QTreeWidget: Keep items hidden even if their parents are reparented

When an item is explicitly hidden, then it should stay that way even if
its parent is reparented. The item itself needs to be explicitly shown
for it to be made visible.

Task-number: QTBUG-54843
Change-Id: I0c6eea9a936f82d5874e3246292bd16365440411
Reviewed-by: Christian Ehrlicher <ch.ehrlicher@gmx.de>
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>

1 files changed, 38 insertions, 1 deletions

diff --git a/src/widgets/itemviews/qtreewidget.cpp b/src/widgets/itemviews/qtreewidget.cpp
index 2578fa0958..d0728b1af2 100644
--- a/src/widgets/itemviews/qtreewidget.cpp
+++ b/src/widgets/itemviews/qtreewidget.cpp
@@ -1001,7 +1001,6 @@ void QTreeModel::timerEvent(QTimerEvent *ev)
 */
 
 /*!
-  \fn void QTreeWidgetItem::setHidden(bool hide)
   \since 4.2
 
   Hides the item if \a hide is true, otherwise shows the item.
@@ -1012,6 +1011,14 @@ void QTreeModel::timerEvent(QTimerEvent *ev)
   \sa isHidden()
 */
 
+void QTreeWidgetItem::setHidden(bool ahide)
+{
+    if (view) {
+        view->setItemHidden(this, ahide);
+        d->hidden = ahide;
+    }
+}
+
 /*!
   \fn bool QTreeWidgetItem::isHidden() const
   \since 4.2
@@ -1021,6 +1028,11 @@ void QTreeModel::timerEvent(QTimerEvent *ev)
   \sa setHidden()
 */
 
+bool QTreeWidgetItem::isHidden() const
+{
+    return (view ? d->hidden : false);
+}
+
 /*!
   \fn void QTreeWidgetItem::setExpanded(bool expand)
   \since 4.2
@@ -1648,6 +1660,25 @@ void QTreeWidgetItem::setFlags(Qt::ItemFlags flags)
     itemChanged();
 }
 
+void QTreeWidgetItemPrivate::updateHiddenStatus(QTreeWidgetItem *item, bool inserting)
+{
+    QTreeModel *model = (item->view ? qobject_cast<QTreeModel*>(item->view->model()) : 0);
+    if (!model)
+        return;
+    QStack<QTreeWidgetItem *> parents;
+    parents.push(item);
+    while (!parents.isEmpty()) {
+        QTreeWidgetItem *parent = parents.pop();
+        QModelIndex index = model->index(parent, 0);
+        if (parent->d->hidden)
+            item->view->setRowHidden(index.row(), index.parent(), inserting);
+        for (int i = 0; i < parent->children.count(); ++i) {
+            QTreeWidgetItem *child = parent->children.at(i);
+            parents.push(child);
+        }
+    }
+}
+
 void QTreeWidgetItemPrivate::propagateDisabled(QTreeWidgetItem *item)
 {
     Q_ASSERT(item);
@@ -1937,6 +1968,7 @@ void QTreeWidgetItem::insertChild(int index, QTreeWidgetItem *child)
                 stack.push(i->children.at(c));
         }
         children.insert(index, child);
+        d->updateHiddenStatus(child, true);
         model->endInsertItems();
         model->skipPendingSort = wasSkipSort;
     } else {
@@ -1974,6 +2006,7 @@ QTreeWidgetItem *QTreeWidgetItem::takeChild(int index)
     }
     if (index >= 0 && index < children.count()) {
         if (model) model->beginRemoveItems(this, index, 1);
+        d->updateHiddenStatus(children.at(index), false);
         QTreeWidgetItem *item = children.takeAt(index);
         item->par = 0;
         QStack<QTreeWidgetItem*> stack;
@@ -2052,6 +2085,7 @@ void QTreeWidgetItem::insertChildren(int index, const QList<QTreeWidgetItem*> &c
             this->children.insert(index + n, child);
             if (child->par)
                 d->propagateDisabled(child);
+            d->updateHiddenStatus(child, true);
         }
         if (model) model->endInsertItems();
     }
@@ -3099,6 +3133,8 @@ bool QTreeWidget::isItemHidden(const QTreeWidgetItem *item) const
 */
 void QTreeWidget::setItemHidden(const QTreeWidgetItem *item, bool hide)
 {
+    if (!item)
+        return;
     Q_D(QTreeWidget);
     if (item == d->treeModel()->headerItem) {
         header()->setHidden(hide);
@@ -3106,6 +3142,7 @@ void QTreeWidget::setItemHidden(const QTreeWidgetItem *item, bool hide)
         const QModelIndex index = d->index(item);
         setRowHidden(index.row(), index.parent(), hide);
     }
+    item->d->hidden = hide;
 }
 
 /*!