[重构图形项鼠标事件处理并优化字幕分割线功能]：统一了各图形项的鼠标事件处理机制，新增专用字幕分割线组件，并优化了边缘检测算法

-**图形项鼠标事件重构**: 将原有各图形项（圆弧、圆、线、多边形、圆环、旋转矩形、圆角矩形）中的鼠标移动和悬停事件处理逻辑统一抽象到基类`GraphicsBasicItem`中，通过新增`handleMouseMoveEvent`、`detectEdgeRegion`和`updateHoverPreview`等虚函数实现差异化处理，提高代码复用性和可维护性
-**新增字幕分割线组件**: 删除原有`CustomLineItem`类，新增`SubtitleDividerLineItem`专用组件，重写鼠标移动事件处理逻辑，确保分割线仅支持垂直方向移动，优化字幕拼接界面交互体验
-**图形项边缘检测优化**: 在各图形项中实现`detectEdgeRegion`方法，改进边缘区域检测算法，使用`Utils::isPointNearEdge`方法替代原有粗略计算，提升边缘拖拽操作的精准度
-**示例代码同步更新**: 同步更新示例代码中相关组件引用，将`SectionalSubtitlesView`中的分割线组件替换为新的`SubtitleDividerLineItem`，并修复分割线位置计算逻辑
-**图形工具函数增强**: 在`graphicsutils`中新增`isPointNearEdge`和`pointAtDistance`工具函数，提供更精确的点到边缘距离计算和坐标点定位功能
-**视图初始化优化**: 提取`GraphicsView`初始化逻辑到独立方法`initializeView`中，改善代码结构清晰度
-**条件判断简化**: 在`subtitlsplicingwidget.cc`中简化信号处理函数的条件判断逻辑，提升代码可读性
-**Lambda表达式安全优化**: 在`listiitemview.cc`中修正lambda表达式捕获方式，避免潜在的空指针访问问题

Author: RealChuan

examples/graphics/CMakeLists.txt

@@ -9,8 +9,6 @@ set(PROJECT_SOURCES
     ../common/viewer.hpp
     capturewidget.cc
     capturewidget.hpp
-    customlineitem.cc
-    customlineitem.hpp
     drawscene.cc
     drawscene.hpp
     drawwidget.cpp
@@ -46,6 +44,8 @@ set(PROJECT_SOURCES
     sizeselectorwidget.hpp
     stretchparamssettingdailog.cc
     stretchparamssettingdailog.hpp
+    subtitledividerlineitem.cc
+    subtitledividerlineitem.hpp
     subtitlsplicingwidget.cc
     subtitlsplicingwidget.hpp)
 

examples/graphics/customlineitem.cc

@@ -23,7 +23,6 @@ SOURCES += \
     ../common/thumbnail.cc \
     ../common/imagelistmodel.cpp \
     capturewidget.cc \
-    customlineitem.cc \
     drawscene.cc \
     drawwidget.cpp \
     icoconverterwidget.cc \
@@ -42,6 +41,7 @@ SOURCES += \
     selectionwidget.cc \
     sizeselectorwidget.cc \
     stretchparamssettingdailog.cc \
+    subtitledividerlineitem.cc \
     subtitlsplicingwidget.cc
 
 HEADERS += \
@@ -50,7 +50,6 @@ HEADERS += \
     ../common/thumbnail.hpp \
     ../common/imagelistmodel.h \
     capturewidget.hpp \
-    customlineitem.hpp \
     drawscene.hpp \
     drawwidget.h \
     icoconverterwidget.hpp \
@@ -68,6 +67,7 @@ HEADERS += \
     selectionwidget.hpp \
     sizeselectorwidget.hpp \
     stretchparamssettingdailog.hpp \
+    subtitledividerlineitem.hpp \
     subtitlsplicingwidget.hpp
 
 win32 {

examples/graphics/customlineitem.hpp

@@ -22,9 +22,10 @@ class LoadImageTask : public QRunnable
         auto widgetSize = m_viewPtr->size();
         auto imageSize = image.size();
         image = image.scaled(widgetSize, Qt::KeepAspectRatio /*, Qt::SmoothTransformation*/);
+        auto view = m_viewPtr.data();
         QMetaObject::invokeMethod(
-            m_viewPtr.data(),
-            [this, image, imageSize] { m_viewPtr->setImage(image, imageSize); },
+            view,
+            [view, image, imageSize] { view->setImage(image, imageSize); },
             Qt::QueuedConnection);
     }
 

examples/graphics/graphics.pro

@@ -1,5 +1,5 @@
 #include "sectionalsubtitlesview.hpp"
-#include "customlineitem.hpp"
+#include "subtitledividerlineitem.hpp"
 
 #include <QtWidgets>
 
@@ -8,14 +8,14 @@ class SectionalSubtitlesView::SectionalSubtitlesViewPrivate
 public:
     SectionalSubtitlesViewPrivate(QWidget *parent)
         : q_ptr(parent)
-        , line1Ptr(new CustomLineItem)
-        , line2Ptr(new CustomLineItem)
+        , line1Ptr(new SubtitleDividerLineItem)
+        , line2Ptr(new SubtitleDividerLineItem)
     {}
     ~SectionalSubtitlesViewPrivate() {}
 
     QWidget *q_ptr;
-    QScopedPointer<CustomLineItem> line1Ptr;
-    QScopedPointer<CustomLineItem> line2Ptr;
+    SubtitleDividerLineItemPtr line1Ptr;
+    SubtitleDividerLineItemPtr line2Ptr;
 };
 
