Hide editing controls in multi-selection mode

Don’t show (albeit disabled) editing controls if the user selects
multiple items. Instead, hide things like character counter, tags or
the fuzzy toggle, and clear texts.

This is still not ideal UI, but is better than before.

src/editing_area.cpp

@@ -739,8 +739,9 @@ void EditingArea::UpdateEditingUIForCatalog(CatalogPtr catalog)
     else
         m_labelSource->SetLabel(_("Source text"));
 
+    m_fuzzyToggleNeeded = m_fuzzy && catalog->HasCapability(Catalog::Cap::FuzzyTranslations);
     if (m_fuzzy)
-        m_fuzzy->Show(catalog->HasCapability(Catalog::Cap::FuzzyTranslations));
+        m_fuzzy->Show(m_fuzzyToggleNeeded);
 
     RecreatePluralTextCtrls(catalog);
 }
@@ -876,14 +877,34 @@ void EditingArea::ShowPart(wxWindow *part, bool show)
 
 void EditingArea::SetSingleSelectionMode()
 {
-    if (!IsThisEnabled())
-        Enable();  // in case of previous multiple selection
+    if (m_isSingleSelection)
+        return;
+    m_isSingleSelection = true;
+
+    if (m_fuzzy)
+        m_fuzzy->Show(m_fuzzyToggleNeeded);
+    m_charCounter->Show();
+
+    Enable();
 }
 
 
 void EditingArea::SetMultipleSelectionMode()
 {
+    if (!m_isSingleSelection)
+        return;
+    m_isSingleSelection = false;
+
     // TODO: Show better UI
+
+    if (m_fuzzy)
+        m_fuzzy->Hide();
+    m_charCounter->Hide();
+    ShowPluralFormUI(false);
+    ShowPart(m_tagIdOrContext, false);
+    ShowPart(m_tagFormat, false);
+    m_textOrig->Clear();
+    m_textTrans->Clear();
     Disable();
 }
 

src/editing_area.h

@@ -137,6 +137,9 @@ class EditingArea : public wxPanel
 
     PoeditListCtrl *m_associatedList;
 
+    bool m_isSingleSelection = true;
+    bool m_fuzzyToggleNeeded = true;
+
     bool m_dontAutoclearFuzzyStatus;
 
     SourceTextCtrl *m_textOrig, *m_textOrigPlural;