fix: macOS crash - replace drawsBackground KVC with _setDrawsBackground

- Wry 0.54+ parent view doesn't support drawsBackground KVC
- Recursively find WKWebView in view hierarchy
- Use _setDrawsBackground: on WKWebView directly
- Fixes NSUnknownKeyException crash on macOS

Author: 502647092

src-tauri/src/main.rs

@@ -11,6 +11,31 @@ use miaoclaw_lib::commands::*;
 use miaoclaw_lib::config::ConfigManager;
 use miaoclaw_lib::plugin::PluginEngine;
 
+/// macOS: 递归遍历子视图，找到 WKWebView 并设置透明背景
+#[cfg(target_os = "macos")]
+unsafe fn set_webview_transparent(view: cocoa::base::id) {
+    use cocoa::appkit::NSView;
+    use cocoa::base::{id, nil, NO};
+    use objc::{msg_send, sel, sel_impl, class};
+
+    // 检查是否是 WKWebView
+    let wk_class = class!(WKWebView);
+    let is_wk: bool = msg_send![view, isKindOfClass: wk_class];
+    if is_wk {
+        // WKWebView 支持 _setDrawsBackground:
+        let _: () = msg_send![view, _setDrawsBackground: NO];
+        return;
+    }
+
+    // 递归子视图
+    let subviews: id = view.subviews();
+    let count: usize = msg_send![subviews, count];
+    for i in 0..count {
+        let subview: id = msg_send![subviews, objectAtIndex: i];
+        set_webview_transparent(subview);
+    }
+}
+
 fn main() {
     tracing_subscriber::fmt::init();
 
@@ -192,9 +217,8 @@ fn main() {
             #[cfg(target_os = "macos")]
             {
                 if let Some(window) = app.get_webview_window("pet") {
-                    use cocoa::appkit::{NSColor, NSWindow};
+                    use cocoa::appkit::{NSColor, NSWindow, NSView};
                     use cocoa::base::{id, nil, NO};
-                    use cocoa::foundation::NSString;
                     use objc::{msg_send, sel, sel_impl};
 
                     let ns_window = window.ns_window().unwrap() as id;
@@ -204,9 +228,9 @@ fn main() {
                         ns_window.setOpaque_(NO);
                         ns_window.setHasShadow_(NO);
 
-                        let ns_view = window.ns_view().unwrap() as id;
-                        let key = NSString::alloc(nil).init_str("drawsBackground");
-                        let _: () = msg_send![ns_view, setValue: NO forKey: key];
+                        // 遍历子视图找到 WKWebView 并设置透明
+                        let content_view: id = ns_window.contentView();
+                        set_webview_transparent(content_view);
                     }
                 }
             }