Fix dragging binding loops and the subpresentation drag dialog issues

Binding loops while dragging were caused by QML drag implementation
that was unneeded since the drag is actually handled by C++ QDrag.
Removed the superfluous QML drag things. This also seemed to fix
the duplicate drag layer/texture/cancel dialog that sometimes happened.

Additially, the layer/texture/cancel dialog was modified to use
explicit layer and texture buttons instead of renamed standard buttons.

Task-number: QT3DS-2397
Change-Id: I86c8ab61e4450b4aff3ef4bb9cae3776aa47959a
Reviewed-by: Mats Honkamaa <mats.honkamaa@qt.io>
Reviewed-by: Kimmo Leppälä <kimmo.leppala@qt.io>
Reviewed-by: Mahmoud Badri <mahmoud.badri@qt.io>
Reviewed-by: Tomi Korpipää <tomi.korpipaa@qt.io>

5 files changed, 51 insertions, 52 deletions

diff --git a/src/Authoring/Studio/DragAndDrop/SceneDropTarget.cpp b/src/Authoring/Studio/DragAndDrop/SceneDropTarget.cpp
index 3bd3b704..1170ed15 100644
--- a/src/Authoring/Studio/DragAndDrop/SceneDropTarget.cpp
+++ b/src/Authoring/Studio/DragAndDrop/SceneDropTarget.cpp
@@ -44,6 +44,7 @@
 #include "Qt3DSDMSlides.h"
 #include "PresentationFile.h"
 #include "QtWidgets/qmessagebox.h"
+#include "QtWidgets/qpushbutton.h"
 
 // Sceneview stuff
 //===============================================================================
@@ -147,15 +148,15 @@ bool CSceneViewDropTarget::Drop(CDropSource &inSource)
         QMessageBox msgBox;
         msgBox.setWindowTitle(QObject::tr("Set Sub-presentation"));
         msgBox.setText(QObject::tr("Set as sub-presentation to"));
-        msgBox.setStandardButtons(QMessageBox::Yes | QMessageBox::No | QMessageBox::Cancel);
-        msgBox.setButtonText(QMessageBox::Yes, QObject::tr("Layer"));
-        msgBox.setButtonText(QMessageBox::No, QObject::tr("Texture"));
+        QPushButton *layerButton = msgBox.addButton(QObject::tr("Layer"), QMessageBox::YesRole);
+        QPushButton *textureButton = msgBox.addButton(QObject::tr("Texture"), QMessageBox::NoRole);
+        msgBox.addButton(QMessageBox::Cancel);
 
-        int choice = msgBox.exec();
-        if (choice == QMessageBox::Yes) { // layer
+        msgBox.exec();
+        if (msgBox.clickedButton() == layerButton) {
             instance = doc->GetActiveLayer();
             // The GenerateAssetCommand below will take care of setting the subpresentation
-        } else if (choice == QMessageBox::No) { // texture
+        } else if (msgBox.clickedButton() == textureButton) { // texture
             instance = doc->GetActiveRootInstance();
             // The GenerateAssetCommand below will take care of setting the subpresentation
         } else {
diff --git a/src/Authoring/Studio/Palettes/BasicObjects/BasicObjectsView.cpp b/src/Authoring/Studio/Palettes/BasicObjects/BasicObjectsView.cpp
index 3b0b3ef7..e3b35963 100644
--- a/src/Authoring/Studio/Palettes/BasicObjects/BasicObjectsView.cpp
+++ b/src/Authoring/Studio/Palettes/BasicObjects/BasicObjectsView.cpp
@@ -57,6 +57,7 @@ QSize BasicObjectsView::sizeHint() const
 
 void BasicObjectsView::startDrag(QQuickItem *item, int row)
 {
+    item->grabMouse(); // Grab to make sure we can ungrab after the drag
     const auto index = m_ObjectsModel->index(row);
 
     QDrag drag(this);
diff --git a/src/Authoring/Studio/Palettes/BasicObjects/BasicObjectsView.qml b/src/Authoring/Studio/Palettes/BasicObjects/BasicObjectsView.qml
index 02080167..5f469a5a 100644
--- a/src/Authoring/Studio/Palettes/BasicObjects/BasicObjectsView.qml
+++ b/src/Authoring/Studio/Palettes/BasicObjects/BasicObjectsView.qml
@@ -53,19 +53,24 @@ Rectangle {
                 id: dragItem
                 anchors.fill: parent
 
