feat: Multi-selection + action bar in MailListView

- MailListView: ExtendedSelection mode for both tree and list views
- Action bar (blue bar) appears when items selected
- Select all checkbox + counter label
- Batch actions: Flag, Mark unread, Move (TODO), Delete, Exit selection
- Signals: selectionChanged, batchFlagRequested, batchDeleteRequested, batchMarkUnreadRequested, batchMoveRequested
- enterMultiSelectMode()/exitMultiSelectMode() state management
- Works in both normal and compact views

build/CMakeFiles/wino-mail-qt.dir/compiler_depend.internal

@@ -27264,6 +27264,7 @@ CMakeFiles/wino-mail-qt.dir/src/ui/delegates/CompactMailDelegate.cpp.o
  /usr/include/x86_64-linux-gnu/qt6/QtGui/QFontMetrics
  /usr/include/x86_64-linux-gnu/qt6/QtGui/QMouseEvent
  /usr/include/x86_64-linux-gnu/qt6/QtGui/QPainter
+ /usr/include/x86_64-linux-gnu/qt6/QtGui/QPainterPath
  /usr/include/x86_64-linux-gnu/qt6/QtGui/QPixmap
  /usr/include/x86_64-linux-gnu/qt6/QtGui/QTransform
  /usr/include/x86_64-linux-gnu/qt6/QtGui/qaction.h
@@ -27286,6 +27287,7 @@ CMakeFiles/wino-mail-qt.dir/src/ui/delegates/CompactMailDelegate.cpp.o
  /usr/include/x86_64-linux-gnu/qt6/QtGui/qkeysequence.h
  /usr/include/x86_64-linux-gnu/qt6/QtGui/qpaintdevice.h
  /usr/include/x86_64-linux-gnu/qt6/QtGui/qpainter.h
+ /usr/include/x86_64-linux-gnu/qt6/QtGui/qpainterpath.h
  /usr/include/x86_64-linux-gnu/qt6/QtGui/qpalette.h
  /usr/include/x86_64-linux-gnu/qt6/QtGui/qpen.h
  /usr/include/x86_64-linux-gnu/qt6/QtGui/qpixelformat.h
@@ -28586,12 +28588,14 @@ CMakeFiles/wino-mail-qt.dir/src/ui/maillistview.cpp.o
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QLabel
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QLineEdit
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QListView
+ /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QMenu
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QPushButton
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QScrollBar
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QStackedWidget
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QStyle
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QStyleOptionViewItem
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QStyledItemDelegate
+ /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QToolButton
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QTreeView
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QVBoxLayout
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QWidget
@@ -28613,6 +28617,7 @@ CMakeFiles/wino-mail-qt.dir/src/ui/maillistview.cpp.o
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qlayoutitem.h
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qlineedit.h
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qlistview.h
+ /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qmenu.h
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qpushbutton.h
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qrubberband.h
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qscrollbar.h
@@ -28624,6 +28629,7 @@ CMakeFiles/wino-mail-qt.dir/src/ui/maillistview.cpp.o
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qstyleoption.h
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qtabbar.h
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qtabwidget.h
+ /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qtoolbutton.h
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qtreeview.h
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qtwidgets-config.h
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qtwidgetsexports.h

build/CMakeFiles/wino-mail-qt.dir/compiler_depend.make

@@ -27216,6 +27216,7 @@ CMakeFiles/wino-mail-qt.dir/src/ui/delegates/CompactMailDelegate.cpp.o: /mnt/c/U
   /usr/include/x86_64-linux-gnu/qt6/QtGui/QFontMetrics \
   /usr/include/x86_64-linux-gnu/qt6/QtGui/QMouseEvent \
   /usr/include/x86_64-linux-gnu/qt6/QtGui/QPainter \
+  /usr/include/x86_64-linux-gnu/qt6/QtGui/QPainterPath \
   /usr/include/x86_64-linux-gnu/qt6/QtGui/QPixmap \
   /usr/include/x86_64-linux-gnu/qt6/QtGui/QTransform \
   /usr/include/x86_64-linux-gnu/qt6/QtGui/qaction.h \
@@ -27238,6 +27239,7 @@ CMakeFiles/wino-mail-qt.dir/src/ui/delegates/CompactMailDelegate.cpp.o: /mnt/c/U
   /usr/include/x86_64-linux-gnu/qt6/QtGui/qkeysequence.h \
   /usr/include/x86_64-linux-gnu/qt6/QtGui/qpaintdevice.h \
   /usr/include/x86_64-linux-gnu/qt6/QtGui/qpainter.h \
+  /usr/include/x86_64-linux-gnu/qt6/QtGui/qpainterpath.h \
   /usr/include/x86_64-linux-gnu/qt6/QtGui/qpalette.h \
   /usr/include/x86_64-linux-gnu/qt6/QtGui/qpen.h \
   /usr/include/x86_64-linux-gnu/qt6/QtGui/qpixelformat.h \
@@ -28536,12 +28538,14 @@ CMakeFiles/wino-mail-qt.dir/src/ui/maillistview.cpp.o: /mnt/c/Users/javie/Docume
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QLabel \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QLineEdit \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QListView \
+  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QMenu \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QPushButton \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QScrollBar \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QStackedWidget \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QStyle \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QStyleOptionViewItem \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QStyledItemDelegate \
+  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QToolButton \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QTreeView \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QVBoxLayout \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QWidget \
@@ -28563,6 +28567,7 @@ CMakeFiles/wino-mail-qt.dir/src/ui/maillistview.cpp.o: /mnt/c/Users/javie/Docume
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qlayoutitem.h \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qlineedit.h \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qlistview.h \
+  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qmenu.h \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qpushbutton.h \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qrubberband.h \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qscrollbar.h \
@@ -28574,6 +28579,7 @@ CMakeFiles/wino-mail-qt.dir/src/ui/maillistview.cpp.o: /mnt/c/Users/javie/Docume
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qstyleoption.h \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qtabbar.h \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qtabwidget.h \
+  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qtoolbutton.h \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qtreeview.h \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qtwidgets-config.h \
   /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qtwidgetsexports.h \
@@ -42679,8 +42685,6 @@ CMakeFiles/wino-mail-qt.dir/src/core/oauthcallbackserver.cpp.o:
 
