QmlDesigner: only reset model if it is necessary

- it was 3 times for one update call

Change-Id: Ieed98fc42a2e28487164602549eb11b87f6f2b18
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@theqtcompany.com>

src/plugins/qmldesigner/components/itemlibrary/itemlibrarymodel.cpp

@@ -118,7 +118,10 @@ void ItemLibraryModel::setSearchText(const QString &searchText)
         m_searchText = lowerSearchText;
         emit searchTextChanged();
 
-        updateVisibility();
+        bool changed = false;
+        updateVisibility(&changed);
+        if (changed)
+            dataChanged(QModelIndex(), QModelIndex());
     }
 }
 
@@ -137,8 +140,7 @@ void ItemLibraryModel::update(ItemLibraryInfo *itemLibraryInfo, Model *model)
     if (!model)
         return;
 
-    QMap<QString, int> sections;
-
+    beginResetModel();
     clearSections();
 
     QStringList imports;
@@ -156,22 +158,22 @@ void ItemLibraryModel::update(ItemLibraryInfo *itemLibraryInfo, Model *model)
                      || model->hasImport(entryToImport(entry), true, true))) {
             QString itemSectionName = entry.category();
             ItemLibrarySection *sectionModel = sectionByName(itemSectionName);
-            ItemLibraryItem *item;
 
             if (sectionModel == 0) {
                 sectionModel = new ItemLibrarySection(itemSectionName, this);
                 m_sections.append(sectionModel);
             }
 
-            item = new ItemLibraryItem(sectionModel);
+            ItemLibraryItem *item = new ItemLibraryItem(sectionModel);
             item->setItemLibraryEntry(entry);
             sectionModel->addSectionEntry(item);
         }
     }
 
     sortSections();
-    resetModel();
-    updateVisibility();
+    bool changed = false;
+    updateVisibility(&changed);
+    endResetModel();
 }
 
 QMimeData *ItemLibraryModel::getMimeData(const ItemLibraryEntry &itemLibraryEntry)
@@ -195,10 +197,8 @@ QList<ItemLibrarySection *> ItemLibraryModel::sections() const
 
 void ItemLibraryModel::clearSections()
 {
-    beginResetModel();
     qDeleteAll(m_sections);
     m_sections.clear();
-    endResetModel();
 }
 
 void ItemLibraryModel::registerQmlTypes()
@@ -217,22 +217,17 @@ ItemLibrarySection *ItemLibraryModel::sectionByName(const QString &sectionName)
     return 0;
 }
 
-void ItemLibraryModel::updateVisibility()
+void ItemLibraryModel::updateVisibility(bool *changed)
 {
-    bool changed = false;
-
     foreach (ItemLibrarySection *itemLibrarySection, m_sections) {
         QString sectionSearchText = m_searchText;
 
         bool sectionChanged = false;
         bool sectionVisibility = itemLibrarySection->updateSectionVisibility(sectionSearchText,
                                                                              &sectionChanged);
-        changed |= sectionChanged;
-        changed |= itemLibrarySection->setVisible(sectionVisibility);
+        *changed |= sectionChanged;
+        *changed |= itemLibrarySection->setVisible(sectionVisibility);
     }
-
-    if (changed)
-        resetModel();
 }
 
 void ItemLibraryModel::addRoleNames()
@@ -245,12 +240,6 @@ void ItemLibraryModel::addRoleNames()
     }
 }
 
-void ItemLibraryModel::resetModel()
-{
-    beginResetModel();
-    endResetModel();
-}
-
 void ItemLibraryModel::sortSections()
 {
     auto sectionSort = [](ItemLibrarySection *first, ItemLibrarySection *second) {

src/plugins/qmldesigner/components/itemlibrary/itemlibrarymodel.h

@@ -79,9 +79,8 @@ signals:
     void searchTextChanged();
 
 private: // functions
-    void updateVisibility();
+    void updateVisibility(bool *changed);
     void addRoleNames();
-    void resetModel();
     void sortSections();