try a different approach to dragging

containments/homescreen2/CMakeLists.txt

@@ -11,6 +11,7 @@ target_link_libraries(plasma_containment_phone_homescreen2
                       Qt5::Gui
                       KF5::Plasma
                       Qt5::Qml
+                      Qt5::Quick
                       KF5::I18n
                       KF5::Service
                       KF5::KIOWidgets

containments/homescreen2/homescreen.cpp

@@ -22,6 +22,7 @@
 
 #include <QtQml>
 #include <QDebug>
+#include <QQuickItem>
 
 HomeScreen::HomeScreen(QObject *parent, const QVariantList &args)
     : Plasma::Containment(parent, args)
@@ -39,6 +40,16 @@ ApplicationListModel *HomeScreen::applicationListModel()
     return m_applicationListModel;
 }
 
+void HomeScreen::orderItems(QQuickItem *item1, QQuickItem *item2)
+{
+    if (!item1 || !item2 || item1->parentItem() != item2->parentItem()) {
+        return;
+    }
+
+    item1->stackBefore(item2);
+}
+
+
 K_EXPORT_PLASMA_APPLET_WITH_JSON(homescreen, HomeScreen, "metadata.json")
 
 #include "homescreen.moc"

containments/homescreen2/homescreen.h

@@ -24,6 +24,7 @@
 
 #include <Plasma/Containment>
 
+class QQuickItem;
 class ApplicationListModel;
 
 class HomeScreen : public Plasma::Containment
@@ -37,6 +38,8 @@ public:
 
     ApplicationListModel *applicationListModel();
 
+    Q_INVOKABLE void orderItems(QQuickItem *item1, QQuickItem *item2);
+
 private:
     ApplicationListModel *m_applicationListModel;
 

containments/homescreen2/package/contents/ui/launcher/Delegate.qml

@@ -33,8 +33,9 @@ ContainmentLayoutManager.ItemContainer {
     z: dragging ? 1 : 0
 
     property var modelData: typeof model !== "undefined" ? model : null
-    property bool dragging
+    property ContainmentLayoutManager.ItemContainer beforeItem
-    property ContainmentLayoutManager.ItemContainer dragDelegate
+    property Item container
+    property ContainmentLayoutManager.ItemContainer before
 
     leftPadding: units.smallSpacing * 2
     topPadding: units.smallSpacing * 2
@@ -46,29 +47,29 @@ ContainmentLayoutManager.ItemContainer {
     editModeCondition: ContainmentLayoutManager.ItemContainer.AfterPressAndHold//model.ApplicationOnDesktopRole ? ContainmentLayoutManager.ItemContainer.AfterPressAndHold: ContainmentLayoutManager.ItemContainer.Manual
     onEditModeChanged: {//FIXME: remove
         plasmoid.editMode = editMode
+        if (!editMode) {
+            root.forceLayout();
+        }
     }
     onDragActiveChanged: {
         if (dragActive) {
+            if (container) {
+                container.showSpacerBefore(delegate);
+            }
             return;
         }
         
         plasmoid.editMode = false;
         editMode = false;
-        launcher.forceLayout();
+        if (container) {
-        favoriteStrip.forceLayout();
+            container.forceLayout();
+            container.hideSpacer();
+        }
     }
 
-    onDraggingChanged: {
+    onParentChanged: {
-        if (dragging) {
+        if (container) {
-            var pos = dragDelegate.parent.mapFromItem(delegate, 0, 0);
+            plasmoid.nativeInterface.orderItems(delegate, before);
-            dragDelegate.parent = delegate.parent.parent;
-            dragDelegate.x = delegate.x
-            dragDelegate.y = delegate.y
-            dragDelegate.modelData = model;
-            root.reorderingApps = true;
-        } else {
-            dragDelegate.modelData = null;
-            root.reorderingApps = false;
         }
     }
 
@@ -80,6 +81,7 @@ ContainmentLayoutManager.ItemContainer {
         if (favoriteStrip.contains(favoriteStrip.mapFromItem(delegate, dragCenter.x, dragCenter.y))) {
             var pos = favoriteStrip.mapFromItem(delegate, 0, 0);
             newRow = Math.floor((pos.x + dragCenter.x) / delegate.width);
+            before = favoriteStrip.flow.childAt(delegate.x + dragCenter.x, delegate.y + dragCenter.y);
 
         // Put it on desktop
         } else if (appletsLayout.contains(appletsLayout.mapFromItem(delegate, dragCenter.x, dragCenter.y))) {
@@ -87,17 +89,23 @@ ContainmentLayoutManager.ItemContainer {
             plasmoid.nativeInterface.applicationListModel.setDesktopItem(index, true);
             delegate.x = pos.x
             delegate.y = pos.y
+            before = null;
             return;
     
         // Put it in the general view
         } else {
             newRow = Math.round(applicationsFlow.width / delegate.width) * Math.floor((delegate.y + dragCenter.y) / delegate.height) + Math.floor((delegate.x + dragCenter.x) / delegate.width) + favoriteStrip.count;
+            before = applicationsFlow.childAt(delegate.x + dragCenter.x, delegate.y + dragCenter.y);
         }
 
         plasmoid.nativeInterface.applicationListModel.setDesktopItem(index, false);
 
         plasmoid.nativeInterface.applicationListModel.moveItem(modelData.index, newRow);
 
