Return correct hit-test values for title bar buttons on Windows (#4994)

Co-authored-by: Rasmus Karlsson <rasmus.karlsson@pajlada.com>

CHANGELOG.md

@@ -43,6 +43,7 @@
 - Bugfix: Fixed lookahead/-behind not working in _Ignores_. (#4965)
 - Bugfix: Fixed Image Uploader accidentally deleting images with some hosts when link resolver was enabled. (#4971)
 - Bugfix: Fixed rare crash with Image Uploader when closing a split right after starting an upload. (#4971)
+- Bugfix: Fixed support for Windows 11 Snap layouts. (#4994)
 - Bugfix: Fixed some windows appearing between screens. (#4797)
 - Dev: Run miniaudio in a separate thread, and simplify it to not manage the device ourselves. There's a chance the simplification is a bad idea. (#4978)
 - Dev: Change clang-format from v14 to v16. (#4929)

src/CMakeLists.txt

@@ -626,6 +626,8 @@ set(SOURCE_FILES
         widgets/helper/SignalLabel.hpp
         widgets/helper/TitlebarButton.cpp
         widgets/helper/TitlebarButton.hpp
+        widgets/helper/TitlebarButtons.cpp
+        widgets/helper/TitlebarButtons.hpp
 
         widgets/listview/GenericItemDelegate.cpp
         widgets/listview/GenericItemDelegate.hpp

src/widgets/BaseWindow.cpp

@@ -8,6 +8,7 @@
 #include "util/PostToThread.hpp"
 #include "util/WindowsHelper.hpp"
 #include "widgets/helper/EffectLabel.hpp"
+#include "widgets/helper/TitlebarButtons.hpp"
 #include "widgets/Label.hpp"
 #include "widgets/TooltipWidget.hpp"
 #include "widgets/Window.hpp"
@@ -180,9 +181,8 @@ void BaseWindow::init()
                                      this->close();
                                  });
 
-                this->ui_.minButton = _minButton;
+                this->ui_.titlebarButtons = new TitleBarButtons(
-                this->ui_.maxButton = _maxButton;
+                    this, _minButton, _maxButton, _exitButton);
-                this->ui_.exitButton = _exitButton;
 
                 this->ui_.buttons.push_back(_minButton);
                 this->ui_.buttons.push_back(_maxButton);
@@ -474,12 +474,9 @@ void BaseWindow::changeEvent(QEvent *)
     }
 
 #ifdef USEWINSDK
-    if (this->ui_.maxButton)
+    if (this->ui_.titlebarButtons)
     {
-        this->ui_.maxButton->setButtonStyle(
+        this->ui_.titlebarButtons->updateMaxButton();
-            this->windowState() & Qt::WindowMaximized
-                ? TitleBarButtonStyle::Unmaximize
-                : TitleBarButtonStyle::Maximize);
     }
 
     if (this->isVisible() && this->hasCustomWindowFrame())
@@ -585,6 +582,11 @@ bool BaseWindow::nativeEvent(const QByteArray &eventType, void *message,
 
     bool returnValue = false;
 
+    auto isHoveringTitlebarButton = [&]() {
+        auto ht = msg->wParam;
+        return ht == HTMAXBUTTON || ht == HTMINBUTTON || ht == HTCLOSE;
+    };
+
     switch (msg->message)
     {
         case WM_DPICHANGED:
@@ -612,6 +614,91 @@ bool BaseWindow::nativeEvent(const QByteArray &eventType, void *message,
             returnValue = this->handleNCHITTEST(msg, result);
             break;
 
