src/animatedheightwidget.cpp

   1 /*
   2     This file is part of the KDE project
   3     SPDX-FileCopyrightText: 2024 Felix Ernst <felixernst@kde.org>
   4
   5     SPDX-License-Identifier: LGPL-2.1-only OR LGPL-3.0-only OR LicenseRef-KDE-Accepted-LGPL
   6 */
   7
   8 #include "animatedheightwidget.h"
   9
  10 #include <QGridLayout>
  11 #include <QPropertyAnimation>
  12 #include <QScrollArea>
  13 #include <QScrollBar>
  14 #include <QStyle>
  15
  16 AnimatedHeightWidget::AnimatedHeightWidget(QWidget *parent)
  17     : QWidget{parent}
  18 {
  19     // Showing of this widget is normally animated. We hide it for now and make it small.
  20     hide();
  21     setMaximumHeight(0);
  22
  23     auto fillParentLayout = new QGridLayout(this);
  24     fillParentLayout->setContentsMargins(0, 0, 0, 0);
  25
  26     // Put the contents into a QScrollArea. This prevents increasing the view width
  27     // in case there is not enough available width for the contents.
  28     m_contentsContainerParent = new QScrollArea(this);
  29     fillParentLayout->addWidget(m_contentsContainerParent);
  30     m_contentsContainerParent->setFrameShape(QFrame::NoFrame);
  31     m_contentsContainerParent->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
  32     m_contentsContainerParent->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
  33     m_contentsContainerParent->setWidgetResizable(true);
  34     // Disables manual scrolling, for example with mouse scrollwheel.
  35     m_contentsContainerParent->verticalScrollBar()->setEnabled(false);
  36     m_contentsContainerParent->horizontalScrollBar()->setEnabled(false);
  37
  38     setMinimumWidth(0);
  39 }
  40
  41 QSize AnimatedHeightWidget::sizeHint() const
  42 {
  43     return QSize{1, preferredHeight()};
  44     // 1 as width because this widget should never be the reason the DolphinViewContainer is made wider.
  45 }
  46
  47 void AnimatedHeightWidget::setVisible(bool visible, Animated animated)
  48 {
  49     setEnabled(visible);
  50     if (m_heightAnimation) {
  51         m_heightAnimation->stop(); // deletes because of QAbstractAnimation::DeleteWhenStopped.
  52     }
  53
  54     if (animated == WithAnimation
  55         && (style()->styleHint(QStyle::SH_Widget_Animation_Duration, nullptr, this) < 1 || GlobalConfig::animationDurationFactor() <= 0.0)) {
  56         animated = WithoutAnimation;
  57     }
  58
  59     if (animated == WithoutAnimation) {
  60         setMaximumHeight(visible ? preferredHeight() : 0);
  61         setVisible(visible);
  62         return;
  63     }
  64
  65     m_heightAnimation = new QPropertyAnimation(this, "maximumHeight");
  66     m_heightAnimation->setDuration(2 * style()->styleHint(QStyle::SH_Widget_Animation_Duration, nullptr, this) * GlobalConfig::animationDurationFactor());
  67
  68     m_heightAnimation->setStartValue(height());
  69     m_heightAnimation->setEasingCurve(QEasingCurve::OutCubic);
  70     if (visible) {
  71         show();
  72         m_heightAnimation->setEndValue(preferredHeight());
  73     } else {
  74         m_heightAnimation->setEndValue(0);
  75         connect(m_heightAnimation, &QAbstractAnimation::finished, this, &QWidget::hide);
  76     }
  77
  78     m_heightAnimation->start(QAbstractAnimation::DeleteWhenStopped);
  79 }
  80
  81 QWidget *AnimatedHeightWidget::prepareContentsContainer(QWidget *contentsContainer)
  82 {
  83     Q_ASSERT_X(!m_contentsContainerParent->widget(),
  84                "AnimatedHeightWidget::prepareContentsContainer",
  85                "Another contentsContainer has already been prepared. There can only be one.");
  86     contentsContainer->setParent(m_contentsContainerParent);
  87     m_contentsContainerParent->setWidget(contentsContainer);
  88     m_contentsContainerParent->setFocusProxy(contentsContainer);
  89     return contentsContainer;
  90 }
  91
  92 bool AnimatedHeightWidget::isAnimationRunning() const
  93 {
  94     return m_heightAnimation && m_heightAnimation->state() == QAbstractAnimation::Running;
  95 }