From da342753a2fb6d6dc8481f952d7dab73b24e2ee4 Mon Sep 17 00:00:00 2001
From: Altair Wei <altair_wei@outlook.com>
Date: Sun, 19 Sep 2021 17:47:14 +0800
Subject: [PATCH] change cursor according mouse state

---
 framelesshelper.cpp | 65 +++++++++++++++++++++++++++++++++++++++++++++
 framelesshelper.h   |  9 +++++++
 2 files changed, 74 insertions(+)

diff --git a/framelesshelper.cpp b/framelesshelper.cpp
index 17f5e62..34fa01a 100644
--- a/framelesshelper.cpp
+++ b/framelesshelper.cpp
@@ -157,6 +157,71 @@ Qt::WindowFrameSection FramelessHelper::mapPosToFrameSection(const QPoint& pos)
     return Qt::NoSection;
 }
 
+bool FramelessHelper::isHoverResizeHandler()
+{
+    return m_hoveredFrameSection == Qt::LeftSection ||
+        m_hoveredFrameSection == Qt::RightSection ||
+        m_hoveredFrameSection == Qt::TopSection ||
+        m_hoveredFrameSection == Qt::BottomSection ||
+        m_hoveredFrameSection == Qt::TopLeftSection ||
+        m_hoveredFrameSection == Qt::TopRightSection ||
+        m_hoveredFrameSection == Qt::BottomLeftSection ||
+        m_hoveredFrameSection == Qt::BottomRightSection;
+}
+
+QCursor FramelessHelper::cursorForFrameSection(Qt::WindowFrameSection frameSection)
+{
+    Qt::CursorShape cursor = Qt::ArrowCursor;
+
+    switch (frameSection)
+    {
+    case Qt::LeftSection:
+    case Qt::RightSection:
+        cursor = Qt::SizeHorCursor;
+        break;
+    case Qt::BottomSection:
+    case Qt::TopSection:
+        cursor = Qt::SizeVerCursor;
+        break;
+    case Qt::TopLeftSection:
+    case Qt::BottomRightSection:
+        cursor = Qt::SizeFDiagCursor;
+        break;
+    case Qt::TopRightSection:
+    case Qt::BottomLeftSection:
+        cursor = Qt::SizeBDiagCursor;
+        break;
+    case Qt::TitleBarArea:
+        cursor = Qt::ArrowCursor;
+        break;
+    default:
+        break;
+    }
+
+    return QCursor(cursor);
+}
+
+void FramelessHelper::setCursor(const QCursor& cursor)
+{
+    m_window->setCursor(cursor);
+    m_cursorChanged = true;
+}
+
+void FramelessHelper::unsetCursor()
+{
+    if (!m_cursorChanged)
+        return;
+
+    m_window->unsetCursor();
+    m_cursorChanged = false;
+}
+
+void FramelessHelper::updateCursor()
+{
+    if (isHoverResizeHandler())
+        setCursor(cursorForFrameSection(m_hoveredFrameSection));
+}
+
 bool FramelessHelper::eventFilter(QObject *object, QEvent *event)
 {
 
diff --git a/framelesshelper.h b/framelesshelper.h
index 62904fb..12d4bfd 100644
--- a/framelesshelper.h
+++ b/framelesshelper.h
@@ -70,6 +70,13 @@ public:
     bool isInTitlebarArea(const QPoint& pos);
     Qt::WindowFrameSection mapPosToFrameSection(const QPoint& pos);
 
+    bool isHoverResizeHandler();
+
+    QCursor cursorForFrameSection(Qt::WindowFrameSection frameSection);
+    void setCursor(const QCursor& cursor);
+    void unsetCursor();
+    void updateCursor();
+
 protected:
     bool eventFilter(QObject *object, QEvent *event) override;
 
@@ -80,6 +87,8 @@ private:
     int m_resizeBorderThickness;
     bool m_resizable;
     Qt::WindowFlags m_origWindowFlags;
+    bool m_cursorChanged;
+    Qt::WindowFrameSection m_hoveredFrameSection;
 };
 
 FRAMELESSHELPER_END_NAMESPACE