+        case WM_NCMOUSEHOVER:
+        case WM_NCMOUSEMOVE: {
+            // WM_NCMOUSEMOVE/WM_NCMOUSEHOVER gets sent when the mouse is
+            // moving/hovering in the non-client area
+            // - (mostly) the edges and the titlebar.
+            // We only need to handle the event for the titlebar buttons,
+            // as Qt doesn't create mouse events for these events.
+            if (!this->ui_.titlebarButtons)
+            {
+                // we don't consume the event if we don't have custom buttons
+                break;
+            }
+
+            if (isHoveringTitlebarButton())
+            {
+                *result = 0;
+                returnValue = true;
+                long x = GET_X_LPARAM(msg->lParam);
+                long y = GET_Y_LPARAM(msg->lParam);
+
+                RECT winrect;
+                GetWindowRect(HWND(winId()), &winrect);
+                QPoint globalPos(x, y);
+                this->ui_.titlebarButtons->hover(msg->wParam, globalPos);
+                this->lastEventWasNcMouseMove_ = true;
+            }
+            else
+            {
+                this->ui_.titlebarButtons->leave();
+            }
+        }
+        break;
+
+        case WM_MOUSEMOVE: {
+            if (!this->lastEventWasNcMouseMove_)
+            {
+                break;
+            }
+            this->lastEventWasNcMouseMove_ = false;
+            // Windows doesn't send WM_NCMOUSELEAVE in some cases,
+            // so the buttons show as hovered even though they're not hovered.
+            [[fallthrough]];
+        }
+        case WM_NCMOUSELEAVE: {
+            // WM_NCMOUSELEAVE gets sent when the mouse leaves any
+            // non-client area. In case we have titlebar buttons,
+            // we want to ensure they're deselected.
+            if (this->ui_.titlebarButtons)
+            {
+                this->ui_.titlebarButtons->leave();
+            }
+        }
+        break;
+
+        case WM_NCLBUTTONDOWN:
+        case WM_NCLBUTTONUP: {
+            // WM_NCLBUTTON{DOWN, UP} gets called when the left mouse button
+            // was pressed in a non-client area.
+            // We simulate a mouse down/up event for the titlebar buttons
+            // as Qt doesn't create an event in that case.
+            if (!this->ui_.titlebarButtons || !isHoveringTitlebarButton())
+            {
+                break;
+            }
+            returnValue = true;
+            *result = 0;
+
+            auto ht = msg->wParam;
+            long x = GET_X_LPARAM(msg->lParam);
+            long y = GET_Y_LPARAM(msg->lParam);
+
+            RECT winrect;
+            GetWindowRect(HWND(winId()), &winrect);
+            QPoint globalPos(x, y);
+            if (msg->message == WM_NCLBUTTONDOWN)
+            {
+                this->ui_.titlebarButtons->mousePress(ht, globalPos);
+            }
+            else
+            {
+                this->ui_.titlebarButtons->mouseRelease(ht, globalPos);
+            }
+        }
+        break;
+
         default:
             return QWidget::nativeEvent(eventType, message, result);
     }
@@ -668,29 +755,21 @@ void BaseWindow::calcButtonsSizes()
         return;
     }
 
-    if (this->frameless_)
+    if (this->frameless_ || !this->ui_.titlebarButtons)
     {
         return;
     }
 
-    if ((this->width() / this->scale()) < 300)
+#ifdef USEWINSDK
+    if ((static_cast<float>(this->width()) / this->scale()) < 300)
     {
-        if (this->ui_.minButton)
+        this->ui_.titlebarButtons->setSmallSize();
-            this->ui_.minButton->setScaleIndependantSize(30, 30);
-        if (this->ui_.maxButton)
-            this->ui_.maxButton->setScaleIndependantSize(30, 30);
-        if (this->ui_.exitButton)
-            this->ui_.exitButton->setScaleIndependantSize(30, 30);
     }
     else
     {
-        if (this->ui_.minButton)
+        this->ui_.titlebarButtons->setRegularSize();
-            this->ui_.minButton->setScaleIndependantSize(46, 30);
-        if (this->ui_.maxButton)
-            this->ui_.maxButton->setScaleIndependantSize(46, 30);
-        if (this->ui_.exitButton)
-            this->ui_.exitButton->setScaleIndependantSize(46, 30);
     }
+#endif
 }
 
 void BaseWindow::drawCustomWindowFrame(QPainter &painter)
@@ -943,32 +1022,55 @@ bool BaseWindow::handleNCHITTEST(MSG *msg, long *result)
 
         if (*result == 0)
         {
-            bool client = false;
-
             // Check the main layout first, as it's the largest area
             if (this->ui_.layoutBase->geometry().contains(point))
             {
-                client = true;
+                *result = HTCLIENT;
             }
 
