feat: v0.3.0 —— 默认编辑模式就地渲染，侧栏自动刷新

编辑模式 / 源代码模式语义修正
- 默认「编辑模式」不再显示 #、**、反引号等标记：标题按级别放大加粗、
  粗体真加粗、行内代码带底色、链接只保留文字
- 光标所在行会露出原始标记，方便直接修改；切换行时只重排这两行
- 源代码模式仍是原样显示 + 着色，左下角 <src> 切换

高亮器
- QSyntaxHighlighter::setFormat 是整段替换而非合并，改为每段先与
  当前行基础格式（标题 / 引用 / 代码块）compose 后再设置
- 强调正则收紧，避免 **粗体** 被 *斜体* 抢先匹配

侧栏
- 去掉刷新按钮，改为每 5 秒自动扫描；文件集合没变就不重建列表
- 状态栏左下角新增「侧栏」开关按钮，与 Ctrl+B 同步

其它
- 使用 logo.png 作为窗口图标（resources.qrc）
- 版本号 0.3.0，README 同步更新

README.md

@@ -2,7 +2,7 @@
 
 一个轻量的跨平台 Markdown 编辑器，基于 **Qt 5 / C++17** 构建。
 
-当前版本 **0.2.0**。
+当前版本 **0.3.0**。
 
 ## 界面
 
@@ -20,6 +20,7 @@
   链接与图片、引用、有序 / 无序列表、任务列表、分隔线
 - `Ctrl+1` ~ `Ctrl+6` 把选中行设成 1–6 级标题，再按一次变回正文
 - `Ctrl+/` 把选中内容包成围栏代码块，再按一次拆掉
+- 默认「编辑模式」隐藏 Markdown 标记、标题按级别放大，光标所在行露出原始标记
 - 行号栏、当前行高亮
 - `Tab` / `Shift+Tab` 整行缩进，选中多行时批量缩进
 - 自动换行（`Alt+Z`）、`Ctrl+滚轮` 或 `Ctrl++` / `Ctrl+-` 缩放字号
@@ -30,15 +31,19 @@
 
 - **文件 → 打开文件夹…**（`Ctrl+Shift+O`）选一个目录，递归扫描
   `*.md` / `*.markdown` / `*.mdown` / `*.mkd`
-- `Ctrl+B` 显示 / 隐藏侧栏
-- 点文件名即打开，当前文件在列表里高亮；右上角「刷新」重新扫描
+- 状态栏左下角的「侧栏」按钮或 `Ctrl+B` 显示 / 隐藏
+- 点文件名即打开，当前文件在列表里高亮
+- 每 5 秒自动扫描一次：目录里新增 / 删除的 Markdown 会自动出现在列表里
 - 上次打开的文件夹会被记住，下次启动自动恢复
 
-### 源代码模式
+### 编辑模式 / 源代码模式
 
-左下角状态栏的 **`<src>`** 按钮（或 `Ctrl+Shift+M`）切到源代码模式：
-关掉语法高亮、行号与当前行高亮，只显示文件原始内容，适合核对格式或复制纯文本。
-默认是编辑模式，按钮会显示成 `</src>` 表示当前处于源码模式。
+默认是**编辑模式**：Markdown 标记不显示——标题按级别放大加粗、粗体真加粗、
+行内代码带底色、链接只留文字，看到的就是排版后的内容。光标移到哪一行，
+那一行会露出 `#`、`**` 这些原始标记，可以直接修改。
+
+点左下角的 **`<src>`**（或 `Ctrl+Shift+M`）切到**源代码模式**：所有标记原样显示，
+只做着色，适合核对格式或复制纯文本；按钮会变成 `</src>`。
 
 ### 文件
 

VoiletMark.pro

@@ -1,16 +1,18 @@
 TEMPLATE = app
 TARGET   = VoiletMark
-VERSION  = 0.2.0
+VERSION  = 0.3.0
 
 QT += core gui widgets
 
 CONFIG += c++17 warn_on
 
-# 让 main.cpp 里的 QStringLiteral(VM_VERSION) 拿到 "0.1.0"
+# 让 main.cpp 里的 QStringLiteral(VM_VERSION) 拿到版本号字符串
 DEFINES += VM_VERSION=\\\"$$VERSION\\\"
 
 INCLUDEPATH += $$PWD/src
 
+RESOURCES += resources.qrc
+
 SOURCES += \
     src/main.cpp \
     src/MainWindow.cpp \

resources.qrc

@@ -0,0 +1,5 @@
+<RCC>
+    <qresource prefix="/">
+        <file>logo.png</file>
+    </qresource>
+</RCC>

src/MainWindow.cpp

@@ -193,6 +193,10 @@ void MainWindow::createActions()
     connect(m_sidebarAction, &QAction::toggled, this, [this](bool visible) {
         if (m_sidebar)
             m_sidebar->setVisible(visible);
+        if (m_sidebarButton) {
+            const QSignalBlocker blocker(m_sidebarButton);
+            m_sidebarButton->setChecked(visible);
+        }
         QSettings().setValue(QStringLiteral("window/sidebarVisible"), visible);
     });
 