 /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QStyleOptionFrame:
 
-/usr/include/x86_64-linux-gnu/qt6/QtGui/qpainterpath.h:
-
 /usr/include/x86_64-linux-gnu/qt6/QtGui/QKeyEvent:
 
 /mnt/c/Users/javie/Documents/Codex/2026-08-11/revisar-2/wino-mail-dtkqt/thirdparty/tags/src/util.hpp:
@@ -42731,6 +42735,8 @@ wino-mail-qt_autogen/GQ6NBGVJMG/moc_accountservice.cpp:
 
 /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QScrollBar:
 
+/usr/include/x86_64-linux-gnu/qt6/QtGui/qpainterpath.h:
+
 /usr/include/x86_64-linux-gnu/qt6/QtGui/QCursor:
 
 /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qfiledialog.h:

build/CMakeFiles/wino-mail-qt.dir/src/ui/maillistview.cpp.o.d

@@ -598,4 +598,8 @@ CMakeFiles/wino-mail-qt.dir/src/ui/maillistview.cpp.o: \
  /usr/include/x86_64-linux-gnu/qt6/QtGui/qcolor.h \
  /usr/include/x86_64-linux-gnu/qt6/QtCore/QRect \
  /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QScrollBar \
- /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qscrollbar.h
+ /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qscrollbar.h \
+ /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QToolButton \
+ /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qtoolbutton.h \
+ /usr/include/x86_64-linux-gnu/qt6/QtWidgets/QMenu \
+ /usr/include/x86_64-linux-gnu/qt6/QtWidgets/qmenu.h

build/wino-mail-qt_autogen/YPKJ5OE7LN/moc_maillistview.cpp

@@ -9,6 +9,7 @@
 #include "../../../src/ui/maillistview.h"
 #include <QtGui/qtextcursor.h>
 #include <QtCore/qmetatype.h>
+#include <QtCore/QList>
 
 #include <QtCore/qtmochelpers.h>
 
@@ -54,6 +55,16 @@ template <> constexpr inline auto MailListView::qt_create_metaobjectdata<qt_meta
         "replyRequested",
         "forwardRequested",
         "markUnreadRequested",
+        "selectionChanged",
+        "QList<int>",
+        "selectedMailIds",
+        "batchFlagRequested",
+        "mailIds",
+        "flagged",
+        "batchDeleteRequested",
+        "batchMarkUnreadRequested",
+        "batchMoveRequested",
+        "targetFolderId",
         "onRowSelected",
         "QModelIndex",
         "index",
@@ -78,7 +89,16 @@ template <> constexpr inline auto MailListView::qt_create_metaobjectdata<qt_meta
         "onRowsInserted",
         "parent",
         "first",
-        "last"
+        "last",
+        "onSelectionChanged",
+        "onSelectAllToggled",
+        "checked",
+        "onBatchFlagClicked",
+        "onBatchMarkUnreadClicked",
+        "onBatchMoveClicked",
+        "onBatchDeleteClicked",
+        "enterMultiSelectMode",
+        "exitMultiSelectMode"
     };
 
