Refactored to require handlers to specify the components they rely on and to specify when they are ready. This fixes a lot of bugs with the UI when users try to press buttons while the application is still loading.

src/models/mod.rs

@@ -52,6 +52,10 @@ impl ScrollableText {
   pub fn get_text(&self) -> String {
     self.items.join("\n")
   }
+
+  pub fn is_empty(&self) -> bool {
+    self.items.is_empty()
+  }
 }
 
 impl Scrollable for ScrollableText {

src/models/model_tests.rs

@@ -41,6 +41,18 @@ mod tests {
     assert_str_eq!(scrollable_text.get_text(), test_text);
   }
 
+  #[test]
+  fn test_scrollable_text_is_empty() {
+    let scrollable_text = ScrollableText::default();
+
+    assert!(scrollable_text.is_empty());
+
+    let test_text = "Test \nString";
+    let scrollable_text = ScrollableText::with_string(test_text.to_owned());
+
+    assert!(!scrollable_text.is_empty());
+  }
+
   #[test]
   fn test_scrollable_text_scroll() {
     let mut scrollable_text = ScrollableText::with_string("Test \nString".to_owned());

src/models/stateful_list.rs

@@ -92,4 +92,8 @@ where
   pub fn current_selection(&self) -> &T {
     &self.items[self.state.selected().unwrap_or(0)]
   }
+
+  pub fn is_empty(&self) -> bool {
+    self.items.is_empty()
+  }
 }

src/models/stateful_list_tests.rs

@@ -102,6 +102,17 @@ mod tests {
     assert_eq!(stateful_list.state.selected(), Some(0));
   }
 
+  #[test]
+  fn test_stateful_list_is_empty() {
+    let mut stateful_list = create_test_stateful_list();
+
+    assert!(!stateful_list.is_empty());
+
+    stateful_list = StatefulList::default();
+
+    assert!(stateful_list.is_empty());
+  }
+
   fn create_test_stateful_list() -> StatefulList<&'static str> {
     let mut stateful_list = StatefulList::default();
     stateful_list.set_items(vec!["Test 1", "Test 2"]);

src/models/stateful_table.rs

@@ -302,4 +302,8 @@ where
   pub fn reset_search(&mut self) {
     self.search = None;
   }
+
+  pub fn is_empty(&self) -> bool {
+    self.items.is_empty()
+  }
 }

src/models/stateful_table_tests.rs

@@ -638,6 +638,17 @@ mod tests {
     assert_eq!(stateful_table.search, None);
   }
 
+  #[test]
+  fn test_stateful_table_is_empty() {
+    let mut stateful_table = create_test_stateful_table();
+
+    assert!(!stateful_table.is_empty());
+
+    stateful_table = StatefulTable::default();
+
+    assert!(stateful_table.is_empty());
+  }
+
   fn create_test_stateful_table() -> StatefulTable<&'static str> {
     let mut stateful_table = StatefulTable::default();
     stateful_table.set_items(vec!["Test 1", "Test 2"]);