@@ -230,16 +234,9 @@ void MainWindow::createSidebar()
     layout->setContentsMargins(8, 8, 8, 8);
     layout->setSpacing(6);
 
-    QHBoxLayout *header = new QHBoxLayout();
-    header->setSpacing(4);
     m_folderLabel = new QLabel(tr("未打开文件夹"), content);
     m_folderLabel->setSizePolicy(QSizePolicy::Ignored, QSizePolicy::Preferred);
-    QToolButton *refreshButton = new QToolButton(content);
-    refreshButton->setText(tr("刷新"));
-    refreshButton->setToolTip(tr("重新扫描文件夹里的 Markdown 文件"));
-    header->addWidget(m_folderLabel, 1);
-    header->addWidget(refreshButton);
-    layout->addLayout(header);
+    layout->addWidget(m_folderLabel);
 
     m_fileList = new QListWidget(content);
     m_fileList->setFrameShape(QFrame::NoFrame);
@@ -252,8 +249,13 @@ void MainWindow::createSidebar()
     addDockWidget(Qt::LeftDockWidgetArea, m_sidebar);
     resizeDocks({m_sidebar}, {250}, Qt::Horizontal);
 
-    connect(refreshButton, &QToolButton::clicked, this, &MainWindow::refreshFolder);
     connect(m_fileList, &QListWidget::itemClicked, this, &MainWindow::openSidebarItem);
+
+    // 列表自己刷新：没有“刷新”按钮，每 5 秒比对一次文件集合，变了才重建。
+    m_folderRefreshTimer = new QTimer(this);
+    m_folderRefreshTimer->setInterval(5000);
+    connect(m_folderRefreshTimer, &QTimer::timeout, this, &MainWindow::refreshFolder);
+    m_folderRefreshTimer->start();
 }
 
 void MainWindow::createMenus()
@@ -330,7 +332,16 @@ void MainWindow::createMenus()
 
 void MainWindow::createStatusBar()
 {
-    // 左下角的 <src> 开关：切到源代码模式。
+    // 左下角：侧栏开关 + 源代码模式开关。
+    m_sidebarButton = new QToolButton(this);
+    m_sidebarButton->setText(tr("侧栏"));
+    m_sidebarButton->setCheckable(true);
+    m_sidebarButton->setChecked(true);
+    m_sidebarButton->setCursor(Qt::PointingHandCursor);
+    m_sidebarButton->setToolTip(tr("显示 / 隐藏文件夹侧栏（Ctrl+B）"));
+    statusBar()->addWidget(m_sidebarButton);
+    connect(m_sidebarButton, &QToolButton::toggled, m_sidebarAction, &QAction::setChecked);
+
     m_sourceButton = new QToolButton(this);
     m_sourceButton->setText(QStringLiteral("<src>"));
     m_sourceButton->setCheckable(true);
@@ -719,24 +730,13 @@ void MainWindow::openFolder(const QString &path)
     m_sidebarAction->setChecked(true);
 }
 
-void MainWindow::refreshFolder()
+QStringList MainWindow::scanFolder() const
 {
-    if (!m_fileList)
-        return;
-
-    m_fileList->clear();
-
-    if (m_folderPath.isEmpty() || !QFileInfo(m_folderPath).isDir()) {
-        m_folderLabel->setText(tr("未打开文件夹"));
-        m_folderLabel->setToolTip(tr("文件 → 打开文件夹…"));
-        return;
-    }
+    QStringList files;
+    if (m_folderPath.isEmpty() || !QFileInfo(m_folderPath).isDir())
+        return files;
 
