add a collapsing row hook

Change-Id: I83d690715a9e427d23b3f2316fd114c037487d54
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/89841
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolanm@redhat.com>

3 files changed, 33 insertions, 3 deletions

diff --git a/include/vcl/weld.hxx b/include/vcl/weld.hxx
index 7f3463611a4d..75c38262c426 100644
--- a/include/vcl/weld.hxx
+++ b/include/vcl/weld.hxx
@@ -718,6 +718,8 @@ protected:
     Link<const std::pair<const TreeIter&, OUString>&, bool> m_aEditingDoneHdl;
     // if handler returns false, the expansion of the row is refused
     Link<const TreeIter&, bool> m_aExpandingHdl;
+    // if handler returns false, the collapse of the row is refused
+    Link<const TreeIter&, bool> m_aCollapsingHdl;
     Link<TreeView&, void> m_aVisibleRangeChangedHdl;
     Link<TreeView&, void> m_aModelChangedHdl;
     // if handler returns true, then menu has been show and event is consumed
@@ -736,6 +738,10 @@ protected:
     {
         return !m_aExpandingHdl.IsSet() || m_aExpandingHdl.Call(rIter);
     }
+    bool signal_collapsing(const TreeIter& rIter)
+    {
+        return !m_aCollapsingHdl.IsSet() || m_aCollapsingHdl.Call(rIter);
+    }
     void signal_visible_range_changed() { m_aVisibleRangeChangedHdl.Call(*this); }
     void signal_model_changed() { m_aModelChangedHdl.Call(*this); }
 
@@ -962,6 +968,7 @@ public:
         = 0;
 
     void connect_expanding(const Link<const TreeIter&, bool>& rLink) { m_aExpandingHdl = rLink; }
+    void connect_collapsing(const Link<const TreeIter&, bool>& rLink) { m_aCollapsingHdl = rLink; }
 
     // rStartLink returns true to allow editing, false to disallow
     // rEndLink returns true to accept the edit, false to reject
diff --git a/vcl/source/app/salvtables.cxx b/vcl/source/app/salvtables.cxx
index 14da859c1a0c..e4aafd793bba 100644
--- a/vcl/source/app/salvtables.cxx
+++ b/vcl/source/app/salvtables.cxx
@@ -4227,7 +4227,7 @@ public:
     virtual void collapse_row(const weld::TreeIter& rIter) override
     {
         const SalInstanceTreeIter& rVclIter = static_cast<const SalInstanceTreeIter&>(rIter);
-        if (m_xTreeView->IsExpanded(rVclIter.iter))
+        if (m_xTreeView->IsExpanded(rVclIter.iter) && signal_collapsing(rIter))
             m_xTreeView->Collapse(rVclIter.iter);
     }
 
@@ -4676,19 +4676,22 @@ IMPL_LINK(SalInstanceTreeView, HeaderBarClickedHdl, HeaderBar*, pHeaderBar, void
 IMPL_LINK_NOARG(SalInstanceTreeView, ExpandingHdl, SvTreeListBox*, bool)
 {
     SvTreeListEntry* pEntry = m_xTreeView->GetHdlEntry();
+    SalInstanceTreeIter aIter(pEntry);
+
     if (m_xTreeView->IsExpanded(pEntry))
     {
         //collapsing;
-        return true;
+        return signal_collapsing(aIter);
     }
 
+    // expanding
+
     // if there's a preexisting placeholder child, required to make this
     // potentially expandable in the first place, now we remove it
     SvTreeListEntry* pPlaceHolder = GetPlaceHolderChild(pEntry);
     if (pPlaceHolder)
         m_xTreeView->RemoveEntry(pPlaceHolder);
 
-    SalInstanceTreeIter aIter(pEntry);
     bool bRet = signal_expanding(aIter);
 
     //expand disallowed, restore placeholder
diff --git a/vcl/unx/gtk3/gtk3gtkinst.cxx b/vcl/unx/gtk3/gtk3gtkinst.cxx
index 6901202c9796..0720a6833b57 100644
--- a/vcl/unx/gtk3/gtk3gtkinst.cxx
+++ b/vcl/unx/gtk3/gtk3gtkinst.cxx
@@ -8604,6 +8604,7 @@ private:
     gulong m_nChangedSignalId;
     gulong m_nRowActivatedSignalId;
     gulong m_nTestExpandRowSignalId;
+    gulong m_nTestCollapseRowSignalId;
     gulong m_nVAdjustmentChangedSignalId;
     gulong m_nRowDeletedSignalId;
     gulong m_nRowInsertedSignalId;
@@ -8801,6 +8802,12 @@ private:
         return !pThis->signal_test_expand_row(*iter);
     }
 
+    static gboolean signalTestCollapseRow(GtkTreeView*, GtkTreeIter* iter, GtkTreePath*, gpointer widget)
+    {
+        GtkInstanceTreeView* pThis = static_cast<GtkInstanceTreeView*>(widget);
+        return !pThis->signal_test_collapse_row(*iter);
+    }
+
     bool child_is_placeholder(GtkInstanceTreeIter& rGtkIter) const
     {
         bool bPlaceHolder = false;
@@ -8843,6 +8850,17 @@ private:
         return bRet;
     }
 
+    bool signal_test_collapse_row(GtkTreeIter& iter)
+    {
+        disable_notify_events();
+
+        GtkInstanceTreeIter aIter(iter);
+        bool bRet = signal_collapsing(aIter);
+
+        enable_notify_events();
+        return bRet;
+    }
+
     static void signalCellToggled(GtkCellRendererToggle* pCell, const gchar *path, gpointer widget)
     {
         GtkInstanceTreeView* pThis = static_cast<GtkInstanceTreeView*>(widget);
@@ -9134,6 +9152,7 @@ public:
                              G_CALLBACK(signalChanged), this))
         , m_nRowActivatedSignalId(g_signal_connect(pTreeView, "row-activated", G_CALLBACK(signalRowActivated), this))
         , m_nTestExpandRowSignalId(g_signal_connect(pTreeView, "test-expand-row", G_CALLBACK(signalTestExpandRow), this))
+        , m_nTestCollapseRowSignalId(g_signal_connect(pTreeView, "test-collapse-row", G_CALLBACK(signalTestCollapseRow), this))
         , m_nVAdjustmentChangedSignalId(0)
         , m_nPopupMenuSignalId(g_signal_connect(pTreeView, "popup-menu", G_CALLBACK(signalPopupMenu), this))
         , m_nKeyPressSignalId(g_signal_connect(pTreeView, "key-press-event", G_CALLBACK(signalKeyPress), this))
@@ -10643,6 +10662,7 @@ public:
             g_signal_handler_disconnect(pVAdjustment, m_nVAdjustmentChangedSignalId);
         }
 
+        g_signal_handler_disconnect(m_pTreeView, m_nTestCollapseRowSignalId);
         g_signal_handler_disconnect(m_pTreeView, m_nTestExpandRowSignalId);
         g_signal_handler_disconnect(m_pTreeView, m_nRowActivatedSignalId);
         g_signal_handler_disconnect(gtk_tree_view_get_selection(m_pTreeView), m_nChangedSignalId);