QmlDesigner: Enable drag-n-drop a material to a model in Navigator

Fixes: QDS-6694
Change-Id: I2fb32052559b1d459cc8025e9f30368b0189e8ab
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@qt.io>
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>

share/qtcreator/qmldesigner/materialBrowserQmlSource/MaterialItem.qml

@@ -72,9 +72,12 @@ Rectangle {
         anchors.fill: parent
         acceptedButtons: Qt.LeftButton | Qt.RightButton
 
-        onClicked: (mouse) => {
+        onPressed: (mouse) => {
             materialBrowserModel.selectMaterial(index)
-            if (mouse.button === Qt.RightButton)
+
+            if (mouse.button === Qt.LeftButton)
+                rootView.startDragMaterial(index, mapToGlobal(mouse.x, mouse.y))
+            else if (mouse.button === Qt.RightButton)
                 root.showContextMenu()
         }
 

src/plugins/qmldesigner/components/materialbrowser/materialbrowserwidget.cpp

@@ -32,6 +32,7 @@
 #include <designermcumanager.h>
 #include <documentmanager.h>
 #include <qmldesignerconstants.h>
+#include <qmldesignerplugin.h>
 
 #include <utils/algorithm.h>
 #include <utils/stylehelper.h>
@@ -103,6 +104,27 @@ bool MaterialBrowserWidget::eventFilter(QObject *obj, QEvent *event)
     if (event->type() == QEvent::FocusOut) {
         if (obj == m_quickWidget.data())
             QMetaObject::invokeMethod(m_quickWidget->rootObject(), "closeContextMenu");
+    } else if (event->type() == QMouseEvent::MouseMove) {
+        DesignDocument *document = QmlDesignerPlugin::instance()->currentDesignDocument();
+        QTC_ASSERT(document, return false);
+        Model *model = document->currentModel();
+        QTC_ASSERT(model, return false);
+
+        if (m_materialToDrag.isValid()) {
+            QMouseEvent *me = static_cast<QMouseEvent *>(event);
+            if ((me->globalPos() - m_dragStartPoint).manhattanLength() > 10) {
+                QByteArray data;
+                QMimeData *mimeData = new QMimeData;
+                QDataStream stream(&data, QIODevice::WriteOnly);
+                stream << m_materialToDrag.internalId();
+                mimeData->setData(Constants::MIME_TYPE_MATERIAL, data);
+                mimeData->removeFormat("text/plain");
+
+                model->startDrag(mimeData, m_previewImageProvider->requestPixmap(
+                                 QString::number(m_materialToDrag.internalId()), nullptr, {128, 128}));
+                m_materialToDrag = {};
+            }
+        }
     }
 
     return QObject::eventFilter(obj, event);
@@ -166,6 +188,12 @@ void MaterialBrowserWidget::handleSearchfilterChanged(const QString &filterText)
     }
 }
 
+void MaterialBrowserWidget::startDragMaterial(int index, const QPointF &mousePos)
+{
+    m_materialToDrag = m_materialBrowserModel->materialAt(index);
+    m_dragStartPoint = mousePos.toPoint();
+}
+
 QString MaterialBrowserWidget::qmlSourcesPath()
 {
 #ifdef SHARE_QML_PATH

src/plugins/qmldesigner/components/materialbrowser/materialbrowserwidget.h

@@ -69,6 +69,7 @@ public:
     void updateMaterialPreview(const ModelNode &node, const QPixmap &pixmap);
 
     Q_INVOKABLE void handleSearchfilterChanged(const QString &filterText);
+    Q_INVOKABLE void startDragMaterial(int index, const QPointF &mousePos);
 
     QQuickWidget *quickWidget() const;
 
@@ -86,6 +87,9 @@ private:
     PreviewImageProvider *m_previewImageProvider = nullptr;
 
     QString m_filterText;
+
+    ModelNode m_materialToDrag;
+    QPoint m_dragStartPoint;
 };
 
 } // namespace QmlDesigner

src/plugins/qmldesigner/components/navigator/choosefrompropertylistdialog.cpp

@@ -56,6 +56,8 @@ ChooseFromPropertyListFilter::ChooseFromPropertyListFilter(const NodeMetaInfo &i
     // ParticleAbstractShape3D
     //  -> ParticleEmitter3D
     //  -> Attractor3D
+    // Material
+    //  -> Model
 
     const TypeName textureType = "QtQuick3D.Texture";
     if (insertInfo.isSubclassOf(textureType)) {
@@ -104,6 +106,9 @@ ChooseFromPropertyListFilter::ChooseFromPropertyListFilter(const NodeMetaInfo &i
         if (parentInfo.isSubclassOf("QtQuick3D.Particles3D.ParticleEmitter3D")
                 || parentInfo.isSubclassOf("QtQuick3D.Particles3D.Attractor3D"))
             propertyList.append("shape");
+    } else if (insertInfo.isSubclassOf("QtQuick3D.Material")) {
+        if (parentInfo.isSubclassOf("QtQuick3D.Particles3D.Model"))
+            propertyList.append("materials");
     }
 }
 