     const QDir root(m_folderPath);
-    m_folderLabel->setText(root.dirName().isEmpty() ? m_folderPath : root.dirName());
-    m_folderLabel->setToolTip(QDir::toNativeSeparators(m_folderPath));
-
-    QStringList files;
     QDirIterator iterator(m_folderPath,
                           {QStringLiteral("*.md"), QStringLiteral("*.markdown"),
                            QStringLiteral("*.mdown"), QStringLiteral("*.mkd")},
@@ -753,6 +753,47 @@ void MainWindow::refreshFolder()
         return root.relativeFilePath(left).compare(root.relativeFilePath(right),
                                                    Qt::CaseInsensitive) < 0;
     });
+    return files;
+}
+
+void MainWindow::refreshFolder()
+{
+    if (!m_fileList)
+        return;
+
+    if (m_folderPath.isEmpty() || !QFileInfo(m_folderPath).isDir()) {
+        if (m_fileList->count() > 0 || m_displayedFolder != m_folderPath) {
+            m_fileList->clear();
+            m_displayedFolder = m_folderPath;
+            m_folderLabel->setText(tr("未打开文件夹"));
+            m_folderLabel->setToolTip(tr("文件 → 打开文件夹…"));
+        }
+        return;
+    }
+
+    const QDir root(m_folderPath);
+    if (m_displayedFolder != m_folderPath) {
+        m_displayedFolder = m_folderPath;
+        m_fileList->clear();
+        m_folderLabel->setText(root.dirName().isEmpty() ? m_folderPath : root.dirName());
+        m_folderLabel->setToolTip(QDir::toNativeSeparators(m_folderPath));
+    }
+
+    const QStringList files = scanFolder();
+
+    // 和当前显示的内容一致就什么都不做，避免每 5 秒闪一下、丢失选中项。
+    QStringList shown;
+    shown.reserve(m_fileList->count());
+    for (int index = 0; index < m_fileList->count(); ++index) {
+        const QString path = m_fileList->item(index)->data(Qt::UserRole).toString();
+        if (!path.isEmpty())
+            shown.append(path);
+    }
+    if (files == shown)
+        return;
+
+    const QString selectedPath = m_currentPath;
+    m_fileList->clear();
 
     for (const QString &filePath : files) {
         QListWidgetItem *item = new QListWidgetItem(root.relativeFilePath(filePath), m_fileList);
@@ -765,7 +806,7 @@ void MainWindow::refreshFolder()
         empty->setFlags(Qt::NoItemFlags);
     }
 
-    selectInSidebar(m_currentPath);
+    selectInSidebar(selectedPath);
 }
 
 void MainWindow::openSidebarItem(QListWidgetItem *item)

src/MainWindow.h

@@ -54,6 +54,7 @@ private:
     void refreshFolder();
     void openSidebarItem(QListWidgetItem *item);
     void selectInSidebar(const QString &path);
+    QStringList scanFolder() const;
     void setSourceModeEnabled(bool enabled);
 
     void changeZoom(int direction);
@@ -76,7 +77,10 @@ private:
     QListWidget *m_fileList = nullptr;
     QLabel *m_folderLabel = nullptr;
     QToolButton *m_sourceButton = nullptr;
+    QToolButton *m_sidebarButton = nullptr;
+    QTimer *m_folderRefreshTimer = nullptr;
     QString m_folderPath;
+    QString m_displayedFolder;
 
     QString m_currentPath;
     Eol m_eol = Eol::Lf;

src/MarkdownEditor.cpp

@@ -74,6 +74,8 @@ MarkdownEditor::MarkdownEditor(QWidget *parent)
 
     m_lineNumberArea = new LineNumberArea(this);
     m_highlighter = new MarkdownHighlighter(document());
+    m_activeBlock = textCursor().blockNumber();
+    m_highlighter->setActiveBlock(m_activeBlock);
 
     connect(this, &QPlainTextEdit::blockCountChanged,
             this, &MarkdownEditor::updateLineNumberAreaWidth);
@@ -81,6 +83,8 @@ MarkdownEditor::MarkdownEditor(QWidget *parent)
             this, &MarkdownEditor::updateLineNumberArea);
     connect(this, &QPlainTextEdit::cursorPositionChanged,
             this, &MarkdownEditor::updateCurrentLineHighlight);
+    connect(this, &QPlainTextEdit::cursorPositionChanged,
+            this, &MarkdownEditor::updateActiveBlock);
     connect(ThemeManager::instance(), &ThemeManager::schemeChanged,
             this, &MarkdownEditor::applyTheme);
 
@@ -159,11 +163,15 @@ void MarkdownEditor::applyEditorFont()
     document()->setDefaultFont(font);
     setTabStopDistance(QFontMetricsF(font).horizontalAdvance(QLatin1Char(' ')) * 4.0);
     updateLineNumberAreaWidth(0);
+
+    // 标题字号是根据正文大小算的，缩放后要让高亮层重建格式。
+    if (m_highlighter)
+        m_highlighter->refreshAppearance();
 }
 
 void MarkdownEditor::updateLineNumberAreaWidth(int)
 {
-    setViewportMargins(m_sourceMode ? 0 : lineNumberAreaWidth(), 0, 0, 0);
+    setViewportMargins(lineNumberAreaWidth(), 0, 0, 0);
 }
 
 void MarkdownEditor::updateLineNumberArea(const QRect &rect, int dy)
@@ -179,11 +187,6 @@ void MarkdownEditor::updateLineNumberArea(const QRect &rect, int dy)
 
 void MarkdownEditor::updateCurrentLineHighlight()
 {
-    if (m_sourceMode) {
-        setExtraSelections({});
-        return;
-    }
-
     QTextEdit::ExtraSelection selection;
     selection.format.setBackground(ThemeManager::instance()->colors().currentLine);
     selection.format.setProperty(QTextFormat::FullWidthSelection, true);
@@ -205,24 +208,34 @@ void MarkdownEditor::setSourceMode(bool enabled)
         return;
 
     m_sourceMode = enabled;
-    m_highlighter->setHighlightingEnabled(!enabled);
-
-    if (enabled)
-        setExtraSelections({});
-    else
-        updateCurrentLineHighlight();
-
-    m_lineNumberArea->setVisible(!enabled);
-    updateLineNumberAreaWidth(0);
-
-    const QRect rect = contentsRect();
-    m_lineNumberArea->setGeometry(QRect(rect.left(), rect.top(),
-                                        lineNumberAreaWidth(), rect.height()));
+    m_activeBlock = textCursor().blockNumber();
+    m_highlighter->setActiveBlock(m_activeBlock);
+    m_highlighter->setRendered(!enabled);
 
