1 files changed, 147 insertions, 0 deletions
diff --git a/src/quicklayouts/qquicklayoutitemproxy_p.h b/src/quicklayouts/qquicklayoutitemproxy_p.h
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+++ b/src/quicklayouts/qquicklayoutitemproxy_p.h
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+// Copyright (C) 2023 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
+
+#ifndef QQUICKLAYOUTITEMPROXY_P_H
+#define QQUICKLAYOUTITEMPROXY_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <private/qquickitem_p.h>
+#include <private/qquickrectangle_p.h>
+
+class QQuickLayoutItemProxyAttachedData;
+class QQuickLayoutItemProxyPrivate;
+class QQuickLayoutItemProxy : public QQuickItem
+{
+    Q_OBJECT
+
+    Q_PROPERTY(QQuickItem *target READ target WRITE setTarget NOTIFY targetChanged)
+    QML_NAMED_ELEMENT(LayoutItemProxy)
+    QML_ADDED_IN_VERSION(6, 6)
+
+public:
+    QQuickLayoutItemProxy(QQuickItem *parent = nullptr);
+    ~QQuickLayoutItemProxy() override;
+
+    void geometryChange(const QRectF &newGeom, const QRectF &oldGeom) override;
+    void itemChange(ItemChange c, const ItemChangeData &d) override;
+
+    QQuickItem *target() const;
+    void setTarget(QQuickItem *newTarget);
+    Q_INVOKABLE QQuickItem *effectiveTarget() const;
+    void clearTarget();
+
+    void maybeTakeControl();
+public slots:
+    void updatePos();
+
+private slots:
+    // We define some slots to react to changes to the Layout attached properties.
+    // They are all named following the same scheme, which allows us to use a macro.
+#define propertyForwarding(Property) \
+    void target##Property##Changed(); \
+    void proxy##Property##Changed();
+
+    propertyForwarding(MinimumWidth)
+    propertyForwarding(MinimumHeight)
+    propertyForwarding(PreferredWidth)
+    propertyForwarding(PreferredHeight)
+    propertyForwarding(MaximumWidth)
+    propertyForwarding(MaximumHeight)
+    propertyForwarding(FillWidth)
+    propertyForwarding(FillHeight)
+    propertyForwarding(Alignment)
+    propertyForwarding(HorizontalStretchFactor)
+    propertyForwarding(VerticalStretchFactor)
+    propertyForwarding(Margins)
+    propertyForwarding(LeftMargin)
+    propertyForwarding(TopMargin)
+    propertyForwarding(RightMargin)
+    propertyForwarding(BottomMargin)
+#undef propertyForwarding
+
+signals:
+    void targetChanged();
+
+private:
+    Q_DECLARE_PRIVATE(QQuickLayoutItemProxy)
+};
+
+class QQuickLayoutItemProxyPrivate : public QQuickItemPrivate
+{
+    Q_DECLARE_PUBLIC(QQuickLayoutItemProxy)
+
+public:
+    QQuickLayoutItemProxyPrivate();
+
+    // the target of the LayoutItem
+    QQuickItem *target = nullptr;
+
+    // These values are required to know why the Layout property of the proxy changed
+    // If it changed because the target changed we should keep the connection valid
+    // If a Layout property change is not invoked by the target, it was set
+    // explicitly by the application developer and we should disconnect the connection
+    // between target and proxy for this property.
+    unsigned m_expectProxyMinimumWidthChange : 1;
+    unsigned m_expectProxyMinimumHeightChange : 1;
+    unsigned m_expectProxyPreferredWidthChange : 1;
+    unsigned m_expectProxyPreferredHeightChange : 1;
+    unsigned m_expectProxyMaximumWidthChange : 1;
+    unsigned m_expectProxyMaximumHeightChange : 1;
+    unsigned m_expectProxyFillWidthChange : 1;
+    unsigned m_expectProxyFillHeightChange : 1;
+    unsigned m_expectProxyAlignmentChange : 1;
+    unsigned m_expectProxyHorizontalStretchFactorChange : 1;
+    unsigned m_expectProxyVerticalStretchFactorChange : 1;
+    unsigned m_expectProxyMarginsChange : 1;
+    unsigned m_expectProxyLeftMarginChange : 1;
+    unsigned m_expectProxyTopMarginChange : 1;
+    unsigned m_expectProxyRightMarginChange : 1;
+    unsigned m_expectProxyBottomMarginChange : 1;
+
+    friend class QQuickLayoutItemProxy;
+};
+
+class QQuickLayoutItemProxyAttachedData : public QObject
+{
+    Q_OBJECT
+
+    QML_ANONYMOUS
+    Q_PROPERTY(bool proxyHasControl READ proxyHasControl NOTIFY controllingProxyChanged)
+    Q_PROPERTY(QQuickLayoutItemProxy* controllingProxy READ getControllingProxy NOTIFY controllingProxyChanged)
+    Q_PROPERTY(QQmlListProperty<QQuickLayoutItemProxy> proxies READ getProxies NOTIFY proxiesChanged)
+
+public:
+    QQuickLayoutItemProxyAttachedData(QObject *parent);
+    ~QQuickLayoutItemProxyAttachedData() override;
+    void registerProxy(QQuickLayoutItemProxy *proxy);
+    void releaseProxy(QQuickLayoutItemProxy *proxy);
+    bool takeControl(QQuickLayoutItemProxy *proxy);
+    void releaseControl(QQuickLayoutItemProxy *proxy);
+    QQuickLayoutItemProxy *getControllingProxy() const;
+    QQmlListProperty<QQuickLayoutItemProxy> getProxies();
+    bool proxyHasControl() const;
+
+signals:
+    void controlTaken();
+    void controlReleased();
+    void controllingProxyChanged();
+    void proxiesChanged();
+
+private:
+    QList<QQuickLayoutItemProxy*> proxies;
+    QQuickLayoutItemProxy* controllingProxy;
+};
+
+Q_DECLARE_METATYPE(QQuickLayoutItemProxyAttachedData*);
+
+#endif // QQUICKLAYOUTITEMPROXY_P_H