             // Check the titlebar buttons
-            if (!client && this->ui_.titlebarBox->geometry().contains(point))
+            if (*result == 0 &&
+                this->ui_.titlebarBox->geometry().contains(point))
             {
-                for (QWidget *widget : this->ui_.buttons)
+                for (const auto *widget : this->ui_.buttons)
                 {
-                    if (widget->isVisible() &&
+                    if (!widget->isVisible() ||
-                        widget->geometry().contains(point))
+                        !widget->geometry().contains(point))
                     {
-                        client = true;
+                        continue;
                     }
+
+                    if (const auto *btn =
+                            dynamic_cast<const TitleBarButton *>(widget))
+                    {
+                        switch (btn->getButtonStyle())
+                        {
+                            case TitleBarButtonStyle::Minimize: {
+                                *result = HTMINBUTTON;
+                                break;
+                            }
+                            case TitleBarButtonStyle::Unmaximize:
+                            case TitleBarButtonStyle::Maximize: {
+                                *result = HTMAXBUTTON;
+                                break;
+                            }
+                            case TitleBarButtonStyle::Close: {
+                                *result = HTCLOSE;
+                                break;
+                            }
+                            default: {
+                                *result = HTCLIENT;
+                                break;
+                            }
+                        }
+                        break;
+                    }
+                    *result = HTCLIENT;
+                    break;
                 }
             }
 
-            if (client)
+            if (*result == 0)
-            {
-                *result = HTCLIENT;
-            }
-            else
             {
                 *result = HTCAPTION;
             }

src/widgets/BaseWindow.hpp

@@ -18,6 +18,7 @@ namespace chatterino {
 class Button;
 class EffectLabel;
 class TitleBarButton;
+class TitleBarButtons;
 enum class TitleBarButtonStyle;
 
 class BaseWindow : public BaseWidget
@@ -135,9 +136,7 @@ private:
         QLayout *windowLayout = nullptr;
         QHBoxLayout *titlebarBox = nullptr;
         QWidget *titleLabel = nullptr;
-        TitleBarButton *minButton = nullptr;
+        TitleBarButtons *titlebarButtons = nullptr;
-        TitleBarButton *maxButton = nullptr;
-        TitleBarButton *exitButton = nullptr;
         QWidget *layoutBase = nullptr;
         std::vector<Button *> buttons;
     } ui_;
@@ -148,6 +147,7 @@ private:
     QRect nextBounds_;
     QTimer useNextBounds_;
     bool isNotMinimizedOrMaximized_{};
+    bool lastEventWasNcMouseMove_ = false;
 #endif
 
     pajlada::Signals::SignalHolder connections_;

src/widgets/helper/TitlebarButton.cpp

@@ -124,4 +124,39 @@ void TitleBarButton::paintEvent(QPaintEvent *event)
     this->paintButton(painter);
 }
 