+    updateCurrentLineHighlight();
     viewport()->update();
     emit sourceModeChanged(enabled);
 }
 
+void MarkdownEditor::updateActiveBlock()
+{
+    if (m_sourceMode)
+        return;
+
+    const int blockNumber = textCursor().blockNumber();
+    if (blockNumber == m_activeBlock)
+        return;
+
+    const QTextBlock previous = document()->findBlockByNumber(m_activeBlock);
+    m_activeBlock = blockNumber;
+    m_highlighter->setActiveBlock(blockNumber);
+
+    // 只重排两行：离开的那行重新隐藏标记，进入的那行露出来。
+    if (previous.isValid())
+        m_highlighter->rehighlightBlock(previous);
+    m_highlighter->rehighlightBlock(textCursor().block());
+}
+
 void MarkdownEditor::selectedBlockRange(int *firstBlock, int *lastBlock) const
 {
     const QTextCursor cursor = textCursor();

src/MarkdownEditor.h

@@ -48,6 +48,7 @@ private slots:
     void updateLineNumberAreaWidth(int newBlockCount);
     void updateLineNumberArea(const QRect &rect, int dy);
     void updateCurrentLineHighlight();
+    void updateActiveBlock();
     void applyTheme();
 
 private:
@@ -63,4 +64,5 @@ private:
     MarkdownHighlighter *m_highlighter = nullptr;
     int m_fontPointSize = 12;
     bool m_sourceMode = false;
+    int m_activeBlock = -1;
 };

src/MarkdownHighlighter.cpp

@@ -2,7 +2,9 @@
 
 #include "ThemeManager.h"
 
+#include <QTextBlock>
 #include <QTextDocument>
+#include <QTextLayout>
 
 namespace {
 constexpr int StateNormal = 0;
@@ -19,13 +21,45 @@ MarkdownHighlighter::MarkdownHighlighter(QTextDocument *document)
     });
 }
 
+void MarkdownHighlighter::setRendered(bool rendered)
+{
+    if (m_rendered == rendered)
+        return;
+    m_rendered = rendered;
+    rehighlight();
+}
+
+void MarkdownHighlighter::setActiveBlock(int blockNumber)
+{
+    m_activeBlock = blockNumber;
+}
+
+void MarkdownHighlighter::refreshAppearance()
+{
+    rebuildFormats();
+    rehighlight();
+}
+
+bool MarkdownHighlighter::isActiveLine() const
+{
+    return m_rendered && currentBlock().blockNumber() == m_activeBlock;
+}
+
 void MarkdownHighlighter::rebuildFormats()
 {
     const ThemeColors &c = ThemeManager::instance()->colors();
 
-    m_headingFormat = QTextCharFormat();
-    m_headingFormat.setForeground(c.heading);
-    m_headingFormat.setFontWeight(QFont::DemiBold);
+    qreal base = 12.0;
+    if (document() && document()->defaultFont().pointSizeF() > 0.5)
+        base = document()->defaultFont().pointSizeF();
+
+    static const qreal scales[6] = {1.75, 1.50, 1.30, 1.14, 1.04, 1.0};
+    for (int level = 0; level < 6; ++level) {
+        m_headingFormats[level] = QTextCharFormat();
+        m_headingFormats[level].setForeground(c.heading);
+        m_headingFormats[level].setFontWeight(QFont::Bold);
+        m_headingFormats[level].setFontPointSize(base * scales[level]);
+    }
 
     m_headingMarkerFormat = QTextCharFormat();
     m_headingMarkerFormat.setForeground(c.headingMarker);
@@ -34,6 +68,11 @@ void MarkdownHighlighter::rebuildFormats()
     m_strongFormat.setForeground(c.strong);
     m_strongFormat.setFontWeight(QFont::Bold);
 
