From c2dc230e73dbab5fc987ef9512c74d2da28f7196 Mon Sep 17 00:00:00 2001
From: jorenchik <jorens.stekels@gmail.com>
Date: Thu, 3 Oct 2024 22:56:37 +0300
Subject: [PATCH] Drag and drop groups

---
 src/cpp/qtapp/trainWindow.cpp | 96 +++++++++++++++++------------------
 1 file changed, 48 insertions(+), 48 deletions(-)

diff --git a/src/cpp/qtapp/trainWindow.cpp b/src/cpp/qtapp/trainWindow.cpp
index 78b8eaa..03b104c 100644
--- a/src/cpp/qtapp/trainWindow.cpp
+++ b/src/cpp/qtapp/trainWindow.cpp
@@ -19,6 +19,7 @@
 #include <QStandardItemModel>
 #include <QDropEvent>
 #include <iostream>
+#include <QDrag>
 
 #include "trainWindow.h"
 #include "parser.h"
@@ -56,6 +57,26 @@ QStandardItemModel *orderModel;
 
 QWidget *wGroupQuestion;
 
+auto listStyle = 
+	"QListView {"
+	"   background-color: white;"
+	"   border: 0px solid black;"
+	"}"
+	"QListView::item::first {"
+	"   padding: 5px 0 0 0;"
+	"}"
+	"QListView::item {"
+	"   color: black;"
+	"   padding: 5px;"
+	"   border: 1px solid gray;"
+	"   background-color: white;"
+	"}"
+	"QListView::item:selected {"
+	"}"
+	"QListView::item:hover {"
+	"   background-color: lightyellow;"
+	"}";
+
 class OrderListView : public QListView
 {
     Q_OBJECT
@@ -89,26 +110,33 @@ class MoveListView : public QListView
     Q_OBJECT
 
 public:
-    explicit MoveListView(QWidget *parent = nullptr) : QListView(parent) {}
+    explicit MoveListView(QWidget *parent = nullptr) : QListView(parent) {
+		setStyleSheet(listStyle);
+		setAcceptDrops(true);
+		setDragDropMode(QAbstractItemView::DragDrop);
+		setDefaultDropAction(Qt::MoveAction);
+	}
 
 protected:
-    void dropEvent(QDropEvent *event) override
-    {
-        QModelIndex sourceIndex = currentIndex();
-        QModelIndex targetIndex = indexAt(event->pos());
+    void dragEnterEvent(QDragEnterEvent *event) override {
+        event->acceptProposedAction();
+    }
 
-        if (sourceIndex.isValid() && targetIndex.isValid()) {
-            QStandardItemModel *model = qobject_cast<QStandardItemModel *>(this->model());
-            if (model) {
-                QVariant sourceData = model->data(sourceIndex);
-                QVariant targetData = model->data(targetIndex);
-                model->setData(sourceIndex, targetData);
-                model->setData(targetIndex, sourceData);
-                event->ignore();
-            }
-        } else {
-			event->ignore();
+    void dragMoveEvent(QDragMoveEvent *event) override {
+        event->acceptProposedAction();
+    }
+
+    void dropEvent(QDropEvent *event) override {
+		QListView *source = qobject_cast<QListView *>(event->source());
+        QStandardItemModel *sourceModel = qobject_cast<QStandardItemModel *>(source->model());
+        QStandardItemModel *targetModel = qobject_cast<QStandardItemModel *>(this->model());
+
+        if (source != this) {
+            QList<QStandardItem *> items = sourceModel->takeRow(source->currentIndex().row());
+            targetModel->appendRow(items);
         }
+
+        event->ignore();
     }
 };
 
@@ -160,26 +188,6 @@ void initTrainWindow() {
 		lQuestionText->hide();
 	}
 
-	auto listStyle = 
-			"QListView {"
-			"   background-color: white;"
-			"   border: 0px solid black;"
-			"}"
-			"QListView::item::first {"
-			"   padding: 5px 0 0 0;"
-			"}"
-			"QListView::item {"
-			"   color: black;"
-			"   padding: 5px;"
-			"   border: 1px solid gray;"
-			"   background-color: white;"
-			"}"
-			"QListView::item:selected {"
-			"}"
-			"QListView::item:hover {"
-			"   background-color: lightyellow;"
-			"}";
-
 	{ // Make multi-choice list.
 		multiChoiceModel = new QStandardItemModel();
 		listView = new QListView();
@@ -278,12 +286,8 @@ void initTrainWindow() {
 		auto vItems     = new QVBoxLayout();
 		itemScroll->setLayout(vItems);
 		itemModel    = new QStandardItemModel();
-		itemListView = new QListView();
+		itemListView = new MoveListView();
 		itemListView->setModel(itemModel);
-		itemListView->setStyleSheet(listStyle);
-		itemListView->setDragEnabled(true);
-		itemListView->setDragDropMode(QAbstractItemView::DragDrop);
-		itemListView->setDefaultDropAction(Qt::MoveAction);
 		vItems->addWidget(itemListView);
 		hGroupQuestion->addWidget(itemScroll);
 
@@ -303,15 +307,11 @@ void initTrainWindow() {
 			auto groupLabel = new QLabel("Group I");
 			auto scrollArea = new QScrollArea();
 			auto groupModel = new QStandardItemModel();
-			auto groupList = new QListView();
-			groupList->setModel(groupModel);
-			groupList->setMaximumHeight(100);
+			auto groupList = new MoveListView();
 			vGroups->addWidget(groupLabel);
 			vGroups->addWidget(groupList);
-			groupList->setStyleSheet(listStyle);
-			groupList->setAcceptDrops(true);
-			groupList->setDragDropMode(QAbstractItemView::DragDrop);
-			groupList->setDefaultDropAction(Qt::MoveAction);
+			groupList->setModel(groupModel);
+			groupList->setMaximumHeight(100);
 		}
 		vGroups->addItem(groupSpacer);