Add a method to clear the data to QStandardItemModel

After the behavior of setItemData has been changed following QTBUG-45114,
QStandardItemModel was lacking an interface to clear all the data from a single index.

Task-number: QTBUG-69616
Change-Id: Ide0b5bb6358439fc42c474df8b044fbace6def8d
Reviewed-by: André Hartmann <aha_1980@gmx.de>
Reviewed-by: David Faure <david.faure@kdab.com>

2 files changed, 35 insertions, 0 deletions

diff --git a/src/gui/itemmodels/qstandarditemmodel.cpp b/src/gui/itemmodels/qstandarditemmodel.cpp
index 235bc5bd7d..a771bffa2f 100644
--- a/src/gui/itemmodels/qstandarditemmodel.cpp
+++ b/src/gui/itemmodels/qstandarditemmodel.cpp
@@ -931,6 +931,21 @@ void QStandardItem::setData(const QVariant &value, int role)
 }
 
 /*!
+    \since 5.12
+    Removes all the data from all roles previously set.
+    \sa data(), setData()
+*/
+void QStandardItem::clearData()
+{
+    Q_D(QStandardItem);
+    if (d->values.isEmpty())
+        return;
+    d->values.clear();
+    if (d->model)
+        d->model->d_func()->itemChanged(this, QVector<int>{});
+}
+
+/*!
     Returns the item's data for the given \a role, or an invalid
     QVariant if there is no data for the role.
 
@@ -2991,6 +3006,23 @@ bool QStandardItemModel::setData(const QModelIndex &index, const QVariant &value
 }
 
 /*!
+  \since 5.12
+  Removes the data stored in all the roles for the given \a index.
+  \sa setData(), data()
+*/
+bool QStandardItemModel::clearItemData(const QModelIndex &index)
+{
+    if (!checkIndex(index, CheckIndexOption::IndexIsValid))
+        return false;
+    Q_D(QStandardItemModel);
+    QStandardItem *item = d->itemFromIndex(index);
+    if (!item)
+        return false;
+    item->clearData();
+    return true;
+}
+
+/*!
   \reimp
 */
 bool QStandardItemModel::setHeaderData(int section, Qt::Orientation orientation, const QVariant &value, int role)
diff --git a/src/gui/itemmodels/qstandarditemmodel.h b/src/gui/itemmodels/qstandarditemmodel.h
index 827179b31d..a9ee25da75 100644
--- a/src/gui/itemmodels/qstandarditemmodel.h
+++ b/src/gui/itemmodels/qstandarditemmodel.h
@@ -69,6 +69,7 @@ public:
 
     virtual QVariant data(int role = Qt::UserRole + 1) const;
     virtual void setData(const QVariant &value, int role = Qt::UserRole + 1);
+    void clearData();
 
     inline QString text() const {
         return qvariant_cast<QString>(data(Qt::DisplayRole));
@@ -343,6 +344,8 @@ public:
 
     QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const override;
     bool setData(const QModelIndex &index, const QVariant &value, int role = Qt::EditRole) override;
+    // Qt 6: add override keyword
+    bool clearItemData(const QModelIndex &index);
 
     QVariant headerData(int section, Qt::Orientation orientation,
                         int role = Qt::DisplayRole) const override;