+    m_boldItalicFormat = QTextCharFormat();
+    m_boldItalicFormat.setForeground(c.strong);
+    m_boldItalicFormat.setFontWeight(QFont::Bold);
+    m_boldItalicFormat.setFontItalic(true);
+
     m_emphasisFormat = QTextCharFormat();
     m_emphasisFormat.setForeground(c.emphasis);
     m_emphasisFormat.setFontItalic(true);
@@ -46,6 +85,7 @@ void MarkdownHighlighter::rebuildFormats()
 
     m_linkFormat = QTextCharFormat();
     m_linkFormat.setForeground(c.link);
+    m_linkFormat.setFontUnderline(true);
 
     m_urlFormat = QTextCharFormat();
     m_urlFormat.setForeground(c.linkUrl);
@@ -74,125 +114,234 @@ void MarkdownHighlighter::rebuildFormats()
     m_strikeFormat.setForeground(c.quote);
 }
 
+QTextCharFormat MarkdownHighlighter::compose(const QTextCharFormat &specific) const
+{
+    QTextCharFormat result = m_blockBase;
+    result.merge(specific);
+    return result;
+}
+
+QTextCharFormat MarkdownHighlighter::hiddenFormat(const QColor &background) const
+{
+    // 用“和背景同色 + 极小字号”把标记藏起来：文字仍然留在文档里，
+    // 光标移回来时重新显示，所以不影响编辑和撤销。
+    QTextCharFormat format;
+    format.setForeground(background);
+    format.setFontPointSize(0.5);
+    return format;
+}
+
 void MarkdownHighlighter::apply(int start, int length, const QTextCharFormat &format)
 {
     if (length > 0)
         setFormat(start, length, format);
 }
 
-void MarkdownHighlighter::applyPattern(const QRegularExpression &pattern, const QString &text,
-                                       const QTextCharFormat &format)
+void MarkdownHighlighter::applyDelimited(const QRegularExpression &pattern, const QString &text,
+                                         const QTextCharFormat &contentFormat, int contentGroup,
+                                         const QColor &hideAgainst)
 {
-    auto it = pattern.globalMatch(text);
-    while (it.hasNext()) {
-        const QRegularExpressionMatch match = it.next();
-        apply(match.capturedStart(), match.capturedLength(), format);
-    }
-}
+    auto iterator = pattern.globalMatch(text);
+    while (iterator.hasNext()) {
+        const QRegularExpressionMatch match = iterator.next();
+        const int start = match.capturedStart(contentGroup);
+        const int length = match.capturedLength(contentGroup);
+        if (length <= 0)
+            continue;
 
-void MarkdownHighlighter::setHighlightingEnabled(bool enabled)
-{
-    if (m_enabled == enabled)
-        return;
-    m_enabled = enabled;
-    rehighlight();
+        if (m_rendered && !isActiveLine()) {
+            apply(start, length, compose(contentFormat));
+            const int matchStart = match.capturedStart();
+            const int matchEnd = matchStart + match.capturedLength();
+            if (start > matchStart)
+                apply(matchStart, start - matchStart, compose(hiddenFormat(hideAgainst)));
+            if (matchEnd > start + length)
+                apply(start + length, matchEnd - start - length,
+                      compose(hiddenFormat(hideAgainst)));
+        } else {
+            // 源码模式，或光标正停在这一行：整段按内容样式显示，标记保留。
+            apply(match.capturedStart(), match.capturedLength(), compose(contentFormat));
+        }
+    }
 }
 
 void MarkdownHighlighter::highlightBlock(const QString &text)
 {
     setCurrentBlockState(StateNormal);
-    if (!m_enabled || text.isEmpty())
+    m_blockBase = QTextCharFormat();
+    if (text.isEmpty())
         return;
 
+    const ThemeColors &c = ThemeManager::instance()->colors();
+    const bool rendered = m_rendered;
+    const bool active = isActiveLine();
+
     static const QRegularExpression fencePattern(QStringLiteral("^\\s{0,3}(?:```|~~~)"));
+    const bool inFence = previousBlockState() == StateInFence;
+    const bool fenceLine = fencePattern.match(text).hasMatch();
 
-    // ---- 围栏代码块：跨行状态机 ----------------------------------------
-    if (previousBlockState() == StateInFence) {
-        apply(0, text.length(), m_codeFormat);
-        if (!fencePattern.match(text).hasMatch())
+    // ---- 围栏代码块 -----------------------------------------------------
+    if (inFence) {
+        if (!fenceLine)
             setCurrentBlockState(StateInFence);
+        if (rendered && fenceLine && !active) {
+            apply(0, text.length(), hiddenFormat(c.editorBase));
+        } else {
+            m_blockBase = m_codeFormat;
+            apply(0, text.length(), m_codeFormat);
+        }
         return;
     }
-    if (fencePattern.match(text).hasMatch()) {
-        apply(0, text.length(), m_codeFormat);
+    if (fenceLine) {
         setCurrentBlockState(StateInFence);
+        if (rendered && !active)
+            apply(0, text.length(), hiddenFormat(c.editorBase));
+        else
+            apply(0, text.length(), m_codeFormat);
         return;
     }
 
