...

6 files changed, 55 insertions, 20 deletions

diff --git a/src/ui/DeleteLater.cpp b/src/ui/DeleteLater.cpp
index 8a40642f..f8911ae1 100644
--- a/src/ui/DeleteLater.cpp
+++ b/src/ui/DeleteLater.cpp
@@ -9,4 +9,6 @@ DeleteLaterImpl::~DeleteLaterImpl() {}
 void DeleteLaterImpl::DeleteLater() {
   GetUiApplication()->SetImmediate([this] { delete this; });
 }
+
+void DeleteLaterImpl::OnPrepareDelete() {}
 }  // namespace cru::ui
diff --git a/src/ui/components/Component.cpp b/src/ui/components/Component.cpp
index ddf65515..01db8710 100644
--- a/src/ui/components/Component.cpp
+++ b/src/ui/components/Component.cpp
@@ -1,5 +1,7 @@
 #include "cru/ui/components/Component.h"
 
+#include "cru/ui/controls/Control.h"
+
 namespace cru::ui::components {
-  
-}
+void Component::OnPrepareDelete() { GetRootControl()->RemoveFromParent(); }
+}  // namespace cru::ui::components
diff --git a/src/ui/controls/Control.cpp b/src/ui/controls/Control.cpp
index f2d4760e..3b0d4be3 100644
--- a/src/ui/controls/Control.cpp
+++ b/src/ui/controls/Control.cpp
@@ -1,5 +1,6 @@
 #include "cru/ui/controls/Control.h"
 
+#include "cru/common/log/Logger.h"
 #include "cru/platform/gui/Cursor.h"
 #include "cru/platform/gui/UiApplication.h"
 #include "cru/ui/host/WindowHost.h"
@@ -28,6 +29,11 @@ Control::Control() {
 }
 
 Control::~Control() {
+  if (host::WindowHost::IsInEventHandling()) {
+    CRU_LOG_ERROR(
+        u"Control destroyed during event handling. Please use DeleteLater.");
+  }
+
   in_destruction_ = true;
   RemoveFromParent();
 }
@@ -120,12 +126,7 @@ void Control::OnParentChangedCore(Control* old_parent, Control* new_parent) {
 void Control::OnWindowHostChangedCore(host::WindowHost* old_host,
                                       host::WindowHost* new_host) {
   if (old_host != nullptr) {
-    if (old_host->GetMouseCaptureControl() == this) {
-      old_host->CaptureMouseFor(nullptr);
-    }
-    if (old_host->GetMouseHoverControl() == this) {
-      old_host->mouse_hover_control_ = nullptr;
-    }
+    old_host->OnControlDetach(this);
   }
 
   if (!in_destruction_) {
@@ -136,4 +137,6 @@ void Control::OnWindowHostChangedCore(host::WindowHost* old_host,
     OnWindowHostChanged(old_host, new_host);
   }
 }
+
+void Control::OnPrepareDelete() { RemoveFromParent(); }
 }  // namespace cru::ui::controls
diff --git a/src/ui/controls/TextHostControlService.cpp b/src/ui/controls/TextHostControlService.cpp
index 15d9102c..d6c40a36 100644
--- a/src/ui/controls/TextHostControlService.cpp
+++ b/src/ui/controls/TextHostControlService.cpp
@@ -2,9 +2,9 @@
 
 #include "../Helper.h"
 #include "cru/common/Base.h"
-#include "cru/common/log/Logger.h"
 #include "cru/common/String.h"
 #include "cru/common/StringUtil.h"
+#include "cru/common/log/Logger.h"
 #include "cru/platform/graphics/Font.h"
 #include "cru/platform/gui/Base.h"
 #include "cru/platform/gui/Clipboard.h"
@@ -15,6 +15,7 @@
 #include "cru/platform/gui/Window.h"
 #include "cru/ui/Base.h"
 #include "cru/ui/DebugFlags.h"
+#include "cru/ui/DeleteLater.h"
 #include "cru/ui/components/Menu.h"
 #include "cru/ui/events/UiEvents.h"
 #include "cru/ui/helper/ShortcutHub.h"
@@ -149,7 +150,7 @@ std::vector<TextControlMovePattern> TextControlMovePattern::kDefaultPatterns = {
 TextHostControlService::TextHostControlService(gsl::not_null<Control*> control)
     : control_(control),
       text_host_control_(dynamic_cast<ITextHostControl*>(control.get())) {
-  context_menu_ = std::make_unique<components::PopupMenu>();
+  context_menu_ = MakeDeleteLaterPtr<components::PopupMenu>();
 
   SetUpShortcuts();
 
