C++ 如何设置机器动画持续时间

我正在努力学习Qt框架。我的QStateMachine代码做了正确的事情按下按钮使聊天窗口弹出窗口改变大小。 我不能改变动画的速度来获得一个好的视觉过渡。 有什么建议吗

代码如下：

MainWindow::MainWindow()
{
   widget.setupUi( this );

   // chat window - Chat button opens
   ChatWindowClosedState = new QState();
   ChatWindowOpenState = new QState();

   ChatWindowOpenGeometry = widget.groupBox->geometry();
   ChatWindowClosedGeometry = widget.pushButton->geometry();
   ChatWindowClosedGeometry.translate( -ChatWindowClosedGeometry.width(), 0 );

   ChatWindowClosedState->assignProperty( widget.groupBox, "geometry", ChatWindowClosedGeometry );
   ChatWindowOpenState->assignProperty( widget.groupBox, "geometry", ChatWindowOpenGeometry );

   ChatWindowCloseTransition = ChatWindowClosedState->addTransition( widget.pushButton, SIGNAL( clicked() ), ChatWindowOpenState );
   ChatWindowCloseAnimation = new QPropertyAnimation( widget.pushButton, "geometry" );
   ChatWindowCloseAnimation->setDuration( 5000 );
   ChatWindowCloseTransition->addAnimation( ChatWindowCloseAnimation );

   ChatWindowOpenTransition = ChatWindowOpenState->addTransition( widget.pushButton, SIGNAL( clicked() ), ChatWindowClosedState );
   ChatWindowOpenAnimation = new QPropertyAnimation( widget.pushButton, "geometry" );
   ChatWindowOpenAnimation->setDuration( 5000 );
   ChatWindowOpenTransition->addAnimation( ChatWindowOpenAnimation );

   machine = new QStateMachine( this );
   machine->addState( ChatWindowClosedState );
   machine->addState( ChatWindowOpenState );
   machine->setInitialState( ChatWindowClosedState );
   machine->start();
}

代码

ChatWindowOpenAnimation = new QPropertyAnimation( widget.pushButton, "geometry" );

应该是

ChatWindowOpenAnimation = new QPropertyAnimation( widget.groupBox, "geometry" );

动画应用于错误的小部件