QcScrollArea.cpp

/************************************************************************
*
* Copyright 2010-2012 Jakob Leben (jakob.leben@gmail.com)
*
* This file is part of SuperCollider Qt GUI.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program.  If not, see <http://www.gnu.org/licenses/>.
*
************************************************************************/

#include "QcScrollArea.h"
#include "../QcWidgetFactory.h"

#include <QLayout>
#include <QScrollBar>
#include <QEvent>
#include <QChildEvent>
#include <QApplication>

class QcScrollWidgetFactory : public QcWidgetFactory<QcScrollWidget>
{
protected:
  virtual void initialize( QWidgetProxy *p, QcScrollWidget *w )
  {
    QObject::connect( w, SIGNAL(painting(QPainter*)),
                      p, SLOT(customPaint(QPainter*)) );
  }
};

QC_DECLARE_FACTORY( QcScrollWidget, QcScrollWidgetFactory );

QcScrollWidget::QcScrollWidget( QWidget *parent ) : QcCanvas( parent )
{
  setSizePolicy( QSizePolicy::Minimum, QSizePolicy::Minimum );
  setAttribute(Qt::WA_AcceptTouchEvents);
}

QSize QcScrollWidget::sizeHint() const
{
  QRect r = childrenRect();
  QSize sz( r.x() + r.width(), r.y() + r.height() );
  return sz;
}

bool QcScrollWidget::event ( QEvent * e ) {
  int t = e->type();
  if( t == QEvent::ChildAdded ) {
    QChildEvent *ce = static_cast<QChildEvent*>(e);
    ce->child()->installEventFilter( this );
  }
  else if( t == QEvent::ChildRemoved ) {
    updateGeometry();
  }

  return QWidget::event( e );
}

bool QcScrollWidget::eventFilter ( QObject * watched, QEvent * event ) {
  Q_UNUSED( watched );

  switch( event->type() ) {
    case QEvent::Resize:
    case QEvent::Move:
    case QEvent::Show:
    case QEvent::Hide:
      updateGeometry();
      break;
    default:
      return false;
  }

  return false;
}



QC_DECLARE_QWIDGET_FACTORY(QcScrollArea);

QcScrollArea::QcScrollArea()
{
  connect( horizontalScrollBar(), SIGNAL(actionTriggered(int)),
           this, SIGNAL(scrolled()) );
  connect( verticalScrollBar(), SIGNAL(actionTriggered(int)),
           this, SIGNAL(scrolled()) );
}

void QcScrollArea::setWidget( QObjectProxy *proxy )
{
  QWidget *w = qobject_cast<QWidget*>( proxy->object() );
  if( !w ) {
    qcErrorMsg( "QcScrollArea::setCanvas: given proxy does not contain a valid widget." );
    return;
  }
  QScrollArea::setWidget( w );
  setWidgetResizable( true );
}

void QcScrollArea::addChild( QWidget* w )
{
  if( widget() )
    w->setParent( widget() );
}

QRectF QcScrollArea::innerBounds() const {
  QSize vs = viewport()->size();
  if( !widget() ) return QRectF(0,0,vs.width(),vs.height());
  QSize cs = widget()->size();
  return QRectF(0, 0,
                qMax( vs.width(), cs.width() ),
                qMax( vs.height(), cs.height() ) );
}

void QcScrollArea::setHasBorder( bool b ) {
  if( b )
    QFrame::setFrameShape( QFrame::StyledPanel );
  else
    QFrame::setFrameShape( QFrame::NoFrame );
}

QPointF QcScrollArea::visibleOrigin() const
{
  QWidget *w = widget();
  return ( w != 0 ? widget()->mapFromParent( QPoint(0,0) ) : QPoint(0,0) );
}

void QcScrollArea::setVisibleOrigin( const QPointF &pt )
{
  if (horizontalScrollBar()->maximum() < pt.x())
    horizontalScrollBar()->setMaximum(pt.x());
  if (verticalScrollBar()->maximum() < pt.y())
    verticalScrollBar()->setMaximum(pt.y());
  
  horizontalScrollBar()->setValue( pt.x() );
  verticalScrollBar()->setValue( pt.y() );
}