@@ -335,11 +336,12 @@ void TextHostControlService::SetCaretBlinkDuration(int milliseconds) {
 
 void TextHostControlService::ScrollToCaret() {
   if (const auto scroll_render_object = this->GetScrollRenderObject()) {
-    this->control_->GetWindowHost()->RunAfterLayoutStable(
-        [this, scroll_render_object]() {
-          const auto caret_rect = this->GetTextRenderObject()->GetCaretRect();
-          scroll_render_object->ScrollToContain(caret_rect, Thickness{5.f});
-        });
+    auto window_host = this->control_->GetWindowHost();
+    if (window_host)
+      window_host->RunAfterLayoutStable([this, scroll_render_object]() {
+        const auto caret_rect = this->GetTextRenderObject()->GetCaretRect();
+        scroll_render_object->ScrollToContain(caret_rect, Thickness{5.f});
+      });
   }
 }
 
@@ -465,8 +467,7 @@ void TextHostControlService::UpdateInputMethodPosition() {
     right_bottom.y += 5;
 
     if constexpr (debug_flags::text_service) {
-      CRU_LOG_DEBUG(
-                    u"Calculate input method candidate window position: {}.",
+      CRU_LOG_DEBUG(u"Calculate input method candidate window position: {}.",
                     right_bottom);
     }
 
@@ -693,7 +694,7 @@ void TextHostControlService::SetUpShortcuts() {
 
 void TextHostControlService::OpenContextMenu(const Point& position,
                                              ContextMenuItem items) {
-  context_menu_ = std::make_unique<components::PopupMenu>();
+  context_menu_ = MakeDeleteLaterPtr<components::PopupMenu>();
   auto menu = context_menu_->GetMenu();
   if (items & ContextMenuItem::kSelectAll) {
     menu->AddTextItem(u"Select All", [this] { this->SelectAll(); });
diff --git a/src/ui/host/RoutedEventDispatch.h b/src/ui/host/RoutedEventDispatch.h
index 2f437b31..5d1c8ce5 100644
--- a/src/ui/host/RoutedEventDispatch.h
+++ b/src/ui/host/RoutedEventDispatch.h
@@ -3,10 +3,11 @@
 #include "cru/common/log/Logger.h"
 #include "cru/ui/DebugFlags.h"
 #include "cru/ui/controls/Control.h"
+#include "cru/ui/host/WindowHost.h"
 
 #include <vector>
 
-namespace cru::ui {
+namespace cru::ui::host {
 // Dispatch the event.
 //
 // This will raise routed event of the control and its parent and parent's
@@ -40,6 +41,8 @@ void DispatchEvent(
     return;
   }
 
+  WindowHost::EnterEventHandling();
+
   std::vector<ObjectResolver<controls::Control>> receive_list;
 
   auto parent = original_sender;
@@ -119,5 +122,7 @@ void DispatchEvent(
 
   if constexpr (debug_flags::routed_event)
     CRU_LOG_DEBUG(u"Routed event dispatch finished.");
+
+  WindowHost::LeaveEventHandling();
 }
-}  // namespace cru::ui
+}  // namespace cru::ui::host
diff --git a/src/ui/host/WindowHost.cpp b/src/ui/host/WindowHost.cpp
index f4a9a928..737a7594 100644
--- a/src/ui/host/WindowHost.cpp
+++ b/src/ui/host/WindowHost.cpp
@@ -7,6 +7,7 @@
 #include "cru/platform/gui/InputMethod.h"
 #include "cru/platform/gui/UiApplication.h"
 #include "cru/platform/gui/Window.h"
+#include "cru/ui/Base.h"
 #include "cru/ui/DebugFlags.h"
 #include "cru/ui/host/LayoutPaintCycler.h"
 #include "cru/ui/render/MeasureRequirement.h"
@@ -105,6 +106,15 @@ inline void BindNativeEvent(
 }
 }  // namespace
 
+int WindowHost::event_handling_depth_ = 0;
+
+void WindowHost::EnterEventHandling() { event_handling_depth_++; }
+
+void WindowHost::LeaveEventHandling() {
+  Expects(event_handling_depth_ > 0);
+  event_handling_depth_--;
+}
+
 WindowHost::WindowHost(controls::Control* root_control)
     : root_control_(root_control), focus_control_(root_control) {
   root_render_object_ = root_control->GetRenderObject();
@@ -438,4 +448,16 @@ void WindowHost::SetOverrideCursor(
   override_cursor_ = cursor;
   UpdateCursor();
 }
+
+void WindowHost::OnControlDetach(controls::Control* control) {
+  if (GetFocusControl() == control) {
+    SetFocusControl(nullptr);
+  }
+  if (GetMouseCaptureControl() == control) {
+    CaptureMouseFor(nullptr);
+  }
+  if (GetMouseHoverControl() == control) {
+    mouse_hover_control_ = HitTest(GetNativeWindow()->GetMousePosition());
+  }
+}
 }  // namespace cru::ui::host