     QtMocHelpers::UintData qt_methods {
@@ -120,72 +140,110 @@ template <> constexpr inline auto MailListView::qt_create_metaobjectdata<qt_meta
         QtMocHelpers::SignalData<void(int)>(14, 2, QMC::AccessPublic, QMetaType::Void, {{
             { QMetaType::Int, 3 },
         }}),
-        // Slot 'onRowSelected'
+        // Signal 'selectionChanged'
-        QtMocHelpers::SlotData<void(const QModelIndex &)>(15, 2, QMC::AccessPrivate, QMetaType::Void, {{
+        QtMocHelpers::SignalData<void(const QVector<int> &)>(15, 2, QMC::AccessPublic, QMetaType::Void, {{
             { 0x80000000 | 16, 17 },
         }}),
+        // Signal 'batchFlagRequested'
+        QtMocHelpers::SignalData<void(const QVector<int> &, bool)>(18, 2, QMC::AccessPublic, QMetaType::Void, {{
+            { 0x80000000 | 16, 19 }, { QMetaType::Bool, 20 },
+        }}),
+        // Signal 'batchDeleteRequested'
+        QtMocHelpers::SignalData<void(const QVector<int> &)>(21, 2, QMC::AccessPublic, QMetaType::Void, {{
+            { 0x80000000 | 16, 19 },
+        }}),
+        // Signal 'batchMarkUnreadRequested'
+        QtMocHelpers::SignalData<void(const QVector<int> &)>(22, 2, QMC::AccessPublic, QMetaType::Void, {{
+            { 0x80000000 | 16, 19 },
+        }}),
+        // Signal 'batchMoveRequested'
+        QtMocHelpers::SignalData<void(const QVector<int> &, int)>(23, 2, QMC::AccessPublic, QMetaType::Void, {{
+            { 0x80000000 | 16, 19 }, { QMetaType::Int, 24 },
+        }}),
+        // Slot 'onRowSelected'
+        QtMocHelpers::SlotData<void(const QModelIndex &)>(25, 2, QMC::AccessPrivate, QMetaType::Void, {{
+            { 0x80000000 | 26, 27 },
+        }}),
         // Slot 'onSearchTextChanged'
-        QtMocHelpers::SlotData<void(const QString &)>(18, 2, QMC::AccessPrivate, QMetaType::Void, {{
+        QtMocHelpers::SlotData<void(const QString &)>(28, 2, QMC::AccessPrivate, QMetaType::Void, {{
-            { QMetaType::QString, 19 },
+            { QMetaType::QString, 29 },
         }}),
         // Slot 'onFilterChanged'
-        QtMocHelpers::SlotData<void()>(20, 2, QMC::AccessPrivate, QMetaType::Void),
+        QtMocHelpers::SlotData<void()>(30, 2, QMC::AccessPrivate, QMetaType::Void),
         // Slot 'onGroupByChanged'
-        QtMocHelpers::SlotData<void(int)>(21, 2, QMC::AccessPrivate, QMetaType::Void, {{
+        QtMocHelpers::SlotData<void(int)>(31, 2, QMC::AccessPrivate, QMetaType::Void, {{
-            { QMetaType::Int, 17 },
+            { QMetaType::Int, 27 },
         }}),
         // Slot 'onCompactFlagRequested'
-        QtMocHelpers::SlotData<void(int)>(22, 2, QMC::AccessPrivate, QMetaType::Void, {{
+        QtMocHelpers::SlotData<void(int)>(32, 2, QMC::AccessPrivate, QMetaType::Void, {{
             { QMetaType::Int, 3 },
         }}),
         // Slot 'onCompactDeleteRequested'
-        QtMocHelpers::SlotData<void(int)>(23, 2, QMC::AccessPrivate, QMetaType::Void, {{
+        QtMocHelpers::SlotData<void(int)>(33, 2, QMC::AccessPrivate, QMetaType::Void, {{
             { QMetaType::Int, 3 },
         }}),
         // Slot 'onCompactCategoryRequested'
-        QtMocHelpers::SlotData<void(int)>(24, 2, QMC::AccessPrivate, QMetaType::Void, {{
+        QtMocHelpers::SlotData<void(int)>(34, 2, QMC::AccessPrivate, QMetaType::Void, {{
             { QMetaType::Int, 3 },
         }}),
         // Slot 'onCompactMoreRequested'
-        QtMocHelpers::SlotData<void(int, const QPoint &)>(25, 2, QMC::AccessPrivate, QMetaType::Void, {{
+        QtMocHelpers::SlotData<void(int, const QPoint &)>(35, 2, QMC::AccessPrivate, QMetaType::Void, {{
             { QMetaType::Int, 3 }, { 0x80000000 | 10, 11 },
         }}),
         // Slot 'onCompactMailClicked'
-        QtMocHelpers::SlotData<void(int)>(26, 2, QMC::AccessPrivate, QMetaType::Void, {{
+        QtMocHelpers::SlotData<void(int)>(36, 2, QMC::AccessPrivate, QMetaType::Void, {{
             { QMetaType::Int, 3 },
         }}),
         // Slot 'onCompactReplyRequested'
-        QtMocHelpers::SlotData<void(int)>(27, 2, QMC::AccessPrivate, QMetaType::Void, {{
+        QtMocHelpers::SlotData<void(int)>(37, 2, QMC::AccessPrivate, QMetaType::Void, {{
             { QMetaType::Int, 3 },
         }}),
         // Slot 'onCompactForwardRequested'
-        QtMocHelpers::SlotData<void(int)>(28, 2, QMC::AccessPrivate, QMetaType::Void, {{
+        QtMocHelpers::SlotData<void(int)>(38, 2, QMC::AccessPrivate, QMetaType::Void, {{
             { QMetaType::Int, 3 },
         }}),
         // Slot 'onCompactMarkUnreadRequested'
-        QtMocHelpers::SlotData<void(int)>(29, 2, QMC::AccessPrivate, QMetaType::Void, {{
+        QtMocHelpers::SlotData<void(int)>(39, 2, QMC::AccessPrivate, QMetaType::Void, {{
             { QMetaType::Int, 3 },
         }}),
         // Slot 'onDisplayModeChanged'
-        QtMocHelpers::SlotData<void(int)>(30, 2, QMC::AccessPrivate, QMetaType::Void, {{
+        QtMocHelpers::SlotData<void(int)>(40, 2, QMC::AccessPrivate, QMetaType::Void, {{
-            { QMetaType::Int, 17 },
+            { QMetaType::Int, 27 },
         }}),
         // Slot 'onTotalCountChanged'
-        QtMocHelpers::SlotData<void(int)>(31, 2, QMC::AccessPrivate, QMetaType::Void, {{
+        QtMocHelpers::SlotData<void(int)>(41, 2, QMC::AccessPrivate, QMetaType::Void, {{
-            { QMetaType::Int, 32 },
+            { QMetaType::Int, 42 },
         }}),
         // Slot 'onTreeViewScrolled'
-        QtMocHelpers::SlotData<void(int)>(33, 2, QMC::AccessPrivate, QMetaType::Void, {{
+        QtMocHelpers::SlotData<void(int)>(43, 2, QMC::AccessPrivate, QMetaType::Void, {{
-            { QMetaType::Int, 34 },
+            { QMetaType::Int, 44 },
         }}),
         // Slot 'onListViewScrolled'
-        QtMocHelpers::SlotData<void(int)>(35, 2, QMC::AccessPrivate, QMetaType::Void, {{
+        QtMocHelpers::SlotData<void(int)>(45, 2, QMC::AccessPrivate, QMetaType::Void, {{
-            { QMetaType::Int, 34 },
+            { QMetaType::Int, 44 },
         }}),
         // Slot 'onRowsInserted'
-        QtMocHelpers::SlotData<void(const QModelIndex &, int, int)>(36, 2, QMC::AccessPrivate, QMetaType::Void, {{
+        QtMocHelpers::SlotData<void(const QModelIndex &, int, int)>(46, 2, QMC::AccessPrivate, QMetaType::Void, {{
-            { 0x80000000 | 16, 37 }, { QMetaType::Int, 38 }, { QMetaType::Int, 39 },
+            { 0x80000000 | 26, 47 }, { QMetaType::Int, 48 }, { QMetaType::Int, 49 },
         }}),
+        // Slot 'onSelectionChanged'
+        QtMocHelpers::SlotData<void()>(50, 2, QMC::AccessPrivate, QMetaType::Void),
+        // Slot 'onSelectAllToggled'
+        QtMocHelpers::SlotData<void(bool)>(51, 2, QMC::AccessPrivate, QMetaType::Void, {{
+            { QMetaType::Bool, 52 },
+        }}),
+        // Slot 'onBatchFlagClicked'
+        QtMocHelpers::SlotData<void()>(53, 2, QMC::AccessPrivate, QMetaType::Void),
+        // Slot 'onBatchMarkUnreadClicked'
+        QtMocHelpers::SlotData<void()>(54, 2, QMC::AccessPrivate, QMetaType::Void),
+        // Slot 'onBatchMoveClicked'
+        QtMocHelpers::SlotData<void()>(55, 2, QMC::AccessPrivate, QMetaType::Void),
+        // Slot 'onBatchDeleteClicked'
+        QtMocHelpers::SlotData<void()>(56, 2, QMC::AccessPrivate, QMetaType::Void),
+        // Slot 'enterMultiSelectMode'
+        QtMocHelpers::SlotData<void()>(57, 2, QMC::AccessPrivate, QMetaType::Void),
+        // Slot 'exitMultiSelectMode'
+        QtMocHelpers::SlotData<void()>(58, 2, QMC::AccessPrivate, QMetaType::Void),
     };
     QtMocHelpers::UintData qt_properties {
     };
@@ -219,26 +277,79 @@ void MailListView::qt_static_metacall(QObject *_o, QMetaObject::Call _c, int _id
         case 7: _t->replyRequested((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
         case 8: _t->forwardRequested((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