+void TitleBarButton::ncEnter()
+{
+    this->enterEvent(nullptr);
+    this->update();
+}
+
+void TitleBarButton::ncLeave()
+{
+    this->leaveEvent(nullptr);
+    this->update();
+}
+
+void TitleBarButton::ncMove(QPoint at)
+{
+    QMouseEvent evt(QMouseEvent::MouseMove, at, Qt::NoButton, Qt::NoButton,
+                    Qt::NoModifier);
+    this->mouseMoveEvent(&evt);
+}
+
+void TitleBarButton::ncMousePress(QPoint at)
+{
+    QMouseEvent evt(QMouseEvent::MouseButtonPress, at, Qt::LeftButton,
+                    Qt::NoButton, Qt::NoModifier);
+    this->mousePressEvent(&evt);
+    this->update();
+}
+
+void TitleBarButton::ncMouseRelease(QPoint at)
+{
+    QMouseEvent evt(QMouseEvent::MouseButtonRelease, at, Qt::LeftButton,
+                    Qt::NoButton, Qt::NoModifier);
+    this->mouseReleaseEvent(&evt);
+    this->update();
+}
+
 }  // namespace chatterino

src/widgets/helper/TitlebarButton.hpp

@@ -23,6 +23,24 @@ public:
     TitleBarButtonStyle getButtonStyle() const;
     void setButtonStyle(TitleBarButtonStyle style_);
 
+    /// Simulate a `mouseEnter` event.
+    void ncEnter();
+
+    /// Simulate a `mouseLeave` event.
+    void ncLeave();
+
+    /// Simulate a `mouseMove` event.
+    /// @param at a local position relative to this widget
+    void ncMove(QPoint at);
+
+    /// Simulate a `mousePress` event with the left mouse button.
+    /// @param at a local position relative to this widget
+    void ncMousePress(QPoint at);
+
+    /// Simulate a `mouseRelease` event with the left mouse button.
+    /// @param at a local position relative to this widget
+    void ncMouseRelease(QPoint at);
+
 protected:
     void paintEvent(QPaintEvent *) override;
 

src/widgets/helper/TitlebarButtons.cpp

@@ -0,0 +1,116 @@
+#include "widgets/helper/TitlebarButtons.hpp"
+
+#ifdef USEWINSDK
+
+#    include "widgets/helper/TitlebarButton.hpp"
+
+#    include <Windows.h>
+
+#    include <cassert>
+
+namespace chatterino {
+
+TitleBarButtons::TitleBarButtons(QWidget *window, TitleBarButton *minButton,
+                                 TitleBarButton *maxButton,
+                                 TitleBarButton *closeButton)
+    : QObject(window)
+    , window_(window)
+    , minButton_(minButton)
+    , maxButton_(maxButton)
+    , closeButton_(closeButton)
+{
+}
+
+void TitleBarButtons::hover(size_t ht, QPoint at)
+{
+    TitleBarButton *hovered{};
+    TitleBarButton *other1{};
+    TitleBarButton *other2{};
+    switch (ht)
+    {
+        case HTMAXBUTTON:
+            hovered = this->maxButton_;
+            other1 = this->minButton_;
+            other2 = this->closeButton_;
+            break;
+        case HTMINBUTTON:
+            hovered = this->minButton_;
+            other1 = this->maxButton_;
+            other2 = this->closeButton_;
+            break;
+        case HTCLOSE:
+            hovered = this->closeButton_;
+            other1 = this->minButton_;
+            other2 = this->maxButton_;
+            break;
+        default:
+            assert(false && "TitleBarButtons::hover precondition violated");
+            return;
+    }
+    hovered->ncEnter();
+    hovered->ncMove(hovered->mapFromGlobal(at));
+    other1->ncLeave();
+    other2->ncLeave();
+}
+
+void TitleBarButtons::leave()
+{
+    this->minButton_->ncLeave();
+    this->maxButton_->ncLeave();
+    this->closeButton_->ncLeave();
+}
+
+void TitleBarButtons::mousePress(size_t ht, QPoint at)
+{
+    auto *button = this->buttonForHt(ht);
+    button->ncMousePress(button->mapFromGlobal(at));
+}
+
+void TitleBarButtons::mouseRelease(size_t ht, QPoint at)
+{
+    auto *button = this->buttonForHt(ht);
+    button->ncMouseRelease(button->mapFromGlobal(at));
+}
+
+void TitleBarButtons::updateMaxButton()
+{
+    this->maxButton_->setButtonStyle(
+        this->window_->windowState().testFlag(Qt::WindowMaximized)
+            ? TitleBarButtonStyle::Unmaximize
+            : TitleBarButtonStyle::Maximize);
+}
+
+void TitleBarButtons::setSmallSize()
+{
+    this->minButton_->setScaleIndependantSize(30, 30);
+    this->maxButton_->setScaleIndependantSize(30, 30);
+    this->closeButton_->setScaleIndependantSize(30, 30);
+}
+
+void TitleBarButtons::setRegularSize()
+{
+    this->minButton_->setScaleIndependantSize(46, 30);
+    this->maxButton_->setScaleIndependantSize(46, 30);
+    this->closeButton_->setScaleIndependantSize(46, 30);
+}
+
+TitleBarButton *TitleBarButtons::buttonForHt(size_t ht) const
+{
+    switch (ht)
+    {
+        case HTMAXBUTTON:
+            return this->maxButton_;
+        case HTMINBUTTON:
+            return this->minButton_;
+        case HTCLOSE:
+            return this->closeButton_;
+        default:
+            assert(false &&
+                   "TitleBarButtons::buttonForHt precondition violated");
+            return nullptr;
+    }
+}
+
+}  // namespace chatterino
+
+#endif

