Fixes possible duplicate objc class registration.

This can happen in environments like plugins, where cacao can exist multiple times and thus tries to create and register its objc classes more than once.

src/appkit/app/class.rs

@@ -12,12 +12,17 @@ use objc::runtime::Class;
 pub(crate) fn register_app_class() -> *const Class {
     static mut APP_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTApplication";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { APP_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSApplication);
-        let decl = ClassDecl::new("RSTApplication", superclass).unwrap();
+            let decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
             APP_CLASS = decl.register();
         });
+    }
 
     unsafe { APP_CLASS }
 }

src/appkit/app/delegate.rs

@@ -297,10 +297,14 @@ extern "C" fn delegate_handles_key<T: AppDelegate>(this: &Object, _: Sel, _: id,
 pub(crate) fn register_app_delegate_class<T: AppDelegate + AppDelegate>() -> *const Class {
     static mut DELEGATE_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTAppDelegate";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { DELEGATE_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSObject);
-        let mut decl = ClassDecl::new("RSTAppDelegate", superclass).unwrap();
+            let mut decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
 
             decl.add_ivar::<usize>(APP_PTR);
 
@@ -464,6 +468,7 @@ pub(crate) fn register_app_delegate_class<T: AppDelegate + AppDelegate>() -> *co
 
             DELEGATE_CLASS = decl.register();
         });
+    }
 
     unsafe { DELEGATE_CLASS }
 }

src/appkit/menu/item.rs

@@ -316,10 +316,14 @@ extern "C" fn fire_block_action(this: &Object, _: Sel, _item: id) {
 pub(crate) fn register_menu_item_class() -> *const Class {
     static mut APP_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "CacaoMenuItem";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { APP_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSMenuItem);
-        let mut decl = ClassDecl::new("CacaoMenuItem", superclass).unwrap();
+            let mut decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
             decl.add_ivar::<usize>(BLOCK_PTR);
 
             decl.add_method(sel!(dealloc), dealloc_cacao_menuitem as extern "C" fn(&Object, _));
@@ -327,6 +331,7 @@ pub(crate) fn register_menu_item_class() -> *const Class {
 
             APP_CLASS = decl.register();
         });
+    }
 
     unsafe { APP_CLASS }
 }

src/appkit/window/controller/class.rs

@@ -14,13 +14,18 @@ use crate::appkit::window::{WindowDelegate, WINDOW_DELEGATE_PTR};
 pub(crate) fn register_window_controller_class<T: WindowDelegate>() -> *const Class {
     static mut DELEGATE_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTWindowController";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { DELEGATE_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSWindowController);
-        let mut decl = ClassDecl::new("RSTWindowController", superclass).unwrap();
+            let mut decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
             decl.add_ivar::<usize>(WINDOW_DELEGATE_PTR);
             DELEGATE_CLASS = decl.register();
         });
+    }
 
     unsafe { DELEGATE_CLASS }
 }

src/button/mod.rs

@@ -345,12 +345,18 @@ impl Drop for Button {
 fn register_class() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTButton";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe {
+            VIEW_CLASS = c;
+        }
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSButton);
-        let decl = ClassDecl::new("RSTButton", superclass).unwrap();
+            let decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
             VIEW_CLASS = decl.register();
         });
-
+    }
     unsafe { VIEW_CLASS }
 }

src/color/appkit_dynamic_color.rs

@@ -261,10 +261,14 @@ extern "C" fn color_with_system_effect(this: &Object, _: Sel, effect: NSInteger)
 pub(crate) fn register_class() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "CacaoDynamicColor";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { VIEW_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSColor);
-        let mut decl = ClassDecl::new("CacaoDynamicColor", superclass).unwrap();
+            let mut decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
 
             // These methods all need to be forwarded, so let's hook them up.
             decl.add_method(sel!(colorSpace), color_space as extern "C" fn(&Object, _) -> id);
@@ -362,6 +366,7 @@ pub(crate) fn register_class() -> *const Class {
 
             VIEW_CLASS = decl.register();
         });
+    }
 
     unsafe { VIEW_CLASS }
 }

src/image/appkit.rs

@@ -25,15 +25,20 @@ use crate::view::{ViewDelegate, VIEW_DELEGATE_PTR};
 pub(crate) fn register_image_view_class() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTImageView";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { VIEW_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSImageView);
-        let decl = ClassDecl::new("RSTImageView", superclass).unwrap();
+            let decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
 
             //decl.add_method(sel!(isFlipped), enforce_normalcy as extern "C" fn(&Object, _) -> BOOL);
 
