Don't call CppTypeHierarchyWidget::perform() twice

In case a Type Hierarchy widget isn't visible,
the CppIncludeHierarchyWidget::perform() is called
twice when requested from "Open Type Hierarchy" context menu.

The instances of CppIncludeHierarchyWidget class
are created only when Type Hierarchy item is selected
form the combobox, and are destroyed when different item
is selected. A call to:
NavigationWidget::activateSubWidget(Constants::TYPE_HIERARCHY_ID,
Side::Left) may be ignored (in case Type Hierarchy widget was
visible) or may recreate the widget and invoke
CppTypeHierarchyWidget::perform() for the first time
(in case when Type Hierarchy wasn't visible).
Just after this we emit typeHierarchyRequested(), which in turn
invokes perform() one more time unconditionally.

In order to fix it, we emit the signal typeHierarchyRequested()
first (which will invoke perform() only when the Type Hierarchy
widget was visible), and later call activateSubWidget(), which
invoke perform only when we are recreating a widget.

This shorten the freeze time for calculating big hierarchies,
like for ExtensionSystem::IPlugin, by 50%.

We do the same for CppIncludeHierarchyWidget.

Change-Id: If58fba4ba1dc32999d106fc2faa712e05442caf3
Reviewed-by: Eike Ziller <eike.ziller@qt.io>
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

0 files changed, 0 insertions, 0 deletions