animatedheightwidget: ignore PageUp/PageDown to avoid invisible scroll

When typing in the search bar (or other widgets using AnimatedHeightWidget), pressing PageUp or PageDown would cause the internal QScrollArea (with hidden scrollbars) to react and scroll. This made the entered text appear to disappear even though focus stayed in the input field. PageUp and PageDown are now intercepted in AnimatedHeightWidget to prevent the underlying QScrollArea from handling them, ensuring input remains visible across all users of AnimatedHeightWidget.

BUG: 508835

2 files changed, 23 insertions, 0 deletions

diff --git a/src/animatedheightwidget.cpp b/src/animatedheightwidget.cpp
index cd62f3971..c89863b25 100644
--- a/src/animatedheightwidget.cpp
+++ b/src/animatedheightwidget.cpp
@@ -7,7 +7,9 @@
 
 #include "animatedheightwidget.h"
 
+#include <QEvent>
 #include <QGridLayout>
+#include <QKeyEvent>
 #include <QPropertyAnimation>
 #include <QScrollArea>
 #include <QScrollBar>
@@ -86,6 +88,7 @@ QWidget *AnimatedHeightWidget::prepareContentsContainer(QWidget *contentsContain
     contentsContainer->setParent(m_contentsContainerParent);
     m_contentsContainerParent->setWidget(contentsContainer);
     m_contentsContainerParent->setFocusProxy(contentsContainer);
+    contentsContainer->installEventFilter(this);
     return contentsContainer;
 }
 
@@ -93,3 +96,16 @@ bool AnimatedHeightWidget::isAnimationRunning() const
 {
     return m_heightAnimation && m_heightAnimation->state() == QAbstractAnimation::Running;
 }
+
+bool AnimatedHeightWidget::eventFilter(QObject *obj, QEvent *event)
+{
+    if (event->type() == QEvent::KeyPress) {
+        auto *keyEvent = static_cast<QKeyEvent *>(event);
+        // Ignore PageUp/PageDown to prevent QScrollArea (invisible scrollbar) from scrolling
+        if (keyEvent->key() == Qt::Key_PageUp || keyEvent->key() == Qt::Key_PageDown) {
+            keyEvent->accept();
+            return true;
+        }
+    }
+    return QWidget::eventFilter(obj, event);
+}
\ No newline at end of file
diff --git a/src/animatedheightwidget.h b/src/animatedheightwidget.h
index 8f040d571..3933df93f 100644
--- a/src/animatedheightwidget.h
+++ b/src/animatedheightwidget.h
@@ -55,6 +55,13 @@ protected:
     /** @returns whether this object is currently animating a visibility change. */
     bool isAnimationRunning() const;
 
+protected:
+    /**
+     * Ignore PageUp/PageDown key events to prevent the internal QScrollArea
+     * (with an invisible scrollbar) from scrolling while editing inside child widgets.
+     */
+    bool eventFilter(QObject *obj, QEvent *event) override;
+
 private:
     using QWidget::hide; // Use QAbstractAnimation::setVisible() instead.
     using QWidget::setVisible; // Makes sure that the setVisible() declaration above doesn't fully hide the one from QWidget so we can still use it privately.