         case 9: _t->markUnreadRequested((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
-        case 10: _t->onRowSelected((*reinterpret_cast<std::add_pointer_t<QModelIndex>>(_a[1]))); break;
+        case 10: _t->selectionChanged((*reinterpret_cast<std::add_pointer_t<QList<int>>>(_a[1]))); break;
-        case 11: _t->onSearchTextChanged((*reinterpret_cast<std::add_pointer_t<QString>>(_a[1]))); break;
+        case 11: _t->batchFlagRequested((*reinterpret_cast<std::add_pointer_t<QList<int>>>(_a[1])),(*reinterpret_cast<std::add_pointer_t<bool>>(_a[2]))); break;
-        case 12: _t->onFilterChanged(); break;
+        case 12: _t->batchDeleteRequested((*reinterpret_cast<std::add_pointer_t<QList<int>>>(_a[1]))); break;
-        case 13: _t->onGroupByChanged((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
+        case 13: _t->batchMarkUnreadRequested((*reinterpret_cast<std::add_pointer_t<QList<int>>>(_a[1]))); break;
-        case 14: _t->onCompactFlagRequested((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
+        case 14: _t->batchMoveRequested((*reinterpret_cast<std::add_pointer_t<QList<int>>>(_a[1])),(*reinterpret_cast<std::add_pointer_t<int>>(_a[2]))); break;
-        case 15: _t->onCompactDeleteRequested((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
+        case 15: _t->onRowSelected((*reinterpret_cast<std::add_pointer_t<QModelIndex>>(_a[1]))); break;
-        case 16: _t->onCompactCategoryRequested((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
+        case 16: _t->onSearchTextChanged((*reinterpret_cast<std::add_pointer_t<QString>>(_a[1]))); break;
-        case 17: _t->onCompactMoreRequested((*reinterpret_cast<std::add_pointer_t<int>>(_a[1])),(*reinterpret_cast<std::add_pointer_t<QPoint>>(_a[2]))); break;
+        case 17: _t->onFilterChanged(); break;
-        case 18: _t->onCompactMailClicked((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
+        case 18: _t->onGroupByChanged((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
-        case 19: _t->onCompactReplyRequested((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
+        case 19: _t->onCompactFlagRequested((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
-        case 20: _t->onCompactForwardRequested((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
+        case 20: _t->onCompactDeleteRequested((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
-        case 21: _t->onCompactMarkUnreadRequested((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
+        case 21: _t->onCompactCategoryRequested((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
-        case 22: _t->onDisplayModeChanged((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
+        case 22: _t->onCompactMoreRequested((*reinterpret_cast<std::add_pointer_t<int>>(_a[1])),(*reinterpret_cast<std::add_pointer_t<QPoint>>(_a[2]))); break;
-        case 23: _t->onTotalCountChanged((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
+        case 23: _t->onCompactMailClicked((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
-        case 24: _t->onTreeViewScrolled((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
+        case 24: _t->onCompactReplyRequested((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
-        case 25: _t->onListViewScrolled((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
+        case 25: _t->onCompactForwardRequested((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
-        case 26: _t->onRowsInserted((*reinterpret_cast<std::add_pointer_t<QModelIndex>>(_a[1])),(*reinterpret_cast<std::add_pointer_t<int>>(_a[2])),(*reinterpret_cast<std::add_pointer_t<int>>(_a[3]))); break;
+        case 26: _t->onCompactMarkUnreadRequested((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
+        case 27: _t->onDisplayModeChanged((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
+        case 28: _t->onTotalCountChanged((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
+        case 29: _t->onTreeViewScrolled((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
+        case 30: _t->onListViewScrolled((*reinterpret_cast<std::add_pointer_t<int>>(_a[1]))); break;
+        case 31: _t->onRowsInserted((*reinterpret_cast<std::add_pointer_t<QModelIndex>>(_a[1])),(*reinterpret_cast<std::add_pointer_t<int>>(_a[2])),(*reinterpret_cast<std::add_pointer_t<int>>(_a[3]))); break;
+        case 32: _t->onSelectionChanged(); break;
+        case 33: _t->onSelectAllToggled((*reinterpret_cast<std::add_pointer_t<bool>>(_a[1]))); break;
+        case 34: _t->onBatchFlagClicked(); break;
+        case 35: _t->onBatchMarkUnreadClicked(); break;
+        case 36: _t->onBatchMoveClicked(); break;
+        case 37: _t->onBatchDeleteClicked(); break;
+        case 38: _t->enterMultiSelectMode(); break;
+        case 39: _t->exitMultiSelectMode(); break;
         default: ;
         }
     }
+    if (_c == QMetaObject::RegisterMethodArgumentMetaType) {
+        switch (_id) {
+        default: *reinterpret_cast<QMetaType *>(_a[0]) = QMetaType(); break;
+        case 10:
+            switch (*reinterpret_cast<int*>(_a[1])) {
+            default: *reinterpret_cast<QMetaType *>(_a[0]) = QMetaType(); break;
+            case 0:
+                *reinterpret_cast<QMetaType *>(_a[0]) = QMetaType::fromType< QList<int> >(); break;
+            }
+            break;
+        case 11:
+            switch (*reinterpret_cast<int*>(_a[1])) {
+            default: *reinterpret_cast<QMetaType *>(_a[0]) = QMetaType(); break;
+            case 0:
+                *reinterpret_cast<QMetaType *>(_a[0]) = QMetaType::fromType< QList<int> >(); break;
+            }
+            break;
+        case 12:
+            switch (*reinterpret_cast<int*>(_a[1])) {
+            default: *reinterpret_cast<QMetaType *>(_a[0]) = QMetaType(); break;
+            case 0:
+                *reinterpret_cast<QMetaType *>(_a[0]) = QMetaType::fromType< QList<int> >(); break;
+            }
+            break;
+        case 13:
+            switch (*reinterpret_cast<int*>(_a[1])) {
+            default: *reinterpret_cast<QMetaType *>(_a[0]) = QMetaType(); break;
+            case 0:
+                *reinterpret_cast<QMetaType *>(_a[0]) = QMetaType::fromType< QList<int> >(); break;
+            }
+            break;
+        case 14:
+            switch (*reinterpret_cast<int*>(_a[1])) {
+            default: *reinterpret_cast<QMetaType *>(_a[0]) = QMetaType(); break;
+            case 0:
+                *reinterpret_cast<QMetaType *>(_a[0]) = QMetaType::fromType< QList<int> >(); break;
+            }
+            break;
+        }
+    }
     if (_c == QMetaObject::IndexOfMethod) {
         if (QtMocHelpers::indexOfMethod<void (MailListView::*)(int )>(_a, &MailListView::emailSelected, 0))
             return;
@@ -260,6 +371,16 @@ void MailListView::qt_static_metacall(QObject *_o, QMetaObject::Call _c, int _id
             return;
         if (QtMocHelpers::indexOfMethod<void (MailListView::*)(int )>(_a, &MailListView::markUnreadRequested, 9))
             return;
+        if (QtMocHelpers::indexOfMethod<void (MailListView::*)(const QVector<int> & )>(_a, &MailListView::selectionChanged, 10))
+            return;
+        if (QtMocHelpers::indexOfMethod<void (MailListView::*)(const QVector<int> & , bool )>(_a, &MailListView::batchFlagRequested, 11))
+            return;
+        if (QtMocHelpers::indexOfMethod<void (MailListView::*)(const QVector<int> & )>(_a, &MailListView::batchDeleteRequested, 12))
+            return;
+        if (QtMocHelpers::indexOfMethod<void (MailListView::*)(const QVector<int> & )>(_a, &MailListView::batchMarkUnreadRequested, 13))
+            return;
+        if (QtMocHelpers::indexOfMethod<void (MailListView::*)(const QVector<int> & , int )>(_a, &MailListView::batchMoveRequested, 14))
+            return;
     }
 }
 
