[libcalamaresui] Rename enlarge()

- rename enlarge to ensureSize() and change the meaning from
  "make this much bigger" to "make sure this is displayed",
  which is easier on the caller to calculate.

src/calamares/CalamaresWindow.cpp

@@ -310,7 +310,7 @@ CalamaresWindow::CalamaresWindow( QWidget* parent )
     m_viewManager = Calamares::ViewManager::instance( this );
     if ( branding->windowExpands() )
     {
-        connect( m_viewManager, &Calamares::ViewManager::enlarge, this, &CalamaresWindow::enlarge );
+        connect( m_viewManager, &Calamares::ViewManager::ensureSize, this, &CalamaresWindow::ensureSize );
     }
     // NOTE: Although the ViewManager has a signal cancelEnabled() that
     //       signals when the state of the cancel button changes (in
@@ -356,12 +356,19 @@ CalamaresWindow::CalamaresWindow( QWidget* parent )
 }
 
 void
-CalamaresWindow::enlarge( QSize enlarge )
+CalamaresWindow::ensureSize( QSize size )
 {
     auto mainGeometry = this->geometry();
     QSize availableSize = qApp->desktop()->availableGeometry( this ).size();
 
-    auto h = qBound( 0, mainGeometry.height() + enlarge.height(), availableSize.height() );
+    // We only care about vertical sizes that are big enough
+    int embiggenment = qMax( 0, size.height() - m_viewManager->centralWidget()->size().height() );
+    if ( embiggenment < 6 )
+    {
+        return;
+    }
+
+    auto h = qBound( 0, mainGeometry.height() + embiggenment, availableSize.height() );
     auto w = this->size().width();
 
     resize( w, h );

src/calamares/CalamaresWindow.h

@@ -41,11 +41,11 @@ public:
 
 public slots:
     /**
-     * This asks the main window to grow by @p enlarge pixels, to accomodate
+     * This asks the main window to grow to accomodate @p size pixels, to accomodate
      * larger-than-expected window contents. The enlargement may be silently
      * ignored.
      */
-    void enlarge( QSize enlarge );
+    void ensureSize( QSize size );
 
 protected:
     virtual void closeEvent( QCloseEvent* e ) override;

src/libcalamaresui/ViewManager.cpp

@@ -118,7 +118,7 @@ ViewManager::insertViewStep( int before, ViewStep* step )
 {
     emit beginInsertRows( QModelIndex(), before, before );
     m_steps.insert( before, step );
-    connect( step, &ViewStep::enlarge, this, &ViewManager::enlarge );
+    connect( step, &ViewStep::ensureSize, this, &ViewManager::ensureSize );
     connect( step, &ViewStep::nextStatusChanged, this, &ViewManager::updateNextStatus );
 
     if ( !step->widget() )

src/libcalamaresui/ViewManager.h

@@ -195,7 +195,7 @@ public Q_SLOTS:
 
 signals:
     void currentStepChanged();
-    void enlarge( QSize enlarge ) const;  // See ViewStep::enlarge()
+    void ensureSize( QSize size ) const;  // See ViewStep::ensureSize()
     void cancelEnabled( bool enabled ) const;
 
     void nextEnabledChanged( bool ) const;

src/libcalamaresui/viewpages/ViewStep.h

@@ -149,10 +149,12 @@ signals:
     void nextStatusChanged( bool status );
 
     /* Emitted when the viewstep thinks it needs more space than is currently
-     * available for display. @p enlarge is the requested additional space,
-     * e.g. 24px vertical. This request may be silently ignored.
+     * available for display. @p size is the requested space, that is needed
+     * to display the entire page.
+     *
+     * This request may be silently ignored.
      */
-    void enlarge( QSize enlarge ) const;
+    void ensureSize( QSize enlarge ) const;
 
 protected:
     Calamares::ModuleSystem::InstanceKey m_instanceKey;

src/modules/locale/LocaleViewStep.cpp

@@ -73,6 +73,8 @@ LocaleViewStep::setUpPage()
     m_actualWidget->init( m_startingTimezone.first, m_startingTimezone.second, m_localeGenPath );
     m_widget->layout()->addWidget( m_actualWidget );
 
+    ensureSize( m_actualWidget->sizeHint() );
+
     m_nextEnabled = true;
     emit nextStatusChanged( m_nextEnabled );
 }

src/modules/summary/SummaryPage.cpp

@@ -124,7 +124,7 @@ SummaryPage::onActivate()
 
         cDebug() << "Summary widget is larger than viewport, enlarge by" << enlarge << "to" << widgetSize;
 
-        emit m_thisViewStep->enlarge( QSize( 0, enlarge ) );  // Only expand height
+        emit m_thisViewStep->ensureSize( widgetSize );  // Only expand height
     }
 }