Auto-resize the main window.

If the summary widget is large, it gets a scrollbar. This looks really
weird, so prefer to grow the installer window instead. Discussed with
@sitter and settled on this solution.

ViewSteps can signal the ViewManager that they need more space (in pixels),
which may or may not be honored.

FIXES #778

src/calamares/CalamaresWindow.cpp

@@ -131,10 +131,8 @@ CalamaresWindow::CalamaresWindow( QWidget* parent )
             else
             {
                 if ( m_debugWindow )
-                {
                     m_debugWindow->deleteLater();
             }
-            }
         } );
     }
 
@@ -142,6 +140,19 @@ CalamaresWindow::CalamaresWindow( QWidget* parent )
     CalamaresUtils::unmarginLayout( mainLayout );
 
     Calamares::ViewManager* vm = Calamares::ViewManager::instance( this );
+    connect( vm, &Calamares::ViewManager::enlarge, this, &CalamaresWindow::enlarge );
 
     mainLayout->addWidget( vm->centralWidget() );
 }
+
+void
+CalamaresWindow::enlarge( QSize enlarge )
+{
+    auto mainGeometry = this->geometry();
+    QSize availableSize = qApp->desktop()->availableGeometry( this ).size();
+
+    auto h = qBound( 0, mainGeometry.height() + enlarge.height(), availableSize.height() );
+    auto w = this->size().width();
+
+    resize( w, h );
+}

src/calamares/CalamaresWindow.h

@@ -1,6 +1,7 @@
 /* === This file is part of Calamares - <http://github.com/calamares> ===
  *
  *   Copyright 2014-2015, Teo Mrnjavac <teo@kde.org>
+ *   Copyright 2017, Adriaan de Groot <groot@kde.org>
  *
  *   Calamares is free software: you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -37,6 +38,14 @@ public:
     CalamaresWindow( QWidget* parent = nullptr );
     virtual ~CalamaresWindow() {}
 
+public slots:
+    /**
+     * This asks the main window to grow by @p enlarge pixels, to accomodate
+     * larger-than-expected window contents. The enlargement may be silently
+     * ignored.
+     */
+    void enlarge( QSize enlarge );
+
 private:
     QPointer< Calamares::DebugWindow > m_debugWindow;
 };

src/libcalamaresui/ViewManager.cpp

@@ -109,9 +109,7 @@ ViewManager::ViewManager( QObject* parent )
                 qApp->quit();
         }
         else // Means we're at the end, no need to confirm.
-        {
             qApp->quit();
-        }
     } );
 
     connect( JobQueue::instance(), &JobQueue::failed,
@@ -150,11 +148,10 @@ ViewManager::insertViewStep( int before, ViewStep* step)
     m_steps.insert( before, step );
     QLayout* layout = step->widget()->layout();
     if ( layout )
-    {
         layout->setContentsMargins( 0, 0, 0, 0 );
-    }
     m_stack->insertWidget( before, step->widget() );
 
+    connect( step, &ViewStep::enlarge, this, &ViewManager::enlarge );
     connect( step, &ViewStep::nextStatusChanged,
              this, [this]( bool status )
     {
@@ -187,9 +184,7 @@ ViewManager::onInstallationFailed( const QString& message, const QString& detail
 
     QString text = "<p>" + message + "</p>";
     if ( !details.isEmpty() )
-    {
         text += "<p>" + details + "</p>";
-    }
     msgBox->setInformativeText( text );
 
     connect( msgBox, &QMessageBox::buttonClicked, qApp, &QApplication::quit );
@@ -263,9 +258,7 @@ ViewManager::next()
         }
     }
     else
-    {
         step->next();
-    }
 
     m_next->setEnabled( !executing && m_steps.at( m_currentStep )->isNextEnabled() );
     m_back->setEnabled( !executing && m_steps.at( m_currentStep )->isBackEnabled() );
@@ -292,9 +285,7 @@ ViewManager::back()
         emit currentStepChanged();
     }
     else if ( !step->isAtBeginning() )
-    {
         step->back();
-    }
     else return;
 
     m_next->setEnabled( m_steps.at( m_currentStep )->isNextEnabled() );

src/libcalamaresui/ViewManager.h

@@ -1,6 +1,7 @@
 /* === This file is part of Calamares - <http://github.com/calamares> ===
  *
  *   Copyright 2014-2015, Teo Mrnjavac <teo@kde.org>
+ *   Copyright 2017, Adriaan de Groot <groot@kde.org>
  *
  *   Calamares is free software: you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -111,6 +112,7 @@ public slots:
 
 signals:
     void currentStepChanged();
+    void enlarge( QSize enlarge ) const;  // See ViewStep::enlarge()
 
 private:
     explicit ViewManager( QObject* parent = nullptr );

src/libcalamaresui/viewpages/ViewStep.h

@@ -1,6 +1,7 @@
 /* === This file is part of Calamares - <http://github.com/calamares> ===
  *
  *   Copyright 2014-2015, Teo Mrnjavac <teo@kde.org>
+ *   Copyright 2017, Adriaan de Groot <groot@kde.org>
  *
  *   Calamares is free software: you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -93,7 +94,10 @@ public:
     virtual QList< job_ptr > jobs() const = 0;
 
     void setModuleInstanceKey( const QString& instanceKey );
-    QString moduleInstanceKey() const { return m_instanceKey; }
+    QString moduleInstanceKey() const
+    {
+        return m_instanceKey;
+    }
 
     virtual void setConfigurationMap( const QVariantMap& configurationMap );
 
@@ -101,6 +105,12 @@ signals:
     void nextStatusChanged( bool status );
     void done();
 
+    /* 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.
+     */
+    void enlarge( QSize enlarge ) const;
+
 protected:
     QString m_instanceKey;
 };

src/modules/summary/SummaryPage.cpp

@@ -1,6 +1,7 @@
 /* === This file is part of Calamares - <http://github.com/calamares> ===
  *
  *   Copyright 2014-2015, Teo Mrnjavac <teo@kde.org>
+ *   Copyright 2017, Adriaan de Groot <groot@kde.org>
  *
  *   Calamares is free software: you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -23,6 +24,7 @@
 #include "ExecutionViewStep.h"
 #include "utils/Retranslator.h"
 #include "utils/CalamaresUtilsGui.h"
+#include "utils/Logger.h"
 #include "ViewManager.h"
 
 #include <QBoxLayout>
@@ -96,6 +98,20 @@ SummaryPage::onActivate()
         itemBodyLayout->addSpacing( CalamaresUtils::defaultFontHeight() * 2 );
     }
     m_layout->addStretch();
+
+    m_scrollArea->setWidget( m_contentWidget );
+
+    auto summarySize = m_contentWidget->sizeHint();
+    if ( summarySize.height() > m_scrollArea->size().height() )
+    {
+        auto enlarge = 2 + summarySize.height() - m_scrollArea->size().height();
+        auto widgetSize = this->size();
+        widgetSize.setHeight( widgetSize.height() + enlarge );
+
+        cDebug() << "Summary widget is larger than viewport, enlarge by" << enlarge << "to" << widgetSize;
+
+        emit m_thisViewStep->enlarge( QSize( 0, enlarge ) );  // Only expand height
+    }
 }
 
 Calamares::ViewStepList
@@ -133,7 +149,6 @@ SummaryPage::createContentWidget()
     m_contentWidget = new QWidget;
     m_layout = new QVBoxLayout( m_contentWidget );
     CalamaresUtils::unmarginLayout( m_layout );
-    m_scrollArea->setWidget( m_contentWidget );
 }
 
 QLabel*