src/widgets/helper/TitlebarButtons.hpp

@@ -0,0 +1,69 @@
+#pragma once
+
+class QPoint;
+class QWidget;
+
+#include <QtGlobal>
+
+namespace chatterino {
+
+#ifdef USEWINSDK
+
+class TitleBarButton;
+class TitleBarButtons : QObject
+{
+public:
+    /// The parent of this object is set to `window`.
+    ///
+    /// All parameters must have a parent;
+    /// they're not deleted in the destructor.
+    TitleBarButtons(QWidget *window, TitleBarButton *minButton,
+                    TitleBarButton *maxButton, TitleBarButton *closeButton);
+
+    /// Hover over the button `ht` at the global position `at`.
+    ///
+    /// @pre `ht` must be one of { HTMAXBUTTON, HTMINBUTTON, HTCLOSE }.
+    /// @param ht The hovered button
+    /// @param at The global position of the event
+    void hover(size_t ht, QPoint at);
+
+    /// Leave all buttons - simulate `leaveEvent` for all buttons.
+    void leave();
+
+    /// Press the left mouse over the button `ht` at the global position `at`.
+    ///
+    /// @pre `ht` must be one of { HTMAXBUTTON, HTMINBUTTON, HTCLOSE }.
+    /// @param ht The clicked button
+    /// @param at The global position of the event
+    void mousePress(size_t ht, QPoint at);
+
+    /// Release the left mouse button over the button `ht` at the
+    /// global position `at`.
+    ///
+    /// @pre `ht` must be one of { HTMAXBUTTON, HTMINBUTTON, HTCLOSE }.
+    /// @param ht The clicked button
+    /// @param at The global position of the event
+    void mouseRelease(size_t ht, QPoint at);
+
+    /// Update the maximize/restore button to show the correct image
+    /// according to the current window state.
+    void updateMaxButton();
+
+    /// Set buttons to be narrow.
+    void setSmallSize();
+    /// Set buttons to be regular size.
+    void setRegularSize();
+
+private:
+    /// @pre ht must be one of { HTMAXBUTTON, HTMINBUTTON, HTCLOSE }.
+    TitleBarButton *buttonForHt(size_t ht) const;
+
+    QWidget *window_ = nullptr;
+    TitleBarButton *minButton_ = nullptr;
+    TitleBarButton *maxButton_ = nullptr;
+    TitleBarButton *closeButton_ = nullptr;
+};
+
+#endif
+
+}  // namespace chatterino