             VIEW_CLASS = decl.register();
         });
+    }
 
     unsafe { VIEW_CLASS }
 }

src/image/uikit.rs

@@ -15,12 +15,17 @@ use crate::view::{ViewDelegate, VIEW_DELEGATE_PTR};
 pub(crate) fn register_image_view_class() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTImageView";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { VIEW_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(UIImageView);
-        let mut decl = ClassDecl::new("RSTImageView", superclass).expect("Failed to get RSTVIEW");
+            let mut decl = ClassDecl::new(CLASS_NAME, superclass).expect("Failed to get RSTVIEW");
             VIEW_CLASS = decl.register();
         });
+    }
 
     unsafe { VIEW_CLASS }
 }

src/input/appkit.rs

@@ -54,12 +54,17 @@ extern "C" fn text_should_end_editing<T: TextFieldDelegate>(this: &mut Object, _
 pub(crate) fn register_view_class() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTTextInputField";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { VIEW_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSTextField);
-        let decl = ClassDecl::new("RSTTextInputField", superclass).unwrap();
+            let decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
             VIEW_CLASS = decl.register();
         });
+    }
 
     unsafe { VIEW_CLASS }
 }

src/invoker.rs

@@ -97,16 +97,23 @@ extern "C" fn perform<F: Fn() + 'static>(this: &mut Object, _: Sel, _sender: id)
 pub(crate) fn register_invoker_class<F: Fn() + 'static>() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTTargetActionHandler";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe {
+            VIEW_CLASS = c;
+        }
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSObject);
-        let mut decl = ClassDecl::new("RSTTargetActionHandler", superclass).unwrap();
+            let mut decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
 
             decl.add_ivar::<usize>(ACTION_CALLBACK_PTR);
             decl.add_method(sel!(perform:), perform::<F> as extern "C" fn(&mut Object, _, id));
 
             VIEW_CLASS = decl.register();
         });
+    }
 
     unsafe { VIEW_CLASS }
 }

src/listview/appkit.rs

@@ -187,12 +187,17 @@ extern "C" fn dragging_exited<T: ListViewDelegate>(this: &mut Object, _: Sel, in
 pub(crate) fn register_listview_class() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &'static str = "RSTListView";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { VIEW_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSTableView);
-        let decl = ClassDecl::new("RSTListView", superclass).unwrap();
+            let decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
             VIEW_CLASS = decl.register();
         });
+    }
 
     unsafe { VIEW_CLASS }
 }

src/listview/row/appkit.rs

@@ -109,15 +109,20 @@ extern "C" fn dealloc<T: ViewDelegate>(this: &Object, _: Sel) {
 pub(crate) fn register_listview_row_class() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTTableViewRow";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { VIEW_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSView);
-        let mut decl = ClassDecl::new("RSTTableViewRow", superclass).unwrap();
+            let mut decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
 
             decl.add_method(sel!(isFlipped), enforce_normalcy as extern "C" fn(&Object, _) -> BOOL);
 
             VIEW_CLASS = decl.register();
         });
+    }
 
     unsafe { VIEW_CLASS }
 }
@@ -127,10 +132,14 @@ pub(crate) fn register_listview_row_class() -> *const Class {
 pub(crate) fn register_listview_row_class_with_delegate<T: ViewDelegate>() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTableViewRowWithDelegate";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { VIEW_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSView);
-        let mut decl = ClassDecl::new("RSTableViewRowWithDelegate", superclass).unwrap();
+            let mut decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
 
             // A pointer to the "view controller" on the Rust side. It's expected that this doesn't
             // move.
@@ -167,6 +176,7 @@ pub(crate) fn register_listview_row_class_with_delegate<T: ViewDelegate>() -> *c
 
             VIEW_CLASS = decl.register();
         });
+    }
 
     unsafe { VIEW_CLASS }
 }

src/listview/row/uikit.rs

@@ -16,12 +16,17 @@ use crate::utils::load;
 pub(crate) fn register_view_class() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTView";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { VIEW_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(UIView);
-        let mut decl = ClassDecl::new("RSTView", superclass).unwrap();
+            let mut decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
             VIEW_CLASS = decl.register();
         });
+    }
 
     unsafe { VIEW_CLASS }
 }
@@ -31,15 +36,18 @@ pub(crate) fn register_view_class() -> *const Class {
 pub(crate) fn register_view_class_with_delegate<T: ViewDelegate>() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTViewWithDelegate";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { VIEW_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(UIView);
-        let mut decl = ClassDecl::new("RSTViewWithDelegate", superclass).unwrap();
+            let mut decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
             decl.add_ivar::<usize>(VIEW_DELEGATE_PTR);
             VIEW_CLASS = decl.register();
         });
+    }
 
