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diff --git a/src/animatedheightwidget.h b/src/animatedheightwidget.h
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+++ b/src/animatedheightwidget.h
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+/*
+    This file is part of the KDE project
+    SPDX-FileCopyrightText: 2024 Felix Ernst <[email protected]>
+
+    SPDX-License-Identifier: LGPL-2.1-only OR LGPL-3.0-only OR LicenseRef-KDE-Accepted-LGPL
+*/
+
+#ifndef ANIMATEDHEIGHTWIDGET_H
+#define ANIMATEDHEIGHTWIDGET_H
+
+#include "global.h"
+
+#include <QPointer>
+#include <QWidget>
+
+class QPropertyAnimation;
+class QScrollArea;
+
+/**
+ * @brief An abstract base class which facilitates animated showing and hiding of sub-classes
+ */
+class AnimatedHeightWidget : public QWidget
+{
+public:
+    AnimatedHeightWidget(QWidget *parent);
+
+    /**
+     * Plays a show or hide animation while changing visibility.
+     * Therefore, if this method is used to hide this widget, the actual hiding will be delayed until the animation finished.
+     *
+     * @param visible   Whether this bar is supposed to be visible long-term
+     * @param animated  Whether this should be animated. The animation is skipped if the users' settings are configured that way.
+     *
+     * @see QWidget::setVisible()
+     */
+    void setVisible(bool visible, Animated animated);
+
+    /**
+     * @returns a QSize with a width of 1 to make sure that this bar never causes side panels to shrink.
+     *          The returned height equals preferredHeight().
+     */
+    QSize sizeHint() const override;
+
+protected:
+    /**
+     * AnimatedHeightWidget always requires a singular main child which we call the "contentsContainer".
+     * Use this method to register such an object.
+     *
+     * @returns a "contentsContainer" which is a QWidget that consists of/contains all visible contents of this AnimatedHeightWidget.
+     *          It will be the only grandchild of this AnimatedHeightWidget.
+     * @param contentsContainer The object that should be used as the "contentsContainer".
+     */
+    QWidget *prepareContentsContainer(QWidget *contentsContainer = new QWidget);
+
+    /** @returns whether this object is currently animating a visibility change. */
+    bool isAnimationRunning() const;
+
+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.
+    using QWidget::show; // Use QAbstractAnimation::setVisible() instead.
+
+    /** @returns the full preferred height this widget should have when it is done animating and visible. */
+    virtual int preferredHeight() const = 0;
+
+private:
+    /** @see contentsContainerParent() */
+    QScrollArea *m_contentsContainerParent = nullptr;
+
+    /** @see AnimatedHeightWidget::setVisible() */
+    QPointer<QPropertyAnimation> m_heightAnimation;
+};
+
+#endif // ANIMATEDHEIGHTWIDGET_H