-    // ---- 块级语法 ------------------------------------------------------
-    static const QRegularExpression headingPattern(
-        QStringLiteral("^\\s{0,3}(#{1,6})(?:\\s+|$)"));
+    // ---- 标题 -----------------------------------------------------------
+    static const QRegularExpression headingPattern(QStringLiteral("^\\s{0,3}(#{1,6})(\\s+)"));
     const QRegularExpressionMatch heading = headingPattern.match(text);
     if (heading.hasMatch()) {
-        apply(0, text.length(), m_headingFormat);
-        apply(heading.capturedStart(1), heading.capturedLength(1), m_headingMarkerFormat);
+        const int level = qBound(1, heading.capturedLength(1), 6);
+        m_blockBase.merge(m_headingFormats[level - 1]);
+        apply(0, text.length(), m_blockBase);
+
+        const int markerStart = heading.capturedStart(1);
+        const int markerLength = heading.capturedLength(1) + heading.capturedLength(2);
+        if (rendered && !active)
+            apply(markerStart, markerLength, compose(hiddenFormat(c.editorBase)));
+        else
+            apply(markerStart, markerLength, compose(m_headingMarkerFormat));
     }
 
+    // ---- 引用 -----------------------------------------------------------
     static const QRegularExpression quotePattern(QStringLiteral("^\\s{0,3}(>+)"));
     const QRegularExpressionMatch quote = quotePattern.match(text);
     if (quote.hasMatch()) {
-        apply(0, text.length(), m_quoteFormat);
-        apply(quote.capturedStart(1), quote.capturedLength(1), m_quoteMarkerFormat);
+        m_blockBase.merge(m_quoteFormat);
+        apply(0, text.length(), m_blockBase);
+        if (rendered && !active)
+            apply(quote.capturedStart(1), quote.capturedLength(1),
+                  compose(hiddenFormat(c.editorBase)));
+        else
+            apply(quote.capturedStart(1), quote.capturedLength(1), compose(m_quoteMarkerFormat));
     }
 
+    // ---- 分隔线 / 列表 ---------------------------------------------------
     static const QRegularExpression rulePattern(
         QStringLiteral("^\\s{0,3}(?:(?:\\*\\s*){3,}|(?:-\\s*){3,}|(?:_\\s*){3,})$"));
-    const QRegularExpressionMatch rule = rulePattern.match(text);
-    if (rule.hasMatch()) {
-        apply(0, text.length(), m_ruleFormat);
+    if (rulePattern.match(text).hasMatch()) {
+        apply(0, text.length(), compose(m_ruleFormat));
     } else {
         static const QRegularExpression taskPattern(
             QStringLiteral("^\\s*[-+*]\\s+\\[([ xX])\\]"));
         const QRegularExpressionMatch task = taskPattern.match(text);
         if (task.hasMatch()) {
-            apply(task.capturedStart(), task.capturedLength(), m_listMarkerFormat);
+            apply(task.capturedStart(), task.capturedLength(), compose(m_listMarkerFormat));
             if (task.capturedLength(1) > 0) {
-                const bool done = task.captured(1).compare(QLatin1String("x"), Qt::CaseInsensitive) == 0;
+                const bool done = task.captured(1).compare(QLatin1String("x"),
+                                                           Qt::CaseInsensitive) == 0;
                 apply(task.capturedStart(1), task.capturedLength(1),
-                      done ? m_taskDoneFormat : m_listMarkerFormat);
+                      compose(done ? m_taskDoneFormat : m_listMarkerFormat));
             }
         } else {
             static const QRegularExpression listPattern(
                 QStringLiteral("^(\\s*)([-+*]|\\d{1,9}[.)])(\\s+)"));
             const QRegularExpressionMatch list = listPattern.match(text);
             if (list.hasMatch())
-                apply(list.capturedStart(2), list.capturedLength(2), m_listMarkerFormat);
+                apply(list.capturedStart(2), list.capturedLength(2), compose(m_listMarkerFormat));
         }
     }
 
-    // ---- 行内语法 ------------------------------------------------------
+    // ---- 链接 / 图片 -----------------------------------------------------
     static const QRegularExpression linkPattern(
         QStringLiteral("!?\\[([^\\]]*)\\]\\(([^)\\s]*)(?:\\s+\"([^\"]*)\")?\\)"));
     auto links = linkPattern.globalMatch(text);
     while (links.hasNext()) {
         const QRegularExpressionMatch match = links.next();
-        apply(match.capturedStart(1), match.capturedLength(1), m_linkFormat);
-        apply(match.capturedStart(2), match.capturedLength(2), m_urlFormat);
+        const int labelStart = match.capturedStart(1);
+        const int labelLength = match.capturedLength(1);
+        const int matchEnd = match.capturedStart() + match.capturedLength();
+
+        apply(labelStart, labelLength, compose(m_linkFormat));
+
+        if (rendered && !active) {
+            if (labelStart > match.capturedStart())
+                apply(match.capturedStart(), labelStart - match.capturedStart(),
+                      compose(hiddenFormat(c.editorBase)));
+            const int suffixStart = labelStart + labelLength;
+            if (matchEnd > suffixStart)
+                apply(suffixStart, matchEnd - suffixStart,
+                      compose(hiddenFormat(c.editorBase)));
+        } else if (match.capturedLength(2) > 0) {
+            apply(match.capturedStart(2), match.capturedLength(2), compose(m_urlFormat));
+        }
     }
 
