From d174307bce717ef2467ff1b2d32bf68b9f3a912b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lukas=20Br=C3=BCbach?= <Bruebach.Lukas@bdosecurity.de>
Date: Sat, 19 Sep 2026 07:23:56 +0200
Subject: [PATCH] [DeckShare] Keep arrow-key navigation between flow items
 inside a scroll area

---
 .../general/layout_containers/flow_widget.cpp | 31 ++++++++++++++++---
 .../general/layout_containers/flow_widget.h   |  7 ++++-
 2 files changed, 32 insertions(+), 6 deletions(-)

diff --git a/cockatrice/src/interface/widgets/general/layout_containers/flow_widget.cpp b/cockatrice/src/interface/widgets/general/layout_containers/flow_widget.cpp
index 6e04fed5a..05dcf3e8e 100644
--- a/cockatrice/src/interface/widgets/general/layout_containers/flow_widget.cpp
+++ b/cockatrice/src/interface/widgets/general/layout_containers/flow_widget.cpp
@@ -81,10 +81,15 @@ FlowWidget::FlowWidget(QWidget *parent,
 /**
  * @brief Adds a widget to the flow layout within the FlowWidget.
  *
+ * The widget is filtered for arrow-key events so keyboard navigation between
+ * the flow items keeps working even when the flow sits inside a QScrollArea,
+ * which swallows arrow keys before they can reach FlowWidget::keyPressEvent.
+ *
  * @param widget_to_add The widget to add to the flow layout.
  */
-void FlowWidget::addWidget(QWidget *widget_to_add) const
+void FlowWidget::addWidget(QWidget *widget_to_add)
 {
+    widget_to_add->installEventFilter(this);
     flowLayout->addWidget(widget_to_add);
 }
 
@@ -179,6 +184,23 @@ QLayoutItem *FlowWidget::itemAt(int index) const
 }
 
 void FlowWidget::keyPressEvent(QKeyEvent *event)
+{
+    if (moveFocus(event)) {
+        event->accept();
+        return;
+    }
+    QWidget::keyPressEvent(event);
+}
+
+bool FlowWidget::eventFilter(QObject *watched, QEvent *event)
+{
+    if (event->type() == QEvent::KeyPress && moveFocus(static_cast<QKeyEvent *>(event))) {
+        return true;
+    }
+    return QWidget::eventFilter(watched, event);
+}
+
+bool FlowWidget::moveFocus(QKeyEvent *event)
 {
     // Keyboard navigation between the flow items: arrow keys move focus just
     // like clicking the sibling tiles would. Only items that can take keyboard
@@ -186,8 +208,7 @@ void FlowWidget::keyPressEvent(QKeyEvent *event)
     const bool moveForward = event->key() == Qt::Key_Right || event->key() == Qt::Key_Down;
     const bool moveBackward = event->key() == Qt::Key_Left || event->key() == Qt::Key_Up;
     if (!moveForward && !moveBackward) {
-        QWidget::keyPressEvent(event);
-        return;
+        return false;
     }
 
     QList<QWidget *> focusableItems;
@@ -199,8 +220,7 @@ void FlowWidget::keyPressEvent(QKeyEvent *event)
     }
 
     if (focusableItems.isEmpty()) {
-        QWidget::keyPressEvent(event);
-        return;
+        return false;
     }
 
     int currentIndex = -1;
@@ -220,6 +240,7 @@ void FlowWidget::keyPressEvent(QKeyEvent *event)
     }
     focusableItems.value(nextIndex)->setFocus();
     event->accept();
+    return true;
 }
 
 int FlowWidget::count() const
diff --git a/cockatrice/src/interface/widgets/general/layout_containers/flow_widget.h b/cockatrice/src/interface/widgets/general/layout_containers/flow_widget.h
index 3f3a2be2b..bdcb1e590 100644
--- a/cockatrice/src/interface/widgets/general/layout_containers/flow_widget.h
+++ b/cockatrice/src/interface/widgets/general/layout_containers/flow_widget.h
@@ -29,7 +29,7 @@ public:
                Qt::ScrollBarPolicy horizontalPolicy,
                Qt::ScrollBarPolicy verticalPolicy);
 
-    void addWidget(QWidget *widget_to_add) const;
+    void addWidget(QWidget *widget_to_add);
     void insertWidgetAtIndex(QWidget *toInsert, int index);
     void removeWidget(QWidget *widgetToRemove) const;
     void clearLayout();
@@ -44,10 +44,15 @@ public slots:
     void setSpacing(int hSpacing, int vSpacing);
 
 protected:
+    bool eventFilter(QObject *watched, QEvent *event) override;
     void resizeEvent(QResizeEvent *event) override;
     void keyPressEvent(QKeyEvent *event) override;
 
 private:
+    /// @brief Moves keyboard focus to an adjacent flow item for an arrow-key event.
+    /// @return True when the event was an arrow key and was handled.
+    bool moveFocus(QKeyEvent *event);
+
     Qt::Orientation flowDirection;
     QHBoxLayout *mainLayout;
     FlowLayout *flowLayout;