CTK/Libs/Widgets/ctkCheckableHeaderView.h

/*=========================================================================

  Library:   CTK

  Copyright (c) Kitware Inc.

  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

      http://www.commontk.org/LICENSE

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  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.

=========================================================================*/
/*=========================================================================

   Program: ParaView
   Module:    $RCSfile: pqCheckableHeaderView.h,v $

   Copyright (c) 2005-2008 Sandia Corporation, Kitware Inc.
   All rights reserved.

   ParaView is a free software; you can redistribute it and/or modify it
   under the terms of the ParaView license version 1.2. 

   See License_v1.2.txt for the full ParaView license.
   A copy of this license can be obtained by contacting
   Kitware Inc.
   28 Corporate Drive
   Clifton Park, NY 12065
   USA

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

=========================================================================*/

#ifndef _ctkCheckableHeaderView_h
#define _ctkCheckableHeaderView_h

// Qt includes
#include <QHeaderView>

// CTK includes
#include <ctkPimpl.h>

#include "ctkWidgetsExport.h"

class ctkCheckableHeaderViewPrivate;

///
/// ctkCheckableHeaderView is a QHeaderView that can display a checkbox 
/// for any header section.
/// If propageteToItems, the check state of the header section is set to
/// all items in the header row/column of the QAbstractItemModel if the 
/// items are checkable.
/// ctkCheckableHeaderView also supports row/column sorting.
/// TBD: It should probably be a QSortFilterProxyModel that adds a checkability
/// data on top of the indexes.
class CTK_WIDGETS_EXPORT ctkCheckableHeaderView : public QHeaderView
{
  Q_OBJECT;
  Q_PROPERTY(bool forceCheckability READ forceCheckability WRITE setForceCheckability);
  Q_PROPERTY(int propagateDepth READ propagateDepth WRITE setPropagateDepth);
public:
  ctkCheckableHeaderView(Qt::Orientation orient, QWidget *parent=0);
  virtual ~ctkCheckableHeaderView();

  ///
  /// When setting the model, if PropagateToItems is true (by default), the check
  /// state of the checkable headers is updated from the check state of the items
  /// If you want to make sure of the check state of a header, after setting the
  /// (done by myView.setHeader(myCheckableHeaderView)), you can call
  /// myModel.setHeaderData(0, Qt::Horizontal, Qt::Checked, Qt::CheckStateRole)
  /// or myCheckableHeaderView->setCheckState(0, Qt::Checked)
  virtual void setModel(QAbstractItemModel *model);

  /// Reimplemented for internal reasons
  virtual void setRootIndex(const QModelIndex &index);

  /// 
  /// A section is checkable if its CheckStateRole data is non null. 
  /// One can access the same value through the model:
  /// model->headerData(orientation, section, Qt::CheckStateRole).isEmpty()
  bool isCheckable(int section)const;

  ///
  /// Utility function that returns the checkState of the section. 
  /// One can access the same value through the model:
  /// model->headerData(orientation, section, Qt::CheckStateRole)
  Qt::CheckState checkState(int section)const;

  ///
  /// Utility function that returns the checkState of the section. 
  /// One can access the same value through the model:
  /// model->headerData(orientation, section, Qt::CheckStateRole)
  bool checkState(int section,Qt::CheckState& checkState )const;

  ///
  ///  Used to listen for focus in/out events.
  /// \param object The object receiving the event.
  /// \param e Event specific data.
  /// \return
  ///   True if the event should be filtered out.
  virtual bool eventFilter(QObject *object, QEvent *e);

  /// How deep in the model(tree) do you want the check state to be propagated
  /// A value of -1 correspond to the deepest level of the model.
  /// -1 by default
  void setPropagateDepth(int depth);
  int  propagateDepth()const;
  
  void setForceCheckability(bool force);
  bool forceCheckability()const;

public slots:
  ///
  /// if the check state is PartiallyChecked, the section becomes Checked
  void toggleCheckState(int section);
  ///
  /// Warning, setting the check state automatically set the 
  /// header section checkable
  void setCheckState(int section, Qt::CheckState checkState);

private slots:
  void onHeaderDataChanged(Qt::Orientation orient, int first, int last);

  void onHeaderSectionInserted(const QModelIndex &parent, int first, int last);
  inline void updateHeaderPixmaps();

  void onDataChanged(const QModelIndex& topLeft, const QModelIndex& bottomRight);
  void updateHeadersFromItems();
  
protected:
  virtual void updateHeaderPixmaps(int first, int last);
  virtual void initStyleSectionOption(QStyleOptionHeader *option, int section, QRect rect)const;
  virtual void mousePressEvent(QMouseEvent *e);
  virtual void mouseReleaseEvent(QMouseEvent *e);
  bool isPointInCheckBox(int section, QPoint pos)const;

protected:
  QScopedPointer<ctkCheckableHeaderViewPrivate> d_ptr;

private:
  Q_DECLARE_PRIVATE(ctkCheckableHeaderView);
  Q_DISABLE_COPY(ctkCheckableHeaderView);
};

//-----------------------------------------------------------------------------
void ctkCheckableHeaderView::updateHeaderPixmaps()
{
  this->updateHeaderPixmaps(0, this->count()-1);
}

#endif