feat(gtk): Add indicator for dropdown state

Closes #20

gtk/src/widgets/mod.rs

@@ -52,20 +52,44 @@ impl DeviceWidget {
             ..show();
         };
 
-        let revealer = gtk::Revealer::new();
+        let dropdown_image = gtk::ImageBuilder::new()
+            .icon_name("pan-end-symbolic")
+            .icon_size(gtk::IconSize::Menu.into())
+            .halign(gtk::Align::Start)
+            .valign(gtk::Align::Center)
+            .build();
+
+        let dropdown_image_ = dropdown_image.downgrade();
+        let revealer = cascade! {
+            gtk::Revealer::new();
+            ..connect_property_reveal_child_notify(move |revealer| {
+                dropdown_image_.upgrade()
+                    .expect("dropdown image did not exist")
+                    .set_from_icon_name(
+                        Some(if revealer.get_reveal_child() {
+                            "pan-down-symbolic"
+                        } else {
+                            "pan-end-symbolic"
+                        }),
+                        gtk::IconSize::Menu
+                    );
+            });
+        };
 
         let event_box = cascade! {
             gtk::EventBoxBuilder::new()
                 .can_focus(false)
+                .hexpand(true)
                 .events(gdk::EventMask::BUTTON_PRESS_MASK)
                 .build();
             ..add(&cascade! {
                 gtk::GridBuilder::new()
                     .column_spacing(12)
                     .build();
-                ..attach(&device, 0, 0, 1, 1);
-                ..attach(&label, 0, 1, 1, 1);
-                ..attach(&stack, 1, 0, 1, 2);
+                ..attach(&dropdown_image, 0, 0, 1, 2);
+                ..attach(&device, 1, 0, 1, 1);
+                ..attach(&label, 1, 1, 1, 1);
+                ..attach(&stack, 2, 0, 1, 2);
             });
         };
 

notify/build.rs

@@ -1,4 +1,4 @@
-use std::{fs::File, env, io::Write};
+use std::{env, fs::File, io::Write};
 
 markup::define! {
     Service<'a>(description: &'a str, appid: &'a str, exec: &'a str) {
@@ -40,14 +40,14 @@ fn main() {
 
     let timer = Timer {
         description: "Checks for new firmware every day",
-        appid: &appid,
-        minutes: 1440
+        appid:       &appid,
+        minutes:     1440,
     };
 
     let service = Service {
         description: "Check for firmware updates, and display a notification if found",
-        appid: &appid,
-        exec: &exec
+        appid:       &appid,
+        exec:        &exec,
     };
 
     File::create(timer_path)
@@ -59,4 +59,4 @@ fn main() {
         .expect("failed to create service service")
         .write_all(service.to_string().as_bytes())
         .expect("failed to write service service");
-}
+}