@@ -282,14 +403,14 @@ int MailListView::qt_metacall(QMetaObject::Call _c, int _id, void **_a)
     if (_id < 0)
         return _id;
     if (_c == QMetaObject::InvokeMetaMethod) {
-        if (_id < 27)
+        if (_id < 40)
             qt_static_metacall(this, _c, _id, _a);
-        _id -= 27;
+        _id -= 40;
     }
     if (_c == QMetaObject::RegisterMethodArgumentMetaType) {
-        if (_id < 27)
+        if (_id < 40)
-            *reinterpret_cast<QMetaType *>(_a[0]) = QMetaType();
+            qt_static_metacall(this, _c, _id, _a);
-        _id -= 27;
+        _id -= 40;
     }
     return _id;
 }
@@ -353,4 +474,34 @@ void MailListView::markUnreadRequested(int _t1)
 {
     QMetaObject::activate<void>(this, &staticMetaObject, 9, nullptr, _t1);
 }
+
+// SIGNAL 10
+void MailListView::selectionChanged(const QVector<int> & _t1)
+{
+    QMetaObject::activate<void>(this, &staticMetaObject, 10, nullptr, _t1);
+}
+
+// SIGNAL 11
+void MailListView::batchFlagRequested(const QVector<int> & _t1, bool _t2)
+{
+    QMetaObject::activate<void>(this, &staticMetaObject, 11, nullptr, _t1, _t2);
+}
+
+// SIGNAL 12
+void MailListView::batchDeleteRequested(const QVector<int> & _t1)
+{
+    QMetaObject::activate<void>(this, &staticMetaObject, 12, nullptr, _t1);
+}
+
+// SIGNAL 13
+void MailListView::batchMarkUnreadRequested(const QVector<int> & _t1)
+{
+    QMetaObject::activate<void>(this, &staticMetaObject, 13, nullptr, _t1);
+}
+
+// SIGNAL 14
+void MailListView::batchMoveRequested(const QVector<int> & _t1, int _t2)
+{
+    QMetaObject::activate<void>(this, &staticMetaObject, 14, nullptr, _t1, _t2);
+}
 QT_WARNING_POP