-                Drag.active: dragArea.drag.active
-                Drag.hotSpot.x: width / 2
-                Drag.hotSpot.y: height / 2
-                Drag.dragType: Drag.Automatic
-                Drag.supportedActions: Qt.CopyAction
-
                 MouseArea {
                     id: dragArea
+                    property bool dragStarted: false
+                    property point pressPoint
+
                     anchors.fill: parent
-                    drag.target: dragItem
+                    onPressed: {
+                        pressPoint = Qt.point(mouse.x, mouse.y);
+                        dragStarted = false;
+                    }
+                    onPositionChanged: {
+                        if (!dragStarted && (Math.abs(mouse.x - pressPoint.x) > 4
+                                             || Math.abs(mouse.y - pressPoint.y) > 4)) {
+                            dragStarted = true;
+                            _basicObjectsView.startDrag(dragItem, index);
+                        }
+                    }
                 }
-
-                Drag.onDragStarted: _basicObjectsView.startDrag(dragArea, model.index)
             }
             Row {
                 id: contentRow
diff --git a/src/Authoring/Studio/Palettes/Project/ProjectView.cpp b/src/Authoring/Studio/Palettes/Project/ProjectView.cpp
index 05c68ecd..6b7a5a49 100644
--- a/src/Authoring/Studio/Palettes/Project/ProjectView.cpp
+++ b/src/Authoring/Studio/Palettes/Project/ProjectView.cpp
@@ -271,6 +271,7 @@ void ProjectView::mousePressEvent(QMouseEvent *event)
 
 void ProjectView::startDrag(QQuickItem *item, int row)
 {
+    item->grabMouse(); // Grab to make sure we can ungrab after the drag
     const auto index = m_ProjectModel->index(row);
 
     QDrag drag(this);
@@ -281,6 +282,8 @@ void ProjectView::startDrag(QQuickItem *item, int row)
         drag.exec(Qt::IgnoreAction);
     else
         drag.exec(Qt::CopyAction);
+
+    // Ungrab to trigger mouse release on the originating item
     QTimer::singleShot(0, item, &QQuickItem::ungrabMouse);
 }
 
diff --git a/src/Authoring/Studio/Palettes/Project/ProjectView.qml b/src/Authoring/Studio/Palettes/Project/ProjectView.qml
index f7d9c56f..0144144b 100644
--- a/src/Authoring/Studio/Palettes/Project/ProjectView.qml
+++ b/src/Authoring/Studio/Palettes/Project/ProjectView.qml
@@ -71,10 +71,26 @@ Rectangle {
                 delegate: Rectangle {
                     id: delegateItem
                     property bool dragging: false
+                    property bool dragStarted: false
+                    property point pressPoint
                     width: parent.width
                     height: 20
                     color: (index == projectTree.currentIndex || dragging) ? _selectionColor
                                                                            : "transparent"
+                    function handlePress(mouse) {
+                        if (_isDraggable) {
+                            pressPoint = Qt.point(mouse.x, mouse.y);
+                            dragStarted = false;
+                        }
+                    }
+                    function handlePositionChange(mouse, item) {
+                        if (_isDraggable && !dragStarted
+                                && (Math.abs(mouse.x - pressPoint.x) > 4
+                                    || Math.abs(mouse.y - pressPoint.y) > 4)) {
+                            dragStarted = true;
+                            _parentView.startDrag(item, index);
+                        }
+                    }
 
                     Row {
                         x: _depth*28
@@ -98,54 +114,27 @@ Rectangle {
                         }
 
                         Image {
+                            id: fileIconImage
                             source: fileIcon
-
-                            Item {
-                                id: dragItemIcon
-
-                                visible: _isDraggable
+                            MouseArea {
                                 anchors.fill: parent
-
-                                Drag.active: dragAreaIcon.drag.active
-                                Drag.hotSpot.x: width / 2
-                                Drag.hotSpot.y: height / 2
-                                Drag.dragType: Drag.Automatic
-                                Drag.supportedActions: Qt.CopyAction
-
-                                MouseArea {
-                                    id: dragAreaIcon
-                                    anchors.fill: parent
-                                    drag.target: dragItemIcon
-                                }
-
-                                Drag.onDragStarted: _parentView.startDrag(dragAreaIcon, index)
+                                onPressed: delegateItem.handlePress(mouse)
+                                onPositionChanged: delegateItem.handlePositionChange(mouse,
+                                                                                     fileIconImage)
                             }
                         }
 
                         StyledLabel {
+                            id: fileNameLabel
                             text: fileName
                             color: _isReferenced ? _textColor : _disabledColor
                             leftPadding: 2
 
-                            Item {
-                                id: dragItem
-
-                                visible: _isDraggable
+                            MouseArea {
                                 anchors.fill: parent
-
-                                Drag.active: dragArea.drag.active
-                                Drag.hotSpot.x: width / 2
-                                Drag.hotSpot.y: height / 2
-                                Drag.dragType: Drag.Automatic
-                                Drag.supportedActions: Qt.CopyAction
-
-                                MouseArea {
-                                    id: dragArea
-                                    anchors.fill: parent
-                                    drag.target: dragItem
-                                }
-
-                                Drag.onDragStarted: _parentView.startDrag(dragArea, index)
+                                onPressed: delegateItem.handlePress(mouse)
+                                onPositionChanged: delegateItem.handlePositionChange(mouse,
+                                                                                     fileNameLabel)
                             }
                         }
                     }