opt: dark theme, add follow system mode

src/flutter.rs

@@ -379,8 +379,8 @@ pub mod connection_manager {
             );
         }
 
-        fn change_theme(&self, dark: bool) {
-            self.push_event("theme", vec![("dark", &dark.to_string())]);
+        fn change_theme(&self, dark: String) {
+            self.push_event("theme", vec![("dark", &dark)]);
         }
 
         fn change_language(&self) {

src/flutter_ffi.rs

@@ -692,10 +692,10 @@ fn main_broadcast_message(data: &HashMap<&str, &str>) {
     }
 }
 
-pub fn main_change_theme(dark: bool) {
+pub fn main_change_theme(dark: String) {
     main_broadcast_message(&HashMap::from([
         ("name", "theme"),
-        ("dark", &dark.to_string()),
+        ("dark", &dark),
     ]));
     send_to_cm(&crate::ipc::Data::Theme(dark));
 }

src/ipc.rs

@@ -182,7 +182,7 @@ pub enum Data {
     #[cfg(not(any(target_os = "android", target_os = "ios", feature = "cli")))]
     Mouse(DataMouse),
     Control(DataControl),
-    Theme(bool),
+    Theme(String),
     Language(String),
     Empty,
 }

src/ui/cm.rs

@@ -48,7 +48,7 @@ impl InvokeUiCM for SciterHandler {
         self.call("newMessage", &make_args!(id, text));
     }
 
-    fn change_theme(&self, _dark: bool) {
+    fn change_theme(&self, _dark: String) {
         // TODO
     }
 

src/ui_cm_interface.rs

@@ -61,7 +61,7 @@ pub trait InvokeUiCM: Send + Clone + 'static + Sized {
 
     fn new_message(&self, id: i32, text: String);
 
-    fn change_theme(&self, dark: bool);
+    fn change_theme(&self, dark: String);
 
     fn change_language(&self);
 }