src/ui/maillistview.cpp

@@ -15,9 +15,11 @@
 #include <QListView>
 #include <QStyledItemDelegate>
 #include <QScrollBar>
+#include <QToolButton>
+#include <QMenu>
 #include "ui/delegates/CompactMailDelegate.h"
 
-MailListView::MailListView(QWidget *parent) : QWidget(parent), m_sourceModel(nullptr)
+MailListView::MailListView(QWidget *parent) : QWidget(parent), m_sourceModel(nullptr), m_multiSelectMode(false)
 {
     setupUI();
 }
@@ -110,6 +112,67 @@ void MailListView::setupUI()
 
     layout->addWidget(filterBar);
 
+    // Action bar (hidden by default, shown when multi-select mode active)
+    m_actionBar = new QWidget();
+    m_actionBar->setFixedHeight(44);
+    m_actionBar->setStyleSheet("background-color: #e3f2fd; border-bottom: 1px solid #bbdefb;");
+    m_actionBar->setVisible(false);
+    QHBoxLayout *actionBarLayout = new QHBoxLayout(m_actionBar);
+    actionBarLayout->setContentsMargins(12, 4, 12, 4);
+    actionBarLayout->setSpacing(8);
+
+    m_selectAllCheck = new QCheckBox("Seleccionar todo");
+    m_selectAllCheck->setStyleSheet("QCheckBox { font-size: 13px; color: #1d1d1f; }");
+    connect(m_selectAllCheck, &QCheckBox::toggled, this, &MailListView::onSelectAllToggled);
+    actionBarLayout->addWidget(m_selectAllCheck);
+
+    QLabel *selectionLabel = new QLabel("0 elementos seleccionados");
+    selectionLabel->setStyleSheet("font-size: 13px; color: #1d1d1f; font-weight: 500;");
+    selectionLabel->setObjectName("selectionLabel");
+    actionBarLayout->addWidget(selectionLabel);
+
+    actionBarLayout->addStretch();
+
+    // Action buttons
+    auto createActionButton = [&](const QString& text, std::function<void()> slot) -> QToolButton* {
+        QToolButton *btn = new QToolButton();
+        btn->setText(text);
+        btn->setToolButtonStyle(Qt::ToolButtonTextBesideIcon);
+        btn->setStyleSheet(
+            "QToolButton { background: white; border: 1px solid #d1d1d6; border-radius: 6px; "
+            "padding: 6px 12px; font-size: 12px; color: #1d1d1f; }"
+            "QToolButton:hover { background: #f0f0f5; border-color: #bdbdbd; }"
+            "QToolButton:pressed { background: #e0e0e5; }"
+        );
+        connect(btn, &QToolButton::clicked, this, slot);
+        return btn;
+    };
+
+    QToolButton *btnFlag = createActionButton("★ Marcar", [this]() { onBatchFlagClicked(); });
+    actionBarLayout->addWidget(btnFlag);
+
+    QToolButton *btnUnread = createActionButton("✎ No leído", [this]() { onBatchMarkUnreadClicked(); });
+    actionBarLayout->addWidget(btnUnread);
+
+    QToolButton *btnMove = createActionButton("↗ Mover", [this]() { onBatchMoveClicked(); });
+    actionBarLayout->addWidget(btnMove);
+
+    QToolButton *btnDelete = createActionButton("🗑 Borrar", [this]() { onBatchDeleteClicked(); });
+    btnDelete->setStyleSheet(btnDelete->styleSheet() + "QToolButton { color: #ff3b30; border-color: #ff3b30; }");
+    actionBarLayout->addWidget(btnDelete);
+
+    QToolButton *btnExit = new QToolButton();
+    btnExit->setText("✕ Salir selección");
+    btnExit->setToolButtonStyle(Qt::ToolButtonTextOnly);
+    btnExit->setStyleSheet(
+        "QToolButton { padding: 6px 12px; font-size: 12px; color: #0071e3; }"
+        "QToolButton:hover { background: #e8f0fe; border-radius: 6px; }"
+    );
+    connect(btnExit, &QToolButton::clicked, this, [this]() { exitMultiSelectMode(); });
+    actionBarLayout->addWidget(btnExit);
+
+    layout->insertWidget(1, m_actionBar); // Insert after search bar
+
     // View Stack (TreeView for normal, ListView for compact)
     m_viewStack = new QStackedWidget();
     layout->addWidget(m_viewStack, 1);
@@ -117,7 +180,7 @@ void MailListView::setupUI()
     // --- Normal Tree View ---
     m_treeView = new QTreeView();
     m_treeView->setSelectionBehavior(QAbstractItemView::SelectRows);
-    m_treeView->setSelectionMode(QAbstractItemView::SingleSelection);
+    m_treeView->setSelectionMode(QAbstractItemView::ExtendedSelection); // Multi-selection
     m_treeView->setAlternatingRowColors(true);
     m_treeView->header()->setStretchLastSection(false);
     m_treeView->header()->setSectionsClickable(true);
@@ -146,7 +209,8 @@ void MailListView::setupUI()
     m_treeView->header()->setSectionResizeMode(EmailTreeModel::ColSender, QHeaderView::Stretch);
     m_treeView->header()->setSectionResizeMode(EmailTreeModel::ColDate, QHeaderView::ResizeToContents);
 
