QAbstractProxyModel: Forward drop-related API.

Forward canDropMimeData() and dropMimeData() to the source model.

[ChangeLog][QtCore][QAbstractProxyModel] QAbstractProxyModel now
forwards the drop-related API.

Task-number: QTBUG-39549
Change-Id: Ib81fcec862586e4ecfb99b9e0f4eb1a16eace762
Reviewed-by: Jørgen Lind <jorgen.lind@digia.com>
Reviewed-by: Stephen Kelly <stephen.kelly@kdab.com>

src/corelib/itemmodels/qabstractproxymodel.cpp

@@ -392,6 +392,30 @@ QMimeData* QAbstractProxyModel::mimeData(const QModelIndexList &indexes) const
     return d->model->mimeData(list);
 }
 
+/*!
+    \reimp
+    \since 5.4
+ */
+bool QAbstractProxyModel::canDropMimeData(const QMimeData *data, Qt::DropAction action,
+                                          int row, int column, const QModelIndex &parent) const
+{
+    Q_D(const QAbstractProxyModel);
+    const QModelIndex source = mapToSource(index(row, column, parent));
+    return d->model->canDropMimeData(data, action, source.row(), source.column(), source.parent());
+}
+
+/*!
+    \reimp
+    \since 5.4
+ */
+bool QAbstractProxyModel::dropMimeData(const QMimeData *data, Qt::DropAction action,
+                                       int row, int column, const QModelIndex &parent)
+{
+    Q_D(QAbstractProxyModel);
+    const QModelIndex source = mapToSource(index(row, column, parent));
+    return d->model->dropMimeData(data, action, source.row(), source.column(), source.parent());
+}
+
 /*!
     \reimp
  */

src/corelib/itemmodels/qabstractproxymodel.h

@@ -91,6 +91,10 @@ public:
     QModelIndex sibling(int row, int column, const QModelIndex &idx) const;
 
     QMimeData* mimeData(const QModelIndexList &indexes) const;
+    bool canDropMimeData(const QMimeData *data, Qt::DropAction action,
+                         int row, int column, const QModelIndex &parent) const Q_DECL_OVERRIDE;
+    bool dropMimeData(const QMimeData *data, Qt::DropAction action,
+                      int row, int column, const QModelIndex &parent) Q_DECL_OVERRIDE;
     QStringList mimeTypes() const;
     Qt::DropActions supportedDropActions() const;
 

tests/auto/corelib/itemmodels/qsortfilterproxymodel/tst_qsortfilterproxymodel.cpp

@@ -150,6 +150,8 @@ private slots:
     void chainedProxyModelRoleNames();
 
     void noMapAfterSourceDelete();
+    void forwardDropApi();
+
 protected:
     void buildHierarchy(const QStringList &data, QAbstractItemModel *model);
     void checkHierarchy(const QStringList &data, const QAbstractItemModel *model);
@@ -3875,5 +3877,35 @@ void tst_QSortFilterProxyModel::noMapAfterSourceDelete()
     QVERIFY(!persistent.isValid());
 }
 
+// QTBUG-39549, test whether canDropMimeData(), dropMimeData() are proxied as well
+// by invoking them on a QSortFilterProxyModel proxying a QStandardItemModel that allows drops
+// on row #1, filtering for that row.
+class DropTestModel : public QStandardItemModel {
+public:
+    explicit DropTestModel(QObject *parent = 0) : QStandardItemModel(0, 1, parent)
+    {
+        appendRow(new QStandardItem(QStringLiteral("Row0")));
+        appendRow(new QStandardItem(QStringLiteral("Row1")));
+    }
+
+    bool canDropMimeData(const QMimeData *, Qt::DropAction,
+                         int row, int /* column */, const QModelIndex & /* parent */) const Q_DECL_OVERRIDE
+    { return row == 1; }
+
+    bool dropMimeData(const QMimeData *, Qt::DropAction,
+                      int row, int /* column */, const QModelIndex & /* parent */) Q_DECL_OVERRIDE
+    { return row == 1; }
+};
+
+void tst_QSortFilterProxyModel::forwardDropApi()
+{
+    QSortFilterProxyModel model;
+    model.setSourceModel(new DropTestModel(&model));
+    model.setFilterFixedString(QStringLiteral("Row1"));
+    QCOMPARE(model.rowCount(), 1);
+    QVERIFY(model.canDropMimeData(0, Qt::CopyAction, 0, 0, QModelIndex()));
+    QVERIFY(model.dropMimeData(0, Qt::CopyAction, 0, 0, QModelIndex()));
+}
+
 QTEST_MAIN(tst_QSortFilterProxyModel)
 #include "tst_qsortfilterproxymodel.moc"