     static const QRegularExpression autoLinkPattern(QStringLiteral("<(https?://[^>]+)>"));
-    auto autolinks = autoLinkPattern.globalMatch(text);
-    while (autolinks.hasNext()) {
-        const QRegularExpressionMatch match = autolinks.next();
-        apply(match.capturedStart(1), match.capturedLength(1), m_urlFormat);
+    auto autoLinks = autoLinkPattern.globalMatch(text);
+    while (autoLinks.hasNext()) {
+        const QRegularExpressionMatch match = autoLinks.next();
+        apply(match.capturedStart(1), match.capturedLength(1), compose(m_urlFormat));
+        if (rendered && !active) {
+            apply(match.capturedStart(), 1, compose(hiddenFormat(c.editorBase)));
+            apply(match.capturedStart() + match.capturedLength() - 1, 1,
+                  compose(hiddenFormat(c.editorBase)));
+        }
     }
 
+    // ---- 行内强调 --------------------------------------------------------
+    // 内容里禁止出现定界符，否则 **粗体** 会被更宽泛的 *斜体* 规则先吃掉。
+    static const QRegularExpression boldAsterisk(
+        QStringLiteral("\\*\\*(?=\\S)([^*\\n]+?)(?<=\\S)\\*\\*"));
+    applyDelimited(boldAsterisk, text, m_strongFormat, 1, c.editorBase);
+
+    static const QRegularExpression boldUnderscore(
+        QStringLiteral("__(?=\\S)([^_\\n]+?)(?<=\\S)__"));
+    applyDelimited(boldUnderscore, text, m_strongFormat, 1, c.editorBase);
+
+    static const QRegularExpression italicAsterisk(
+        QStringLiteral("(?<![*\\w])\\*(?!\\*)(?=\\S)([^*\\n]+?)(?<=\\S)\\*(?!\\*)"));
+    applyDelimited(italicAsterisk, text, m_emphasisFormat, 1, c.editorBase);
+
+    static const QRegularExpression italicUnderscore(
+        QStringLiteral("(?<![_\\w])_(?!_)(?=\\S)([^_\\n]+?)(?<=\\S)_(?![\\w_])"));
+    applyDelimited(italicUnderscore, text, m_emphasisFormat, 1, c.editorBase);
+
+    static const QRegularExpression strikePattern(
+        QStringLiteral("~~(?=\\S)([^~\\n]+?)(?<=\\S)~~"));
+    applyDelimited(strikePattern, text, m_strikeFormat, 1, c.editorBase);
+
+    // 三重强调最后应用，压住上面的加粗 / 斜体。
     static const QRegularExpression boldItalicPattern(
-        QStringLiteral("(\\*{3}|_{3})(?=\\S)(.+?)(?<=\\S)\\1"));
-    applyPattern(boldItalicPattern, text, m_strongFormat);
-    applyPattern(boldItalicPattern, text, m_emphasisFormat);
+        QStringLiteral("\\*\\*\\*(?=\\S)([^*\\n]+?)(?<=\\S)\\*\\*\\*"));
+    applyDelimited(boldItalicPattern, text, m_boldItalicFormat, 1, c.editorBase);
 
-    static const QRegularExpression boldPattern(QStringLiteral("(\\*\\*|__)(?=\\S)(.+?)(?<=\\S)\\1"));
-    applyPattern(boldPattern, text, m_strongFormat);
+    // ---- 行内代码（最后，压住内部的强调）---------------------------------
+    static const QRegularExpression codePattern(QStringLiteral("(`+)([^`\\n]+)\\1"));
+    auto codes = codePattern.globalMatch(text);
+    while (codes.hasNext()) {
+        const QRegularExpressionMatch match = codes.next();
+        const int matchStart = match.capturedStart();
+        const int matchEnd = matchStart + match.capturedLength();
+        const QTextCharFormat span = compose(m_codeFormat);
+        apply(matchStart, match.capturedLength(), span);
 
