Optimize Windows 10 border handling

Sine Striker

2023-12-25 29901fc2a97eedd3c914f807d1819c9ea7e69973

 src/widgets/widgetwindowagent_win.cpp

@@ -1,9 +1,10 @@
#include "widgetwindowagent_p.h"

#include <QtCore/QDebug>
#include <QtCore/QDateTime>
#include <QtGui/QPainter>

#include <QWKCore/qwindowkit_windows.h>
#include <QWKCore/qwkconfig.h>
#include <QWKCore/private/nativeeventfilter_p.h>

namespace QWK {
@@ -12,26 +13,33 @@

    class WidgetBorderHandler;

    class WidgetBorderHandler : public QObject, public NativeEventFilter {
    class WidgetBorderHandler : public QObject, public NativeEventFilter, public SharedEventFilter {
    public:
        explicit WidgetBorderHandler(QWidget *widget, AbstractWindowContext *ctx)
            : QObject(ctx), widget(widget), ctx(ctx) {
            widget->installEventFilter(this);

            ctx->installNativeEventFilter(this);
            ctx->installSharedEventFilter(this);

            updateGeometry();
        }

        inline bool isNormalWindow() const {
            return !(widget->windowState() &
                     (Qt::WindowMinimized | Qt::WindowMaximized | Qt::WindowFullScreen));
        }

        void updateGeometry() {
            if (widget->windowState() & (Qt::WindowMaximized | Qt::WindowFullScreen)) {
                widget->setContentsMargins({});
            } else {
            if (isNormalWindow()) {
                widget->setContentsMargins({
                    0,
                    ctx->property("borderThickness").toInt(),
                    0,
                    0,
                });
            } else {
                widget->setContentsMargins({});
            }
        }

@@ -61,6 +69,16 @@
                    }
                    break;
                }
#  if 0
                case WM_ACTIVATE: {
                    if (LOWORD(msg->wParam) == WA_INACTIVE) {
                        // 窗口失去激活状态
                    } else {
                        // 窗口被激活
                    }
                    break;
                }
#  endif

                default:
                    break;
@@ -68,35 +86,55 @@
            return false;
        }

        bool sharedEventFilter(QObject *obj, QEvent *event) override {
            Q_UNUSED(obj)

            auto window = widget->windowHandle();
            if (event->type() == QEvent::Expose) {
                // Qt will absolutely send a QExposeEvent to the QWindow when it receives a
                // WM_PAINT message. When the control flow enters the expose handler, Qt must
                // have already called BeginPaint() and it's the best time for us to draw the
                // top border.
                auto ee = static_cast<QExposeEvent *>(event);
                if (isNormalWindow() && window->isExposed() && !ee->region().isNull()) {
                    // Friend class helping to call `event`
                    class HackedWindow : public QWindow {
                    public:
                        friend class QWK::WidgetBorderHandler;
                    };

                    // Let Qt paint first
                    static_cast<HackedWindow *>(window)->event(event);

                    // Upon receiving the WM_PAINT message, Qt will redraw the entire view, and we
                    // must wait for it to finish redrawing before drawing this top border area
                    ctx->virtual_hook(AbstractWindowContext::DrawWindows10BorderHook2, nullptr);
                    return true;
                }
            }
            return false;
        }

        bool eventFilter(QObject *obj, QEvent *event) override {
            Q_UNUSED(obj)
            switch (event->type()) {
                case QEvent::Paint: {
                    if (widget->windowState() &
                        (Qt::WindowMinimized | Qt::WindowMaximized | Qt::WindowFullScreen))
                case QEvent::UpdateRequest: {
                    if (!isNormalWindow())
                        break;

                    // Friend class helping to call `event`
                    class HackedWidget : public QWidget {
                    public:
                        friend class WidgetBorderHandler;
                        friend class QWK::WidgetBorderHandler;
                    };

                    // Let the widget paint first
                    static_cast<HackedWidget *>(widget)->event(event);

                    // Draw border
                    auto paintEvent = static_cast<QPaintEvent *>(event);
                    auto rect = paintEvent->rect();
                    auto region = paintEvent->region();

                    QPainter painter(widget);
                    void *args[] = {
                        &painter,
                        &rect,
                        &region,
                    };
                    ctx->virtual_hook(AbstractWindowContext::DrawWindows10BorderHook, args);
                    // Due to the timer or user action, Qt will redraw some regions spontaneously,
                    // even if there is no WM_PAINT message, we must wait for it to finish redrawing
                    // and then update the upper border area
                    ctx->virtual_hook(AbstractWindowContext::DrawWindows10BorderHook2, nullptr);
                    return true;
                }

@@ -120,16 +158,14 @@
        QWidget *widget;
        AbstractWindowContext *ctx;
    };
#endif

    void WidgetWindowAgentPrivate::setupWindows10BorderWorkaround() {
#if QWINDOWKIT_CONFIG(ENABLE_WINDOWS_SYSTEM_BORDER)
        // Install painting hook
        auto ctx = context.get();
        if (ctx->property("needBorderPainter").toBool()) {
            std::ignore = new WidgetBorderHandler(hostWidget, ctx);
        }
#endif
    }
#endif

}