-    unsafe {
+    unsafe { VIEW_CLASS }
-        VIEW_CLASS
-    }
 }

src/scrollview/appkit.rs

@@ -79,12 +79,17 @@ extern "C" fn dragging_exited<T: ScrollViewDelegate>(this: &mut Object, _: Sel,
 pub(crate) fn register_scrollview_class() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &'static str = "RSTScrollView";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { VIEW_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSScrollView);
-        let decl = ClassDecl::new("RSTScrollView", superclass).unwrap();
+            let decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
             VIEW_CLASS = decl.register();
         });
+    }
 
     unsafe { VIEW_CLASS }
 }
@@ -94,10 +99,14 @@ pub(crate) fn register_scrollview_class() -> *const Class {
 pub(crate) fn register_scrollview_class_with_delegate<T: ScrollViewDelegate>() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &'static str = "RSTScrollViewWithDelegate";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { VIEW_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSScrollView);
-        let mut decl = ClassDecl::new("RSTScrollViewWithDelegate", superclass).unwrap();
+            let mut decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
 
             // A pointer to the "view controller" on the Rust side. It's expected that this doesn't
             // move.
@@ -129,6 +138,7 @@ pub(crate) fn register_scrollview_class_with_delegate<T: ScrollViewDelegate>() -
 
             VIEW_CLASS = decl.register();
         });
+    }
 
     unsafe { VIEW_CLASS }
 }

src/select/mod.rs

@@ -270,12 +270,17 @@ impl Drop for Select {
 fn register_class() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "CacaoSelect";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { VIEW_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSPopUpButton);
-        let decl = ClassDecl::new("CacaoSelect", superclass).unwrap();
+            let decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
             VIEW_CLASS = decl.register();
         });
+    }
 
     unsafe { VIEW_CLASS }
 }

src/switch.rs

@@ -180,12 +180,19 @@ impl Drop for Switch {
 fn register_class() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTSwitch";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe {
+            VIEW_CLASS = c;
+        }
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSButton);
-        let decl = ClassDecl::new("RSTSwitch", superclass).unwrap();
+            let decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
             VIEW_CLASS = decl.register();
         });
+    }
 
     unsafe { VIEW_CLASS }
 }

src/text/label/appkit.rs

@@ -25,12 +25,17 @@ use crate::utils::load;
 pub(crate) fn register_view_class() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTTextField";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { VIEW_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSTextField);
-        let decl = ClassDecl::new("RSTTextField", superclass).unwrap();
+            let decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
             VIEW_CLASS = decl.register();
         });
+    }
 
     unsafe { VIEW_CLASS }
 }
@@ -40,10 +45,14 @@ pub(crate) fn register_view_class() -> *const Class {
 pub(crate) fn register_view_class_with_delegate<T: LabelDelegate>() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTTextFieldWithDelegate";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { VIEW_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSView);
-        let mut decl = ClassDecl::new("RSTTextFieldWithDelegate", superclass).unwrap();
+            let mut decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
 
             // A pointer to the "view controller" on the Rust side. It's expected that this doesn't
             // move.
@@ -51,6 +60,7 @@ pub(crate) fn register_view_class_with_delegate<T: LabelDelegate>() -> *const Cl
 
             VIEW_CLASS = decl.register();
         });
+    }
 
     unsafe { VIEW_CLASS }
 }

src/uikit/app/class.rs

@@ -12,12 +12,17 @@ use objc::runtime::Class;
 pub(crate) fn register_app_class() -> *const Class {
     static mut APP_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTApplication";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { APP_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(UIApplication);
-        let decl = ClassDecl::new("RSTApplication", superclass).unwrap();
+            let decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
             APP_CLASS = decl.register();
         });
+    }
 
     unsafe { APP_CLASS }
 }

src/uikit/app/delegate.rs

@@ -51,10 +51,14 @@ extern "C" fn configuration_for_scene_session<T: AppDelegate>(this: &Object, _:
 pub(crate) fn register_app_delegate_class<T: AppDelegate>() -> *const Class {
     static mut DELEGATE_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTAppDelegate";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { DELEGATE_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSObject);
-        let mut decl = ClassDecl::new("RSTAppDelegate", superclass).unwrap();
+            let mut decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
 
             // Launching Applications
             decl.add_method(
@@ -74,6 +78,7 @@ pub(crate) fn register_app_delegate_class<T: AppDelegate>() -> *const Class {
 
             DELEGATE_CLASS = decl.register();
         });
+    }
 
     unsafe { DELEGATE_CLASS }
 }

src/uikit/scene/delegate.rs

@@ -62,11 +62,15 @@ extern "C" fn scene_will_connect_to_session_with_options<T: WindowSceneDelegate>
 pub(crate) fn register_window_scene_delegate_class<T: WindowSceneDelegate, F: Fn() -> Box<T>>() -> *const Class {
     static mut DELEGATE_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTWindowSceneDelegate";
 
