStack {
-    stack: gtk::Stack,
     empty: EmptyView,
     episodes: Rc<HomeView>,
+    stack: gtk::Stack,
+    state: State,
     sender: Sender<Action>,
 }
 
@@ -24,17 +31,25 @@ impl HomeStack {
         let episodes = HomeView::new(sender.clone())?;
         let empty = EmptyView::new();
         let stack = gtk::Stack::new();
+        let state = State::Empty;
 
-        stack.add_named(&episodes.container, "episodes");
+        stack.add_named(&episodes.container, "home");
         stack.add_named(&empty.container, "empty");
-        set_stack_visible(&stack)?;
 
-        Ok(HomeStack {
-            stack,
+        let mut home = HomeStack {
             empty,
             episodes,
+            stack,
+            state,
             sender,
-        })
+        };
+
+        home.determine_state()?;
+        Ok(home)
+    }
+
+    pub fn get_stack(&self) -> gtk::Stack {
+        self.stack.clone()
     }
 
     pub fn update(&mut self) -> Result<(), Error> {
@@ -45,8 +60,7 @@ impl HomeStack {
             .ok();
 
         self.replace_view()?;
-        set_stack_visible(&self.stack)?;
-        Ok(())
+        self.determine_state().map_err(From::from)
     }
 
     fn replace_view(&mut self) -> Result<(), Error> {
@@ -56,7 +70,7 @@ impl HomeStack {
 
         // Remove the old widget and add the new one
         self.stack.remove(old);
-        self.stack.add_named(&eps.container, "episodes");
+        self.stack.add_named(&eps.container, "home");
 
         // replace view in the struct too
         self.episodes = eps;
@@ -67,18 +81,30 @@ impl HomeStack {
         Ok(())
     }
 
-    pub fn get_stack(&self) -> gtk::Stack {
-        self.stack.clone()
+    #[inline]
+    fn switch_visible(&mut self, s: State) {
+        use self::State::*;
+
+        match s {
+            Home => {
+                self.stack.set_visible_child_name("home");
+                self.state = Home;
+            }
+            Empty => {
+                self.stack.set_visible_child_name("empty");
+                self.state = Empty;
+            }
+        }
+    }
+
+    #[inline]
+    fn determine_state(&mut self) -> Result<(), DataError> {
+        if is_episodes_populated()? {
+            self.switch_visible(State::Home);
+        } else {
+            self.switch_visible(State::Empty);
+        };
+
+        Ok(())
     }
 }
-
-#[inline]
-fn set_stack_visible(stack: &gtk::Stack) -> Result<(), DataError> {
-    if is_episodes_populated()? {
-        stack.set_visible_child_name("episodes");
-    } else {
-        stack.set_visible_child_name("empty");
-    };
-
-    Ok(())
-}