[fix] fix system_chinese_font_ usage to avoid dangling font pointer after closing stream window

src/gui/render.cpp

@@ -681,7 +681,7 @@ int Render::CreateMainWindow() {
   // for window region action
   SDL_SetWindowHitTest(main_window_, HitTestCallback, this);
 
-  SetupFontAndStyle();
+  SetupFontAndStyle(true);
 
   ImGuiStyle& style = ImGui::GetStyle();
   style.ScaleAllSizes(dpi_scale_);
@@ -750,7 +750,7 @@ int Render::CreateStreamWindow() {
   // for window region action
   SDL_SetWindowHitTest(stream_window_, HitTestCallback, this);
 
-  SetupFontAndStyle();
+  SetupFontAndStyle(false);
 
   SDL_SetRenderScale(stream_renderer_, dpi_scale_, dpi_scale_);
 
@@ -793,7 +793,7 @@ int Render::DestroyStreamWindow() {
   return 0;
 }
 
-int Render::SetupFontAndStyle() {
+int Render::SetupFontAndStyle(bool main_window) {
   float font_size = 32.0f;
 
   // Setup Dear ImGui style
@@ -815,7 +815,11 @@ int Render::SetupFontAndStyle() {
   // Load system Chinese font as fallback
   config.MergeMode = false;
   config.FontDataOwnedByAtlas = false;
-  system_chinese_font_ = nullptr;
+  if (main_window) {
+    main_windows_system_chinese_font_ = nullptr;
+  } else {
+    stream_windows_system_chinese_font_ = nullptr;
+  }
 
 #if defined(_WIN32)
   // Windows: Try Microsoft YaHei (微软雅黑) first, then SimSun (宋体)
@@ -841,21 +845,38 @@ int Render::SetupFontAndStyle() {
     std::ifstream font_file(font_paths[i], std::ios::binary);
     if (font_file.good()) {
       font_file.close();
-      system_chinese_font_ =
+      if (main_window) {
+        main_windows_system_chinese_font_ =
             io.Fonts->AddFontFromFileTTF(font_paths[i], font_size, &config,
                                          io.Fonts->GetGlyphRangesChineseFull());
-      if (system_chinese_font_ != nullptr) {
+        if (main_windows_system_chinese_font_ != nullptr) {
+          LOG_INFO("Loaded system Chinese font: {}", font_paths[i]);
+          break;
+        }
+      } else {
+        stream_windows_system_chinese_font_ =
+            io.Fonts->AddFontFromFileTTF(font_paths[i], font_size, &config,
+                                         io.Fonts->GetGlyphRangesChineseFull());
+        if (stream_windows_system_chinese_font_ != nullptr) {
           LOG_INFO("Loaded system Chinese font: {}", font_paths[i]);
           break;
         }
       }
     }
+  }
 
   // If no system font found, use default font
-  if (system_chinese_font_ == nullptr) {
-    system_chinese_font_ = io.Fonts->AddFontDefault(&config);
+  if (main_window) {
+    if (main_windows_system_chinese_font_ == nullptr) {
+      main_windows_system_chinese_font_ = io.Fonts->AddFontDefault(&config);
       LOG_WARN("System Chinese font not found, using default font");
     }
+  } else {
+    if (stream_windows_system_chinese_font_ == nullptr) {
+      stream_windows_system_chinese_font_ = io.Fonts->AddFontDefault(&config);
+      LOG_WARN("System Chinese font not found, using default font");
+    }
+  }
 
   ImGui::StyleColorsLight();
 

src/gui/render.h

@@ -180,7 +180,7 @@ class Render {
   int DestroyMainWindow();
   int CreateStreamWindow();
   int DestroyStreamWindow();
-  int SetupFontAndStyle();
+  int SetupFontAndStyle(bool main_window);
   int DestroyMainWindowContext();
   int DestroyStreamWindowContext();
   int DrawMainWindow();
@@ -313,7 +313,8 @@ class Render {
   SDL_Window* main_window_ = nullptr;
   SDL_Renderer* main_renderer_ = nullptr;
   ImGuiContext* main_ctx_ = nullptr;
-  ImFont* system_chinese_font_ = nullptr;  // System Chinese font for fallback
+  ImFont* main_windows_system_chinese_font_ = nullptr;
+  ImFont* stream_windows_system_chinese_font_ = nullptr;
   bool exit_ = false;
   const int sdl_refresh_ms_ = 16;  // ~60 FPS
 #if _WIN32

src/gui/windows/request_permission_window.mm

@@ -138,8 +138,8 @@ int Render::RequestPermissionWindow() {
   ImGui::SetWindowFontScale(0.3f);
 
   // use system font
-  if (system_chinese_font_ != nullptr) {
-    ImGui::PushFont(system_chinese_font_);
+  if (main_windows_system_chinese_font_ != nullptr) {
+    ImGui::PushFont(main_windows_system_chinese_font_);
   }
 
   ImGui::SetCursorPosY(ImGui::GetCursorPosY() + ImGui::GetTextLineHeight() + 5.0f);
@@ -191,7 +191,7 @@ int Render::RequestPermissionWindow() {
   ImGui::SetWindowFontScale(0.45f);
 
   // pop system font
-  if (system_chinese_font_ != nullptr) {
+  if (main_windows_system_chinese_font_ != nullptr) {
     ImGui::PopFont();
   }
 

src/gui/windows/update_notification_window.cpp

@@ -111,8 +111,8 @@ int Render::UpdateNotificationWindow() {
     float scrollable_height =
         window_height - UPDATE_NOTIFICATION_RESERVED_HEIGHT;
 
-    if (system_chinese_font_ != nullptr) {
-      ImGui::PushFont(system_chinese_font_);
+    if (main_windows_system_chinese_font_ != nullptr) {
+      ImGui::PushFont(main_windows_system_chinese_font_);
     }
     // scrollable content area
     ImGui::SetCursorPosX(window_width * 0.05f);
@@ -163,7 +163,7 @@ int Render::UpdateNotificationWindow() {
     ImGui::EndChild();
 
     // pop system font
-    if (system_chinese_font_ != nullptr) {
+    if (main_windows_system_chinese_font_ != nullptr) {
       ImGui::PopFont();
     }