wip: component refactor

src/device/chain.rs

@@ -67,6 +67,9 @@ pub fn render (state: &Chain, buf: &mut Buffer, area: Rect)
 }
 
 impl Focus for Chain {
+    fn unfocus (&mut self) {
+        self.focused = false
+    }
     fn focused (&self) -> Option<&Box<dyn Device>> {
         match self.focused {
             true  => self.items.get(self.focus),
@@ -80,29 +83,36 @@ impl Focus for Chain {
         }
     }
     fn handle_focus (&mut self, event: &FocusEvent) -> Usually<bool> {
-        match event {
+        Ok(match event {
             FocusEvent::Backward => {
                 if self.focus == 0 {
                     self.focus = self.items.len();
                 }
                 self.focus = self.focus - 1;
+                true
             },
             FocusEvent::Forward => {
                 self.focus = self.focus + 1;
                 if self.focus >= self.items.len() {
                     self.focus = 0;
                 }
+                true
             },
             FocusEvent::Inward => {
                 self.focused = true;
                 self.items[self.focus].handle(&AppEvent::Focus)?;
+                true
             },
             FocusEvent::Outward => {
-                self.focused = false;
-                self.items[self.focus].handle(&AppEvent::Blur)?;
+                if self.focused {
+                    self.focused = false;
+                    self.items[self.focus].handle(&AppEvent::Blur)?;
+                    true
+                } else {
+                    false
+                }
             },
-        };
-        Ok(true)
+        })
     }
 }