-    use objc::runtime::{class_addProtocol, Protocol};
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { DELEGATE_CLASS = c };
+    } else {
+        use objc::runtime::Protocol;
         INIT.call_once(|| unsafe {
             let superclass = class!(UIResponder);
-        let mut decl = ClassDecl::new("RSTWindowSceneDelegate", superclass).unwrap();
+            let mut decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
 
             let p = Protocol::get("UIWindowSceneDelegate").unwrap();
 
@@ -86,6 +90,7 @@ pub(crate) fn register_window_scene_delegate_class<T: WindowSceneDelegate, F: Fn
             // Launching Applications
             DELEGATE_CLASS = decl.register();
         });
+    }
 
     unsafe { DELEGATE_CLASS }
 }

src/view/appkit.rs

@@ -94,10 +94,14 @@ extern "C" fn update_layer(this: &Object, _: Sel) {
 pub(crate) fn register_view_class() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTView";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { VIEW_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(NSView);
-        let mut decl = ClassDecl::new("RSTView", superclass).unwrap();
+            let mut decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
 
             decl.add_method(sel!(isFlipped), enforce_normalcy as extern "C" fn(&Object, _) -> BOOL);
             decl.add_method(sel!(updateLayer), update_layer as extern "C" fn(&Object, _));
@@ -107,6 +111,7 @@ pub(crate) fn register_view_class() -> *const Class {
 
             VIEW_CLASS = decl.register();
         });
+    }
 
     unsafe { VIEW_CLASS }
 }

src/view/splitviewcontroller/ios.rs

@@ -53,20 +53,30 @@ extern "C" fn did_disappear<T: ViewDelegate>(this: &mut Object, _: Sel, animated
 pub(crate) fn register_view_controller_class<T: ViewDelegate + 'static>() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTViewController";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { VIEW_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(UIViewController);
-        let mut decl = ClassDecl::new("RSTViewController", superclass).unwrap();
+            let mut decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
 
             decl.add_ivar::<usize>(VIEW_DELEGATE_PTR);
 
             decl.add_method(sel!(viewWillAppear:), will_appear::<T> as extern "C" fn(&mut Object, _, BOOL));
             decl.add_method(sel!(viewDidAppear:), did_appear::<T> as extern "C" fn(&mut Object, _, BOOL));
-        decl.add_method(sel!(viewWillDisappear:), will_disappear::<T> as extern "C" fn(&mut Object, _, BOOL));
+            decl.add_method(
-        decl.add_method(sel!(viewDidDisappear:), did_disappear::<T> as extern "C" fn(&mut Object, _, BOOL));
+                sel!(viewWillDisappear:),
+                will_disappear::<T> as extern "C" fn(&mut Object, _, BOOL)
+            );
+            decl.add_method(
+                sel!(viewDidDisappear:),
+                did_disappear::<T> as extern "C" fn(&mut Object, _, BOOL)
+            );
 
             VIEW_CLASS = decl.register();
         });
-
+    }
     unsafe { VIEW_CLASS }
 }

src/view/uikit.rs

@@ -16,12 +16,17 @@ use crate::view::{ViewDelegate, VIEW_DELEGATE_PTR};
 pub(crate) fn register_view_class() -> *const Class {
     static mut VIEW_CLASS: *const Class = 0 as *const Class;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTView";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { VIEW_CLASS = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = class!(UIView);
-        let mut decl = ClassDecl::new("RSTView", superclass).unwrap();
+            let mut decl = ClassDecl::new(CLASS_NAME, superclass).unwrap();
             VIEW_CLASS = decl.register();
         });
+    }
 
     unsafe { VIEW_CLASS }
 }

src/webview/process_pool.rs

@@ -28,7 +28,11 @@ extern "C" fn download_delegate(this: &Object, _: Sel) -> id {
 pub fn register_process_pool() -> *const Object {
     static mut PROCESS_POOL: *const Object = 0 as *const Object;
     static INIT: Once = Once::new();
+    const CLASS_NAME: &str = "RSTWebViewProcessPool";
 
+    if let Some(c) = Class::get(CLASS_NAME) {
+        unsafe { PROCESS_POOL = c };
+    } else {
         INIT.call_once(|| unsafe {
             let superclass = Class::get("WKProcessPool").unwrap();
             let mut decl = ClassDecl::new("RSTWebViewProcessPool", superclass).unwrap();
@@ -39,6 +43,7 @@ pub fn register_process_pool() -> *const Object {
             //PROCESS_POOL = decl.register();
             PROCESS_POOL = msg_send![decl.register(), new];
         });
+    }
 
     unsafe { PROCESS_POOL }
 }