src/plugins/qmldesigner/components/navigator/navigatortreemodel.cpp

@@ -464,6 +464,7 @@ QStringList NavigatorTreeModel::mimeTypes() const
 {
     const static QStringList types({Constants::MIME_TYPE_MODELNODE_LIST,
                                     Constants::MIME_TYPE_ITEM_LIBRARY_INFO,
+                                    Constants::MIME_TYPE_MATERIAL,
                                     Constants::MIME_TYPE_ASSETS});
 
     return types;
@@ -559,6 +560,8 @@ bool NavigatorTreeModel::dropMimeData(const QMimeData *mimeData,
     if (dropModelIndex.model() == this) {
         if (mimeData->hasFormat(Constants::MIME_TYPE_ITEM_LIBRARY_INFO)) {
             handleItemLibraryItemDrop(mimeData, rowNumber, dropModelIndex);
+        } else if (mimeData->hasFormat(Constants::MIME_TYPE_MATERIAL)) {
+            handleMaterialDrop(mimeData, rowNumber, dropModelIndex);
         } else if (mimeData->hasFormat(Constants::MIME_TYPE_ASSETS)) {
             const QStringList assetsPaths = QString::fromUtf8(mimeData->data(Constants::MIME_TYPE_ASSETS)).split(',');
             NodeAbstractProperty targetProperty;
@@ -779,6 +782,33 @@ void NavigatorTreeModel::handleItemLibraryItemDrop(const QMimeData *mimeData, in
     }
 }
 
+void NavigatorTreeModel::handleMaterialDrop(const QMimeData *mimeData, int rowNumber, const QModelIndex &dropModelIndex)
+{
+    QTC_ASSERT(m_view, return);
+
+    const QModelIndex rowModelIndex = dropModelIndex.sibling(dropModelIndex.row(), 0);
+    int targetRowNumber = rowNumber;
+    NodeAbstractProperty targetProperty;
+
+    bool foundTarget = findTargetProperty(rowModelIndex, this, &targetProperty, &targetRowNumber, "materials");
+    if (!foundTarget)
+        return;
+
+    ModelNode targetNode = targetProperty.parentModelNode();
+    if (!targetNode.isSubclassOf("QtQuick3D.Model"))
+        return;
+
+    QByteArray data = mimeData->data(Constants::MIME_TYPE_MATERIAL);
+    QDataStream stream(data);
+    qint32 internalId;
+    stream >> internalId;
+    ModelNode matNode = m_view->modelNodeForInternalId(internalId);
+
+    m_view->executeInTransaction(__FUNCTION__, [&] {
+        m_view->assignMaterialTo3dModel(targetNode, matNode);
+    });
+}
+
 ModelNode NavigatorTreeModel::handleItemLibraryImageDrop(const QString &imagePath,
                                                          NodeAbstractProperty targetProperty,
                                                          const QModelIndex &rowModelIndex,

src/plugins/qmldesigner/components/navigator/navigatortreemodel.h

@@ -115,6 +115,7 @@ private:
                               int targetIndex, bool executeInTransaction = true);
     void handleInternalDrop(const QMimeData *mimeData, int rowNumber, const QModelIndex &dropModelIndex);
     void handleItemLibraryItemDrop(const QMimeData *mimeData, int rowNumber, const QModelIndex &dropModelIndex);
+    void handleMaterialDrop(const QMimeData *mimeData, int rowNumber, const QModelIndex &dropModelIndex);
     ModelNode handleItemLibraryImageDrop(const QString &imagePath, NodeAbstractProperty targetProperty,
                                          const QModelIndex &rowModelIndex, bool &outMoveNodesAfter);
     ModelNode handleItemLibraryFontDrop(const QString &fontFamily, NodeAbstractProperty targetProperty,

src/plugins/qmldesigner/components/navigator/navigatorview.cpp

@@ -276,6 +276,15 @@ void NavigatorView::dragStarted(QMimeData *mimeData)
 
         m_widget->setDragType(itemLibraryEntry.typeName());
         m_widget->update();
+    } else if (mimeData->hasFormat(Constants::MIME_TYPE_MATERIAL)) {
+        QByteArray data = mimeData->data(Constants::MIME_TYPE_MATERIAL);
+        QDataStream stream(data);
+        qint32 internalId;
+        stream >> internalId;
+        ModelNode matNode = modelNodeForInternalId(internalId);
+
+        m_widget->setDragType(matNode.metaInfo().typeName());
+        m_widget->update();
     }
 }
 

src/plugins/qmldesigner/qmldesignerconstants.h

@@ -92,6 +92,7 @@ const char MATERIAL_LIB_ID[] = "__materialLibrary__";
 
 const char MIME_TYPE_ITEM_LIBRARY_INFO[] = "application/vnd.qtdesignstudio.itemlibraryinfo";
 const char MIME_TYPE_ASSETS[]            = "application/vnd.qtdesignstudio.assets";
+const char MIME_TYPE_MATERIAL[]          = "application/vnd.qtdesignstudio.material";
 const char MIME_TYPE_ASSET_IMAGE[]       = "application/vnd.qtdesignstudio.asset.image";
 const char MIME_TYPE_ASSET_FONT[]        = "application/vnd.qtdesignstudio.asset.font";
 const char MIME_TYPE_ASSET_SHADER[]      = "application/vnd.qtdesignstudio.asset.shader";