Add transparent overlay window (#4746)

src/widgets/helper/OverlayInteraction.cpp

@@ -0,0 +1,123 @@
+#include "widgets/helper/OverlayInteraction.hpp"
+
+#include "common/Literals.hpp"
+#include "widgets/OverlayWindow.hpp"
+
+#include <QGridLayout>
+
+namespace chatterino {
+
+using namespace literals;
+
+OverlayInteraction::OverlayInteraction(OverlayWindow *parent)
+    : QWidget(nullptr)
+    , interactAnimation_(this, "interactionProgress"_ba)
+    , window_(parent)
+{
+    this->interactAnimation_.setStartValue(0.0);
+    this->interactAnimation_.setEndValue(1.0);
+
+    this->closeButton_.setButtonStyle(TitleBarButtonStyle::Close);
+    this->closeButton_.setScaleIndependantSize(46, 30);
+    this->closeButton_.hide();
+    this->closeButton_.setCursor(Qt::PointingHandCursor);
+}
+
+void OverlayInteraction::attach(QGridLayout *layout)
+{
+    layout->addWidget(this, 0, 0);
+    layout->addWidget(&this->closeButton_, 0, 0, Qt::AlignTop | Qt::AlignRight);
+    layout->setContentsMargins(0, 0, 0, 0);
+
+    QObject::connect(&this->closeButton_, &TitleBarButton::leftClicked,
+                     [this]() {
+                         this->window_->close();
+                     });
+}
+
+QWidget *OverlayInteraction::closeButton()
+{
+    return &this->closeButton_;
+}
+
+void OverlayInteraction::startInteraction()
+{
+    if (this->interacting_)
+    {
+        return;
+    }
+
+    this->interacting_ = true;
+    if (this->interactAnimation_.state() != QPropertyAnimation::Stopped)
+    {
+        this->interactAnimation_.stop();
+    }
+    this->interactAnimation_.setDirection(QPropertyAnimation::Forward);
+    this->interactAnimation_.setDuration(100);
+    this->interactAnimation_.start();
+    this->window_->setOverrideCursor(Qt::SizeAllCursor);
+    this->closeButton_.show();
+}
+
+void OverlayInteraction::endInteraction()
+{
+    if (!this->interacting_)
+    {
+        return;
+    }
+
+    this->interacting_ = false;
+    if (this->interactAnimation_.state() != QPropertyAnimation::Stopped)
+    {
+        this->interactAnimation_.stop();
+    }
+    this->interactAnimation_.setDirection(QPropertyAnimation::Backward);
+    this->interactAnimation_.setDuration(200);
+    this->interactAnimation_.start();
+    this->window_->setOverrideCursor(Qt::ArrowCursor);
+    this->closeButton_.hide();
+}
+
+bool OverlayInteraction::isInteracting() const
+{
+    return this->interacting_;
+}
+
+void OverlayInteraction::paintEvent(QPaintEvent * /*event*/)
+{
+    QPainter painter(this);
+    QColor highlightColor(
+        255, 255, 255, std::max(int(255.0 * this->interactionProgress()), 50));
+
+    painter.setPen({highlightColor, 2});
+    // outline
+    auto bounds = this->rect();
+    painter.drawRect(bounds);
+
+    if (this->interactionProgress() <= 0.0)
+    {
+        return;
+    }
+
+    highlightColor.setAlpha(highlightColor.alpha() / 4);
+    painter.setBrush(highlightColor);
+    painter.setPen(Qt::transparent);
+
+    // close button
+    auto buttonSize = this->closeButton_.size();
+    painter.drawRect(
+        QRect{bounds.topRight() - QPoint{buttonSize.width(), 0}, buttonSize});
+}
+
+double OverlayInteraction::interactionProgress() const
+{
+    return this->interactionProgress_;
+}
+
+void OverlayInteraction::setInteractionProgress(double progress)
+{
+    this->interactionProgress_ = progress;
+    this->update();
+}
+
+}  // namespace chatterino