QQmlDelegateModelItem: set row and column explicit

Whenever we set a model index on a model item, set row and
column explicit as well. We used to calculate row and column
by calling out to QQmlDelegateModel from within
QQmlDelegateModelItem. But we want to remove the dependency
to QQmlDelegateModel as much as possible, to be able to reuse
QQmlDelegateModelItem also from other model classes (first and
foremost the upcoming QQmlTableInstanceModel).

Change-Id: Ib80b31250010b2611ba1715d3324145117add865
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

2 files changed, 34 insertions, 21 deletions

diff --git a/src/qml/types/qqmldelegatemodel.cpp b/src/qml/types/qqmldelegatemodel.cpp
index 0dbd9731c9..d62cc5d334 100644
--- a/src/qml/types/qqmldelegatemodel.cpp
+++ b/src/qml/types/qqmldelegatemodel.cpp
@@ -1312,8 +1312,12 @@ void QQmlDelegateModel::_q_itemsInserted(int index, int count)
     const QList<QQmlDelegateModelItem *> cache = d->m_cache;
     for (int i = 0, c = cache.count();  i < c; ++i) {
         QQmlDelegateModelItem *item = cache.at(i);
-        if (item->modelIndex() >= index)
-            item->setModelIndex(item->modelIndex() + count);
+        if (item->modelIndex() >= index) {
+            const int newIndex = item->modelIndex() + count;
+            const int row = newIndex;
+            const int column = 0;
+            item->setModelIndex(newIndex, row, column);
+        }
     }
 
     QVector<Compositor::Insert> inserts;
@@ -1454,10 +1458,14 @@ void QQmlDelegateModel::_q_itemsRemoved(int index, int count)
         if (!d->m_cache.contains(item))
             continue;
 
-        if (item->modelIndex() >= index + count)
-            item->setModelIndex(item->modelIndex() - count);
-        else  if (item->modelIndex() >= index)
-            item->setModelIndex(-1);
+        if (item->modelIndex() >= index + count) {
+            const int newIndex = item->modelIndex() - count;
+            const int row = newIndex;
+            const int column = 0;
+            item->setModelIndex(newIndex, row, column);
+        } else if (item->modelIndex() >= index) {
+            item->setModelIndex(-1, -1, -1);
+        }
     }
 
     QVector<Compositor::Remove> removes;
@@ -1502,10 +1510,17 @@ void QQmlDelegateModel::_q_itemsMoved(int from, int to, int count)
     const QList<QQmlDelegateModelItem *> cache = d->m_cache;
     for (int i = 0, c = cache.count();  i < c; ++i) {
         QQmlDelegateModelItem *item = cache.at(i);
-        if (item->modelIndex() >= from && item->modelIndex() < from + count)
-            item->setModelIndex(item->modelIndex() - from + to);
-        else if (item->modelIndex() >= minimum && item->modelIndex() < maximum)
-            item->setModelIndex(item->modelIndex() + difference);
+        if (item->modelIndex() >= from && item->modelIndex() < from + count) {
+            const int newIndex = item->modelIndex() - from + to;
+            const int row = newIndex;
+            const int column = 0;
+            item->setModelIndex(newIndex, row, column);
+        } else if (item->modelIndex() >= minimum && item->modelIndex() < maximum) {
+            const int newIndex = item->modelIndex() + difference;
+            const int row = newIndex;
+            const int column = 0;
+            item->setModelIndex(newIndex, row, column);
+        }
     }
 
     QVector<Compositor::Remove> removes;
@@ -1562,7 +1577,7 @@ void QQmlDelegateModel::_q_modelReset()
         for (int i = 0, c = cache.count();  i < c; ++i) {
             QQmlDelegateModelItem *item = cache.at(i);
             if (item->modelIndex() != -1)
-                item->setModelIndex(-1);
+                item->setModelIndex(-1, -1, -1);
         }
 
         QVector<Compositor::Remove> removes;
@@ -1959,8 +1974,7 @@ void QV4::Heap::QQmlDelegateModelItemObject::destroy()
 }
 
 
-QQmlDelegateModelItem::QQmlDelegateModelItem(
-        QQmlDelegateModelItemMetaType *metaType, int modelIndex)
+QQmlDelegateModelItem::QQmlDelegateModelItem(QQmlDelegateModelItemMetaType *metaType, int modelIndex, int row, int column)
     : v4(metaType->v4Engine)
     , metaType(metaType)
     , contextData(nullptr)
@@ -1971,8 +1985,8 @@ QQmlDelegateModelItem::QQmlDelegateModelItem(
     , scriptRef(0)
     , groups(0)
     , index(modelIndex)
-    , row(QQmlDelegateModelPrivate::get(metaType->model)->m_adaptorModel.rowAt(modelIndex))
-    , column(QQmlDelegateModelPrivate::get(metaType->model)->m_adaptorModel.columnAt(modelIndex))
+    , row(row)
+    , column(column)
 {
     metaType->addref();
 }
@@ -2007,18 +2021,17 @@ void QQmlDelegateModelItem::Dispose()
     delete this;
 }
 
-void QQmlDelegateModelItem::setModelIndex(int idx)
+void QQmlDelegateModelItem::setModelIndex(int idx, int newRow, int newColumn)
 {
     if (idx == index)
         return;
 
     const int prevRow = row;
     const int prevColumn = column;
-    const QQmlAdaptorModel &adaptorModel = QQmlDelegateModelPrivate::get(metaType->model)->m_adaptorModel;
 
     index = idx;
-    row = adaptorModel.rowAt(idx);
-    column = adaptorModel.columnAt(idx);
+    row = newRow;
+    column = newColumn;
 
     Q_EMIT modelIndexChanged();
 
diff --git a/src/qml/types/qqmldelegatemodel_p_p.h b/src/qml/types/qqmldelegatemodel_p_p.h
index a0c1f6aa12..0c24e79c1b 100644
--- a/src/qml/types/qqmldelegatemodel_p_p.h
+++ b/src/qml/types/qqmldelegatemodel_p_p.h
@@ -99,7 +99,7 @@ class QQmlDelegateModelItem : public QObject
     Q_PROPERTY(int column MEMBER column NOTIFY columnChanged)
     Q_PROPERTY(QObject *model READ modelObject CONSTANT)
 public:
-    QQmlDelegateModelItem(QQmlDelegateModelItemMetaType *metaType, int modelIndex);
+    QQmlDelegateModelItem(QQmlDelegateModelItemMetaType *metaType, int modelIndex, int row, int column);
     ~QQmlDelegateModelItem();
 
     void referenceObject() { ++objectRef; }
@@ -123,7 +123,7 @@ public:
     int groupIndex(Compositor::Group group);
 
     int modelIndex() const { return index; }
-    virtual void setModelIndex(int idx);
+    virtual void setModelIndex(int idx, int newRow, int newColumn);
 
     virtual QV4::ReturnedValue get() { return QV4::QObjectWrapper::wrap(v4, this); }