-    connect(m_treeView, &QTreeView::clicked, this, &MailListView::onRowSelected);
+    connect(m_treeView->selectionModel(), &QItemSelectionModel::selectionChanged,
+            this, &MailListView::onSelectionChanged);
     connect(m_treeView, &QTreeView::doubleClicked, this, [this](const QModelIndex &index) {
         if (!index.isValid()) return;
         QModelIndex proxyIdx = m_proxyModel->mapToSource(index);
@@ -172,7 +236,7 @@ void MailListView::setupUI()
 
     // --- Compact List View ---
     m_listView = new QListView();
-    m_listView->setSelectionMode(QAbstractItemView::SingleSelection);
+    m_listView->setSelectionMode(QAbstractItemView::ExtendedSelection); // Multi-selection
     m_listView->setUniformItemSizes(true);
     m_listView->setFrameShape(QFrame::NoFrame);
     m_listView->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
@@ -197,11 +261,20 @@ void MailListView::setupUI()
             this, &MailListView::onCompactMoreRequested);
     connect(m_compactDelegate, &CompactMailDelegate::mailClicked,
             this, &MailListView::onCompactMailClicked);
+    connect(m_compactDelegate, &CompactMailDelegate::replyRequested,
+            this, &MailListView::onCompactReplyRequested);
+    connect(m_compactDelegate, &CompactMailDelegate::forwardRequested,
+            this, &MailListView::onCompactForwardRequested);
+    connect(m_compactDelegate, &CompactMailDelegate::markUnreadRequested,
+            this, &MailListView::onCompactMarkUnreadRequested);
 
     // Same proxy model for list view (single column)
     m_listView->setModel(m_proxyModel);
     m_listView->setModelColumn(0); // Use first column (subject)
 
+    connect(m_listView->selectionModel(), &QItemSelectionModel::selectionChanged,
+            this, &MailListView::onSelectionChanged);
+
     // Add both views to stack
     m_viewStack->addWidget(m_treeView);  // index 0 = normal
     m_viewStack->addWidget(m_listView);  // index 1 = compact
@@ -271,13 +344,82 @@ void MailListView::updateViewMode()
     }
 }
 
-void MailListView::onRowSelected(const QModelIndex &index)
+QVector<int> MailListView::getSelectedMailIds() const
 {
-    if (!index.isValid()) return;
+    QVector<int> mailIds;
-    QModelIndex proxyIdx = m_proxyModel->mapToSource(index);
+    QAbstractItemView *currentView = qobject_cast<QAbstractItemView*>(m_viewStack->currentWidget());
-    if (proxyIdx.isValid() && proxyIdx.data(EmailTreeModel::MailIdRole).isValid()) {
+    QItemSelectionModel *selectionModel = currentView->selectionModel();
-        int mailId = proxyIdx.data(EmailTreeModel::MailIdRole).toInt();
+
-        emit emailSelected(mailId);
+    if (!selectionModel) return mailIds;
+
+    QModelIndexList selectedIndexes = selectionModel->selectedRows();
+    for (const QModelIndex &proxyIdx : selectedIndexes) {
+        QModelIndex sourceIdx = m_proxyModel->mapToSource(proxyIdx);
+        if (sourceIdx.isValid() && sourceIdx.data(EmailTreeModel::MailIdRole).isValid()) {
+            int mailId = sourceIdx.data(EmailTreeModel::MailIdRole).toInt();
+            mailIds.append(mailId);
+        }
+    }
+    return mailIds;
+}
+
+void MailListView::updateActionBar()
+{
+    QLabel *label = m_actionBar->findChild<QLabel*>("selectionLabel");
+    if (label) {
+        label->setText(QString("%1 elementos seleccionados").arg(m_selectedMailIds.size()));
+    }
+
+    m_selectAllCheck->blockSignals(true);
+    m_selectAllCheck->setChecked(m_selectedMailIds.size() > 0);
+    m_selectAllCheck->blockSignals(false);
+}
+
+void MailListView::onSelectionChanged()
+{
+    m_selectedMailIds = getSelectedMailIds();
+    bool hasSelection = !m_selectedMailIds.isEmpty();
+
+    if (hasSelection && !m_multiSelectMode) {
+        enterMultiSelectMode();
+    } else if (!hasSelection && m_multiSelectMode) {
+        exitMultiSelectMode();
+    }
+
+    updateActionBar();
+    emit selectionChanged(m_selectedMailIds);
+}
+
+void MailListView::enterMultiSelectMode()
+{
+    m_multiSelectMode = true;
+    m_actionBar->setVisible(true);
+    updateActionBar();
+}
+
+void MailListView::exitMultiSelectMode()
+{
+    m_multiSelectMode = false;
+    m_selectedMailIds.clear();
+    m_actionBar->setVisible(false);
+
+    // Clear selections
+    m_treeView->clearSelection();
+    m_listView->clearSelection();
+    m_selectAllCheck->blockSignals(true);
+    m_selectAllCheck->setChecked(false);
+    m_selectAllCheck->blockSignals(false);
+    updateActionBar();
+    emit selectionChanged(QVector<int>());
+}
+
+void MailListView::onSelectAllToggled(bool checked)
+{
+    QAbstractItemView *currentView = qobject_cast<QAbstractItemView*>(m_viewStack->currentWidget());
+    if (checked) {
+        currentView->selectAll();
+    } else {
+        currentView->clearSelection();
     }
 }
 
@@ -314,46 +456,6 @@ void MailListView::onGroupByChanged(int index)
     m_treeView->expandAll();
 }
 
