Qt: Add CollapsibleWidget

src/duckstation-qt/collapsiblewidget.cpp

@@ -0,0 +1,56 @@
+#include <QtCore/QPropertyAnimation>
+
+#include "collapsiblewidget.h"
+
+CollapsibleWidget::CollapsibleWidget(const QString& title, const int animationDuration, QWidget* parent)
+  : QWidget(parent), animationDuration(animationDuration)
+{
+  toggleButton.setStyleSheet("QToolButton { border: none; }");
+  toggleButton.setToolButtonStyle(Qt::ToolButtonTextBesideIcon);
+  toggleButton.setArrowType(Qt::ArrowType::RightArrow);
+  toggleButton.setText(title);
+  toggleButton.setCheckable(true);
+  toggleButton.setChecked(false);
+
+  contentArea.setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Fixed);
+
+  // start out collapsed
+  contentArea.setMaximumHeight(0);
+  contentArea.setMinimumHeight(0);
+
+  // let the entire widget grow and shrink with its content
+  toggleAnimation.addAnimation(new QPropertyAnimation(this, "minimumHeight"));
+  toggleAnimation.addAnimation(new QPropertyAnimation(this, "maximumHeight"));
+  toggleAnimation.addAnimation(new QPropertyAnimation(&contentArea, "maximumHeight"));
+
+  // don't waste space
+  mainLayout.setContentsMargins(0, 0, 0, 0);
+  mainLayout.addWidget(&toggleButton);
+  mainLayout.addWidget(&contentArea);
+  setLayout(&mainLayout);
+  QObject::connect(&toggleButton, &QToolButton::clicked, [this](const bool checked) {
+    toggleButton.setArrowType(checked ? Qt::ArrowType::DownArrow : Qt::ArrowType::RightArrow);
+    toggleAnimation.setDirection(checked ? QAbstractAnimation::Forward : QAbstractAnimation::Backward);
+    toggleAnimation.start();
+  });
+}
+
+void CollapsibleWidget::setContentLayout(QLayout* contentLayout)
+{
+  delete contentArea.layout();
+  contentArea.setLayout(contentLayout);
+  const auto collapsedHeight = sizeHint().height() - contentArea.maximumHeight();
+  auto contentHeight = contentLayout->sizeHint().height();
+  for (int i = 0; i < toggleAnimation.animationCount() - 1; ++i)
+  {
+    QPropertyAnimation* spoilerAnimation = static_cast<QPropertyAnimation*>(toggleAnimation.animationAt(i));
+    spoilerAnimation->setDuration(animationDuration);
+    spoilerAnimation->setStartValue(collapsedHeight);
+    spoilerAnimation->setEndValue(collapsedHeight + contentHeight);
+  }
+  QPropertyAnimation* contentAnimation =
+    static_cast<QPropertyAnimation*>(toggleAnimation.animationAt(toggleAnimation.animationCount() - 1));
+  contentAnimation->setDuration(animationDuration);
+  contentAnimation->setStartValue(0);
+  contentAnimation->setEndValue(contentHeight);
+}