 SectionalSubtitlesView::SectionalSubtitlesView(QWidget *parent)
@@ -31,10 +31,10 @@ void SectionalSubtitlesView::setImageAfter()
 {
     auto rect = sceneRect();
     auto y = rect.height() / 5.0 * 4;
-    d_ptr->line1Ptr->setLine(QLineF(1, y, rect.width() - 1, y));
-    d_ptr->line2Ptr->setLine(QLineF(1, rect.height() - 2, rect.width() - 1, rect.height() - 2));
     scene()->addItem(d_ptr->line1Ptr.data());
     scene()->addItem(d_ptr->line2Ptr.data());
+    d_ptr->line1Ptr->setLine(QLineF(1, y, rect.width() - 1, y));
+    d_ptr->line2Ptr->setLine(QLineF(1, rect.height() - 1, rect.width() - 1, rect.height() - 1));
 }
 
 auto SectionalSubtitlesView::clipImage() const -> QImage
@@ -64,7 +64,7 @@ auto SectionalSubtitlesView::info() const -> StitchingImageInfo
 
 auto SectionalSubtitlesView::line1RatioOfHeight() const -> double
 {
-    return (d_ptr->line1Ptr->line().y1() / pixmap().size().height());
+    return (static_cast<int>(d_ptr->line1Ptr->line().y1()) * 1.0 / pixmap().size().height());
 }
 
 void SectionalSubtitlesView::setLine1RatioOfHeight(double value)
@@ -76,7 +76,7 @@ void SectionalSubtitlesView::setLine1RatioOfHeight(double value)
 
 auto SectionalSubtitlesView::line2RatioOfHeight() const -> double
 {
-    return (d_ptr->line2Ptr->line().y1() / pixmap().size().height());
+    return (static_cast<int>(d_ptr->line2Ptr->line().y1()) * 1.0 / pixmap().size().height());
 }
 
 void SectionalSubtitlesView::setLine2RatioOfHeight(double value)
@@ -89,11 +89,11 @@ void SectionalSubtitlesView::setLine2RatioOfHeight(double value)
 void SectionalSubtitlesView::buildConnect()
 {
     connect(d_ptr->line1Ptr.data(),
-            &CustomLineItem::lineChanged,
+            &SubtitleDividerLineItem::lineChanged,
             this,
             &SectionalSubtitlesView::line1Changed);
     connect(d_ptr->line2Ptr.data(),
-            &CustomLineItem::lineChanged,
+            &SubtitleDividerLineItem::lineChanged,
             this,
             &SectionalSubtitlesView::line2Changed);
 }

examples/graphics/listiitemview.cc

@@ -0,0 +1,25 @@
+#include "subtitledividerlineitem.hpp"
+
+#include <graphics/geometrycache.hpp>
+
+SubtitleDividerLineItem::SubtitleDividerLineItem(QGraphicsItem *parent)
+    : GraphicsLineItem(parent)
+{
+    setMargin(0.5);
+    setShowBoundingRect(false);
+    setShowShape(false);
+}
+
+void SubtitleDividerLineItem::handleMouseMoveEvent(const QPointF &scenePos,
+                                                   const QPointF &clickedPos,
+                                                   const QPointF delta)
+{
+    auto dp = QPointF(0, delta.y());
+    auto controlPoints = geometryCache()->controlPoints();
+
+    switch (mouseRegion()) {
+    case MouseRegion::EntireShape: controlPoints.translate(dp); break;
+    default: return;
+    }
+    pointsChanged(controlPoints);
+}

examples/graphics/sectionalsubtitlesview.cc

@@ -0,0 +1,16 @@
+#pragma once
+
+#include <graphics/graphicslineitem.h>
+
+class SubtitleDividerLineItem : public Graphics::GraphicsLineItem
+{
+public:
+    explicit SubtitleDividerLineItem(QGraphicsItem *parent = nullptr);
+
+protected:
+    void handleMouseMoveEvent(const QPointF &scenePos,
+                              const QPointF &clickedPos,
+                              const QPointF delta) override;
+};
+
+using SubtitleDividerLineItemPtr = QScopedPointer<SubtitleDividerLineItem>;

examples/graphics/subtitledividerlineitem.cc

@@ -216,28 +216,22 @@ void SubtitlSplicingWidget::onDown(int index)
 void SubtitlSplicingWidget::onLine1Changed()
 {
     auto *view = qobject_cast<SectionalSubtitlesView *>(sender());
-    if (!view) {
-        return;
-    }
-    if (view->index() != 0) {
+    if (!view || view->index() != 0) {
         return;
     }
 
     auto radoi = view->line1RatioOfHeight();
     for (int i = 1; i < d_ptr->listWidget->count(); i++) {
-        auto item = d_ptr->listWidget->item(i);
-        auto view = qobject_cast<SectionalSubtitlesView *>(d_ptr->listWidget->itemWidget(item));
+        auto *item = d_ptr->listWidget->item(i);
+        auto *view = qobject_cast<SectionalSubtitlesView *>(d_ptr->listWidget->itemWidget(item));
         view->setLine1RatioOfHeight(radoi);
     }
 }
 
 void SubtitlSplicingWidget::onLine2Changed()
 {
     auto *view = qobject_cast<SectionalSubtitlesView *>(sender());
-    if (!view) {
-        return;
-    }
-    if (view->index() != 0) {
+    if (!view || view->index() != 0) {
         return;
     }