-void MailListView::onCompactFlagRequested(int mailId)
-{
-    emit flagRequested(mailId);
-}
-
-void MailListView::onCompactDeleteRequested(int mailId)
-{
-    emit deleteRequested(mailId);
-}
-
-void MailListView::onCompactCategoryRequested(int mailId)
-{
-    emit categoryRequested(mailId);
-}
-
-void MailListView::onCompactMoreRequested(int mailId, const QPoint &globalPos)
-{
-    emit moreRequested(mailId, globalPos);
-}
-
-void MailListView::onCompactMailClicked(int mailId)
-{
-    emit emailSelected(mailId);
-}
-
-void MailListView::onCompactReplyRequested(int mailId)
-{
-    emit replyRequested(mailId);
-}
-
-void MailListView::onCompactForwardRequested(int mailId)
-{
-    emit forwardRequested(mailId);
-}
-
-void MailListView::onCompactMarkUnreadRequested(int mailId)
-{
-    emit markUnreadRequested(mailId);
-}
-
 void MailListView::onDisplayModeChanged(int index)
 {
     CompactMailDelegate::DisplayMode mode = static_cast<CompactMailDelegate::DisplayMode>(index);
@@ -399,3 +501,84 @@ void MailListView::onRowsInserted(const QModelIndex &parent, int first, int last
         m_treeView->expandAll();
     }
 }
+
+void MailListView::onRowSelected(const QModelIndex &index)
+{
+    if (!index.isValid()) return;
+    QModelIndex proxyIdx = m_proxyModel->mapToSource(index);
+    if (proxyIdx.isValid() && proxyIdx.data(EmailTreeModel::MailIdRole).isValid()) {
+        int mailId = proxyIdx.data(EmailTreeModel::MailIdRole).toInt();
+        emit emailSelected(mailId);
+    }
+}
+
+void MailListView::onCompactFlagRequested(int mailId)
+{
+    emit flagRequested(mailId);
+}
+
+void MailListView::onCompactDeleteRequested(int mailId)
+{
+    emit deleteRequested(mailId);
+}
+
+void MailListView::onCompactCategoryRequested(int mailId)
+{
+    emit categoryRequested(mailId);
+}
+
+void MailListView::onCompactMoreRequested(int mailId, const QPoint &globalPos)
+{
+    emit moreRequested(mailId, globalPos);
+}
+
+void MailListView::onCompactMailClicked(int mailId)
+{
+    emit emailSelected(mailId);
+}
+
+void MailListView::onCompactReplyRequested(int mailId)
+{
+    emit replyRequested(mailId);
+}
+
+void MailListView::onCompactForwardRequested(int mailId)
+{
+    emit forwardRequested(mailId);
+}
+
+void MailListView::onCompactMarkUnreadRequested(int mailId)
+{
+    emit markUnreadRequested(mailId);
+}
+
+// Batch action slots
+void MailListView::onBatchFlagClicked()
+{
+    if (m_selectedMailIds.isEmpty()) return;
+    emit batchFlagRequested(m_selectedMailIds, true);
+    exitMultiSelectMode();
+}
+
+void MailListView::onBatchMarkUnreadClicked()
+{
+    if (m_selectedMailIds.isEmpty()) return;
+    emit batchMarkUnreadRequested(m_selectedMailIds);
+    exitMultiSelectMode();
+}
+
+void MailListView::onBatchMoveClicked()
+{
+    if (m_selectedMailIds.isEmpty()) return;
+    // TODO: Show folder picker dialog
+    // For now, just emit signal
+    // emit batchMoveRequested(m_selectedMailIds, targetFolderId);
+    exitMultiSelectMode();
+}
+
+void MailListView::onBatchDeleteClicked()
+{
+    if (m_selectedMailIds.isEmpty()) return;
+    emit batchDeleteRequested(m_selectedMailIds);
+    exitMultiSelectMode();
+}

src/ui/maillistview.h

@@ -41,6 +41,12 @@ signals:
     void replyRequested(int mailId);
     void forwardRequested(int mailId);
     void markUnreadRequested(int mailId);
+    // Multi-selection signals
+    void selectionChanged(const QVector<int>& selectedMailIds);
+    void batchFlagRequested(const QVector<int>& mailIds, bool flagged);
+    void batchDeleteRequested(const QVector<int>& mailIds);
+    void batchMarkUnreadRequested(const QVector<int>& mailIds);
+    void batchMoveRequested(const QVector<int>& mailIds, int targetFolderId);
 
 private slots:
     void onRowSelected(const QModelIndex &index);
@@ -60,6 +66,14 @@ private slots:
     void onTreeViewScrolled(int value);
     void onListViewScrolled(int value);
     void onRowsInserted(const QModelIndex &parent, int first, int last);
+    void onSelectionChanged();
+    void onSelectAllToggled(bool checked);
+    void onBatchFlagClicked();
+    void onBatchMarkUnreadClicked();
+    void onBatchMoveClicked();
+    void onBatchDeleteClicked();
+    void enterMultiSelectMode();
+    void exitMultiSelectMode();
 
 protected:
     void resizeEvent(QResizeEvent *event) override;
@@ -68,6 +82,8 @@ private:
     void setupUI();
     void refreshViews();
     void updateViewMode();
+    void updateActionBar();
+    QVector<int> getSelectedMailIds() const;
 
     QTreeView *m_treeView;
     QListView *m_listView;
@@ -81,9 +97,13 @@ private:
     QCheckBox *m_flaggedOnlyCheck;
     QCheckBox *m_hasAttachmentsCheck;
     QCheckBox *m_pinnedOnlyCheck;
+    QCheckBox *m_selectAllCheck;  // Select all checkbox in action bar
+    QWidget *m_actionBar;  // Action bar widget
     QComboBox *m_groupByCombo;
     QComboBox *m_displayModeCombo;
     CompactMailDelegate *m_compactDelegate = nullptr;
     bool m_compactMode = false;
     int m_compactThreshold = 650;
+    bool m_multiSelectMode = false;
+    QVector<int> m_selectedMailIds;
 };