-    static const QRegularExpression italicPattern(
-        QStringLiteral("(?<![*_\\w])([*_])(?=\\S)(.+?)(?<=\\S)\\1(?![*_\\w])"));
-    applyPattern(italicPattern, text, m_emphasisFormat);
-
-    static const QRegularExpression strikePattern(QStringLiteral("~~(?=\\S)(.+?)(?<=\\S)~~"));
-    applyPattern(strikePattern, text, m_strikeFormat);
-
-    // 行内代码最后着色，压住内部的加粗 / 斜体。
-    static const QRegularExpression inlineCodePattern(QStringLiteral("`[^`\\n]+`"));
-    applyPattern(inlineCodePattern, text, m_codeFormat);
+        if (rendered && !active) {
+            const int contentStart = match.capturedStart(2);
+            const int contentLength = match.capturedLength(2);
+            if (contentLength <= 0)
+                continue;
+            QTextCharFormat hidden = span;
+            hidden.merge(hiddenFormat(c.codeBackground));
+            if (contentStart > matchStart)
+                apply(matchStart, contentStart - matchStart, hidden);
+            const int suffixStart = contentStart + contentLength;
+            if (matchEnd > suffixStart)
+                apply(suffixStart, matchEnd - suffixStart, hidden);
+        }
+    }
 }

src/MarkdownHighlighter.h

@@ -1,14 +1,20 @@
 #pragma once
 
+#include <QColor>
 #include <QRegularExpression>
 #include <QSyntaxHighlighter>
 #include <QTextCharFormat>
 
-/// Markdown 语法着色。
+/// Markdown 着色与“就地渲染”。
 ///
-/// 只做“逐行着色”，不改动文档内容：标题、引用、列表、行内样式、
-/// 链接以及跨行的围栏代码块。颜色全部取自 ThemeManager，
-/// 主题切换后自动重建格式并重新着色。
+/// 两种形态：
+///  - 渲染模式（默认，对应界面的“编辑器模式”）：隐藏 #、**、反引号等标记，
+///    标题按级别放大、加粗文本真加粗、链接只留文字；光标所在行会露出原始标记，
+///    方便直接修改。
+///  - 源码模式：原样显示所有标记，只做着色。
+///
+/// 注意：QSyntaxHighlighter::setFormat 是“整段替换”而不是合并，所以这里
+/// 每一段都先和当前行的基础格式（标题 / 引用 / 代码块）合并后再设置。
 class MarkdownHighlighter : public QSyntaxHighlighter
 {
     Q_OBJECT
@@ -16,8 +22,15 @@ class MarkdownHighlighter : public QSyntaxHighlighter
 public:
     explicit MarkdownHighlighter(QTextDocument *document = nullptr);
 
-    /// 源代码模式会关掉着色，但不改文档内容（rehighlight 会清掉旧格式）。
-    void setHighlightingEnabled(bool enabled);
+    void setRendered(bool rendered);
+    bool isRendered() const { return m_rendered; }
+
+    /// 光标所在行；渲染模式下这一行不隐藏标记。
+    void setActiveBlock(int blockNumber);
+    int activeBlock() const { return m_activeBlock; }
+
+    /// 主题或字号变化后重建格式并重新着色。
+    void refreshAppearance();
 
 protected:
     void highlightBlock(const QString &text) override;
@@ -25,12 +38,21 @@ protected:
 private:
     void rebuildFormats();
     void apply(int start, int length, const QTextCharFormat &format);
-    void applyPattern(const QRegularExpression &pattern, const QString &text,
-                      const QTextCharFormat &format);
+    void applyDelimited(const QRegularExpression &pattern, const QString &text,
+                        const QTextCharFormat &contentFormat, int contentGroup,
+                        const QColor &hideAgainst);
+    QTextCharFormat compose(const QTextCharFormat &specific) const;
+    QTextCharFormat hiddenFormat(const QColor &background) const;
+    bool isActiveLine() const;
 
-    QTextCharFormat m_headingFormat;
+    bool m_rendered = true;
+    int m_activeBlock = -1;
+    QTextCharFormat m_blockBase;
+
+    QTextCharFormat m_headingFormats[6];
     QTextCharFormat m_headingMarkerFormat;
     QTextCharFormat m_strongFormat;
+    QTextCharFormat m_boldItalicFormat;
     QTextCharFormat m_emphasisFormat;
     QTextCharFormat m_codeFormat;
     QTextCharFormat m_linkFormat;
@@ -41,5 +63,4 @@ private:
     QTextCharFormat m_ruleFormat;
     QTextCharFormat m_taskDoneFormat;
     QTextCharFormat m_strikeFormat;
-    bool m_enabled = true;
 };

src/main.cpp

@@ -4,6 +4,7 @@
 #include <QApplication>
 #include <QCommandLineOption>
 #include <QCommandLineParser>
+#include <QIcon>
 #include <QPixmap>
 #include <QStyleFactory>
 #include <QTimer>
@@ -15,6 +16,7 @@ int main(int argc, char *argv[])
 
     QApplication app(argc, argv);
     QApplication::setStyle(QStyleFactory::create(QStringLiteral("Fusion")));
+    QApplication::setWindowIcon(QIcon(QStringLiteral(":/logo.png")));
 
     QCoreApplication::setOrganizationName(QStringLiteral("VoiletMark"));
     QCoreApplication::setApplicationName(QStringLiteral("VoiletMark"));