popups: add popup windows

src/core/popupwindow.hpp

@@ -0,0 +1,102 @@
+#pragma once
+
+#include <qobject.h>
+#include <qqmlintegration.h>
+#include <qquickwindow.h>
+#include <qtmetamacros.h>
+#include <qtypes.h>
+
+#include "doc.hpp"
+#include "proxywindow.hpp"
+#include "qmlscreen.hpp"
+#include "windowinterface.hpp"
+
+///! Popup window.
+/// Popup window that can display in a position relative to a floating
+/// or panel window.
+///
+/// #### Example
+/// The following snippet creates a panel with a popup centered over it.
+///
+/// ```qml
+/// PanelWindow {
+///   id: toplevel
+///
+///   anchors {
+///     bottom: true
+///     left: true
+///     right: true
+///   }
+///
+///   PopupWindow {
+///     parentWindow: toplevel
+///     relativeX: parentWindow.width / 2 - width / 2
+///     relativeY: parentWindow.height
+///     width: 500
+///     height: 500
+///     visible: true
+///   }
+/// }
+/// ```
+class ProxyPopupWindow: public ProxyWindowBase {
+	QSDOC_BASECLASS(WindowInterface);
+	Q_OBJECT;
+	// clang-format off
+	/// The parent window of this popup.
+	///
+	/// Changing this property reparents the popup.
+	Q_PROPERTY(QObject* parentWindow READ parentWindow WRITE setParentWindow NOTIFY parentWindowChanged);
+	/// The X position of the popup relative to the parent window.
+	Q_PROPERTY(qint32 relativeX READ relativeX WRITE setRelativeX NOTIFY relativeXChanged);
+	/// The Y position of the popup relative to the parent window.
+	Q_PROPERTY(qint32 relativeY READ relativeY WRITE setRelativeY NOTIFY relativeYChanged);
+	/// If the window is shown or hidden. Defaults to false.
+	QSDOC_PROPERTY_OVERRIDE(bool visible READ isVisible WRITE setVisible NOTIFY visibleChanged);
+	/// The screen that the window currently occupies.
+	///
+	/// This may be modified to move the window to the given screen.
+	QSDOC_PROPERTY_OVERRIDE(QuickshellScreenInfo* screen READ screen NOTIFY screenChanged);
+	// clang-format on
+	QML_NAMED_ELEMENT(PopupWindow);
+
+public:
+	explicit ProxyPopupWindow(QObject* parent = nullptr);
+
+	void setupWindow() override;
+
+	void setScreen(QuickshellScreenInfo* screen) override;
+	void setVisible(bool visible) override;
+
+	[[nodiscard]] qint32 x() const override;
+
+	[[nodiscard]] QObject* parentWindow() const;
+	void setParentWindow(QObject* parent);
+
+	[[nodiscard]] qint32 relativeX() const;
+	void setRelativeX(qint32 x);
+
+	[[nodiscard]] qint32 relativeY() const;
+	void setRelativeY(qint32 y);
+
+signals:
+	void parentWindowChanged();
+	void relativeXChanged();
+	void relativeYChanged();
+
+private slots:
+	void onParentConnected();
+	void onParentDestroyed();
+	void updateX();
+	void updateY();
+
+private:
+	QQuickWindow* parentBackingWindow();
+	void updateTransientParent();
+	void updateVisible();
+
+	QObject* mParentWindow = nullptr;
+	ProxyWindowBase* mParentProxyWindow = nullptr;
+	qint32 mRelativeX = 0;
+	qint32 mRelativeY = 0;
+	bool wantsVisible = false;
+};