animation.h Example File | Qt Widgets 5.6

Qt 5.6 | Qt Widgets | Easing Curves Example | animation.h Example File

Qt 5.6.2 Reference Documentation

# animation.h Example File

animation/easing/animation.h

      /****************************************************************************
      **
      ** Copyright (C) 2015 The Qt Company Ltd.
      ** Contact: http://www.qt.io/licensing/
      **
      ** This file is part of the QtCore module of the Qt Toolkit.
      **
      ** $QT_BEGIN_LICENSE:BSD$
      ** You may use this file under the terms of the BSD license as follows:
      **
      ** "Redistribution and use in source and binary forms, with or without
      ** modification, are permitted provided that the following conditions are
      ** met:
      **   * Redistributions of source code must retain the above copyright
      **     notice, this list of conditions and the following disclaimer.
      **   * Redistributions in binary form must reproduce the above copyright
      **     notice, this list of conditions and the following disclaimer in
      **     the documentation and/or other materials provided with the
      **     distribution.
      **   * Neither the name of The Qt Company Ltd nor the names of its
      **     contributors may be used to endorse or promote products derived
      **     from this software without specific prior written permission.
      **
      **
      ** 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 COPYRIGHT
      ** OWNER 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."
      **
      ** $QT_END_LICENSE$
      **
      ****************************************************************************/

      #ifndef ANIMATION_H
      #define ANIMATION_H

      #include <QtWidgets>

      #include <QtCore/qpropertyanimation.h>

      class Animation : public QPropertyAnimation {
      public:
          enum PathType {
              LinearPath,
              CirclePath,
              NPathTypes
          };
          Animation(QObject *target, const QByteArray &prop)
              : QPropertyAnimation(target, prop)
          {
              setPathType(LinearPath);
          }

          void setPathType(PathType pathType)
          {
              if (pathType >= NPathTypes)
                  qWarning("Unknown pathType %d", pathType);

              m_pathType = pathType;
              m_path = QPainterPath();
          }

          void updateCurrentTime(int currentTime) Q_DECL_OVERRIDE
          {
              if (m_pathType == CirclePath) {
                  if (m_path.isEmpty()) {
                      QPointF to = endValue().toPointF();
                      QPointF from = startValue().toPointF();
                      m_path.moveTo(from);
                      m_path.addEllipse(QRectF(from, to));
                  }
                  int dura = duration();
                  const qreal progress = ((dura == 0) ? 1 : ((((currentTime - 1) % dura) + 1) / qreal(dura)));

                  qreal easedProgress = easingCurve().valueForProgress(progress);
                  if (easedProgress > 1.0) {
                      easedProgress -= 1.0;
                  } else if (easedProgress < 0) {
                      easedProgress += 1.0;
                  }
                  QPointF pt = m_path.pointAtPercent(easedProgress);
                  updateCurrentValue(pt);
                  emit valueChanged(pt);
              } else {
                  QPropertyAnimation::updateCurrentTime(currentTime);
              }
          }

          QPainterPath m_path;
          PathType m_pathType;
      };

      #endif // ANIMATION_H