+        if (container) {
+            container.showSpacerBefore(before);
+        }
+
         //delegate.x = newPosition.x;
     }
 

containments/homescreen2/package/contents/ui/launcher/FavoriteStrip.qml

@@ -29,12 +29,23 @@ import org.kde.kquickcontrolsaddons 2.0
 Controls.Control {
     id: root
 
+    property alias flow: applicationsFlow
+
+    property Controls.Control launcherGrid
+    readonly property int count: applicationsFlow.width / launcherGrid.cellWidth
+
     function forceLayout() {
         applicationsFlow.forceLayout();
     }
 
-    property Controls.Control launcherGrid
+    function showSpacerBefore(item) {
-    readonly property int count: applicationsFlow.width / launcherGrid.cellWidth
+        spacer.parent = applicationsFlow
+        plasmoid.nativeInterface.orderItems(spacer, item);
+    }
+
+    function hideSpacer() {
+        spacer.parent = flowParent;
+    }
 
     implicitHeight: applicationsFlow.implicitHeight + frame.margins.top + frame.margins.bottom
 
@@ -49,16 +60,30 @@ Controls.Control {
         anchors.fill: parent
     }
 
-    contentItem: Flow {
+    contentItem: Item {
-        id: applicationsFlow
+        id: flowParent
 
-        spacing: 0
+        implicitWidth: applicationsFlow.implicitWidth
+        implicitHeight: applicationsFlow.implicitHeight
 
-        move: Transition {
+        Item {
-            NumberAnimation {
+            id: spacer
-                duration: units.longDuration
+            width: units.gridUnit * 4
-                easing.type: Easing.InOutQuad
+            height: width
-                properties: "x,y"
+        }
+
+        Flow {
+            id: applicationsFlow
+            anchors.fill: parent
+
+            spacing: 0
+
+            move: Transition {
+                NumberAnimation {
+                    duration: units.longDuration
+                    easing.type: Easing.InOutQuad
+                    properties: "x,y"
+                }
             }
         }
     }

containments/homescreen2/package/contents/ui/launcher/LauncherGrid.qml

@@ -30,9 +30,8 @@ import org.kde.plasma.private.containmentlayoutmanager 1.0 as ContainmentLayoutM
 Controls.Control {
     id: root
 
-    function forceLayout() {
+    property alias flow: applicationsFlow
-        applicationsFlow.forceLayout();
+
-    }
     readonly property bool dragging: applicationsFlow.dragData
     property bool reorderingApps: false
 
@@ -49,6 +48,19 @@ Controls.Control {
     signal externalDragStarted
     signal dragPositionChanged(point pos)
 
+    function forceLayout() {
+        applicationsFlow.forceLayout();
+    }
+
+    function showSpacerBefore(item) {
+        spacer.parent = applicationsFlow
+        plasmoid.nativeInterface.orderItems(spacer, item);
+    }
+
+    function hideSpacer() {
+        spacer.parent = flowParent;
+    }
+
     implicitHeight: applicationsFlow.implicitHeight + frame.margins.top + frame.margins.bottom
 
     leftPadding: frame.margins.left
@@ -63,6 +75,7 @@ Controls.Control {
     }
 
     contentItem: Item {
+        id: flowParent
         //NOTE: TextMetrics can't handle multi line
         Controls.Label {
             id: metrics
@@ -70,19 +83,12 @@ Controls.Control {
             visible: false
         }
 
-        //This Delegate is the placeholder for the "drag"
+        Item {
-        //delegate (that is not actual drag and drop
+            id: spacer
-        Delegate {
+            width: units.gridUnit * 4
-            id: dragDelegateItem
+            height: width
-            z: 999
+            visible:parent == applicationsFlow
-            width: root.cellWidth
-            height: root.cellHeight
-            onYChanged: dragPositionChanged(Qt.point(x, y))
-            opacity: 1
-
-            visible: modelData !== null
         }
-
         Flow {
             id: applicationsFlow
             anchors.fill: parent
@@ -114,15 +120,31 @@ Controls.Control {
                 delegate: Delegate {
                     width: root.cellWidth
                     height: root.cellHeight
-                    dragDelegate: dragDelegateItem
+                    container: {
+                        if (model.ApplicationOnDesktopRole) {
+                            return null;
+                        }
+                        if (index < favoriteStrip.count) {
+                            return favoriteStrip;
+                        }
+                        return root;
+                    }
                     parent: {
                         if (model.ApplicationOnDesktopRole) {
                             return appletsLayout;
                         }
                         if (index < favoriteStrip.count) {
-                            return favoriteStrip.contentItem;
+                            if (editMode) {
+                                return favoriteStrip.contentItem;
+                            } else {
+                                return favoriteStrip.flow;
+                            }
+                        }
+                        if (editMode) {
+                            return flowParent;
+                        } else {
+                            return applicationsFlow;
                         }
-                        return applicationsFlow;
                     }
                 }
             }