Qt Animation Framework

With the advent of Qt 4.6, the implementation of animation in the project has been simplified to a minimum.

In the event that you need to animate component properties, Qt 4.6 offers to use the QPropertyAnimation class. Here is an example of a widget's resize animation:

#include <QWidget> #include <QPropertyAnimation> #include <QEasingCurve> class MyWidget : public QWidget { public : MyWidget(QObject* parent = 0); // MyWidget fields and methods public slots: void startAnimation(); private : QPropertyAnimation* _propertyAnimation; }; * This source code was highlighted with Source Code Highlighter .

1. #include <QWidget> #include <QPropertyAnimation> #include <QEasingCurve> class MyWidget : public QWidget { public : MyWidget(QObject* parent = 0); // MyWidget fields and methods public slots: void startAnimation(); private : QPropertyAnimation* _propertyAnimation; }; * This source code was highlighted with Source Code Highlighter .
2. #include <QWidget> #include <QPropertyAnimation> #include <QEasingCurve> class MyWidget : public QWidget { public : MyWidget(QObject* parent = 0); // MyWidget fields and methods public slots: void startAnimation(); private : QPropertyAnimation* _propertyAnimation; }; * This source code was highlighted with Source Code Highlighter .
3. #include <QWidget> #include <QPropertyAnimation> #include <QEasingCurve> class MyWidget : public QWidget { public : MyWidget(QObject* parent = 0); // MyWidget fields and methods public slots: void startAnimation(); private : QPropertyAnimation* _propertyAnimation; }; * This source code was highlighted with Source Code Highlighter .
5. #include <QWidget> #include <QPropertyAnimation> #include <QEasingCurve> class MyWidget : public QWidget { public : MyWidget(QObject* parent = 0); // MyWidget fields and methods public slots: void startAnimation(); private : QPropertyAnimation* _propertyAnimation; }; * This source code was highlighted with Source Code Highlighter .
6. #include <QWidget> #include <QPropertyAnimation> #include <QEasingCurve> class MyWidget : public QWidget { public : MyWidget(QObject* parent = 0); // MyWidget fields and methods public slots: void startAnimation(); private : QPropertyAnimation* _propertyAnimation; }; * This source code was highlighted with Source Code Highlighter .
7. #include <QWidget> #include <QPropertyAnimation> #include <QEasingCurve> class MyWidget : public QWidget { public : MyWidget(QObject* parent = 0); // MyWidget fields and methods public slots: void startAnimation(); private : QPropertyAnimation* _propertyAnimation; }; * This source code was highlighted with Source Code Highlighter .
8. #include <QWidget> #include <QPropertyAnimation> #include <QEasingCurve> class MyWidget : public QWidget { public : MyWidget(QObject* parent = 0); // MyWidget fields and methods public slots: void startAnimation(); private : QPropertyAnimation* _propertyAnimation; }; * This source code was highlighted with Source Code Highlighter .
9. #include <QWidget> #include <QPropertyAnimation> #include <QEasingCurve> class MyWidget : public QWidget { public : MyWidget(QObject* parent = 0); // MyWidget fields and methods public slots: void startAnimation(); private : QPropertyAnimation* _propertyAnimation; }; * This source code was highlighted with Source Code Highlighter .
10. #include <QWidget> #include <QPropertyAnimation> #include <QEasingCurve> class MyWidget : public QWidget { public : MyWidget(QObject* parent = 0); // MyWidget fields and methods public slots: void startAnimation(); private : QPropertyAnimation* _propertyAnimation; }; * This source code was highlighted with Source Code Highlighter .
11. #include <QWidget> #include <QPropertyAnimation> #include <QEasingCurve> class MyWidget : public QWidget { public : MyWidget(QObject* parent = 0); // MyWidget fields and methods public slots: void startAnimation(); private : QPropertyAnimation* _propertyAnimation; }; * This source code was highlighted with Source Code Highlighter .
12. #include <QWidget> #include <QPropertyAnimation> #include <QEasingCurve> class MyWidget : public QWidget { public : MyWidget(QObject* parent = 0); // MyWidget fields and methods public slots: void startAnimation(); private : QPropertyAnimation* _propertyAnimation; }; * This source code was highlighted with Source Code Highlighter .
13. #include <QWidget> #include <QPropertyAnimation> #include <QEasingCurve> class MyWidget : public QWidget { public : MyWidget(QObject* parent = 0); // MyWidget fields and methods public slots: void startAnimation(); private : QPropertyAnimation* _propertyAnimation; }; * This source code was highlighted with Source Code Highlighter .

#include <QWidget> #include <QPropertyAnimation> #include <QEasingCurve> class MyWidget : public QWidget { public : MyWidget(QObject* parent = 0); // MyWidget fields and methods public slots: void startAnimation(); private : QPropertyAnimation* _propertyAnimation; }; * This source code was highlighted with Source Code Highlighter .

1. MyWidget :: MyWidget (QObject * parent): QWidget (parent) {
2. // Widget initialization
3. _propertyAnimation = new QPropertyAnimation ( this , "geometry" );
4. _propertyAnimation-> setDuration (1000);
5. _propertyAnimation-> setEasingCurve (QEasingCurve :: OutCubic);
6. }
8. void MyWidget :: startAnimation () {
9. QRectF firstPosition;
10. QRectF endPosition;
11. // Initializing first and end values
12. _propertyAnimation-> setFirstValue (firstPosition);
13. _propertyAnimation-> setEndValue (endPosition);
14. _propertyAnimation-> start ();
15. }

* This source code was highlighted with Source Code Highlighter .

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The setDuration (int) method sets the duration of the animation, and the setEasingCurve method (const QEasingCurve &) sets the value change curve over time. In this example, the OutQuad curve is selected.


Actually, 6 lines and all.

To animate a value that is not a property, you can inherit QVariantAnimation and override the void updateCurrentValue (const QVariant &) method. In this method it is necessary to describe the logic of what should happen when the value changes.

QVariantAnimation supports the following types: Int, Double, Float, QLine, QLineF, QPoint, QSize, QSizeF, QRect, QRectF. If the type of changeable value does not belong to any of the above, you need to override the interpolation method. Virtual QVariant interpolated (const QVariant & from, const QVariant & to, qreal progress) const

Here is an example of what happened: