Problem with window animation on emulator

[anujgupta131]

Hi,

I am using S60 5th edition and Qt 4.6.0 for my project. I am trying to animate a window launch like the way it appears on iPhone. The animation seems to work fine on desktop but it is not smooth on device(N97) and emulator. It leaves trails of previous frames that are painted.

Here is the code

//MyWidget inherits from QWidget, it contains a QWebView, QLabel and QPushButton arranged in
// QVBoxLayout
MYWidget::MYWidget(QWidget *parent)
{
//code to layout text edit and buttons

QPropertyAnimation *animation = new QPropertyAnimation( this, "geometry");
animation->setDuration(600);
animation->setKeyValueAt(0, QRect ( 320 ,180 , 20 ,20));
animation->setKeyValueAt(1, QRect( 10, 10, 620, 340));
animation->start();
connect(animation, SIGNAL(valueChanged(QVariant)), this, SLOT(update));
}

void MYWidget:aintEvent(QPaintEvent *pnt)
{
//code to draw the border using QPainter
QPainter painter(this);
QColor current_color = Qt::black;
QPen pen;
pen.setWidth(borderPenWidth);
current_color.setAlpha(100);
pen.setColor(current_color);
painter.setPen(pen);
painter.drawRoundedRect(QRectF(10, 10, 620 , 340, 5.0, 5.0);
}

i have also tried using QTimeLine to animate it. But it also has the same problem. The grow effect is not smooth and it leaves trails of previous frames.

How can i get it smooth like it is on iPhone. I have seen a video on Qt Developer Days which had the same effect i wanted but i don't know how they did it.

Any pointers on how to achieve the application\window launch effect similar to iPhone will be of great help.

Thanks,
Anuj

[rahulvala]

Hi,

I am using S60 5th edition and Qt 4.6.0 for my project. I am trying to animate a window launch like the way it appears on iPhone. The animation seems to work fine on desktop but it is not smooth on device(N97) and emulator. It leaves trails of previous frames that are painted.

Here is the code

//MyWidget inherits from QWidget, it contains a QWebView, QLabel and QPushButton arranged in
// QVBoxLayout
MYWidget::MYWidget(QWidget *parent)
{
//code to layout text edit and buttons

QPropertyAnimation *animation = new QPropertyAnimation( this, "geometry");
animation->setDuration(600);
animation->setKeyValueAt(0, QRect ( 320 ,180 , 20 ,20));
animation->setKeyValueAt(1, QRect( 10, 10, 620, 340));
animation->start();
connect(animation, SIGNAL(valueChanged(QVariant)), this, SLOT(update));
}

void MYWidget:aintEvent(QPaintEvent *pnt)
{
//code to draw the border using QPainter
QPainter painter(this);
QColor current_color = Qt::black;
QPen pen;
pen.setWidth(borderPenWidth);
current_color.setAlpha(100);
pen.setColor(current_color);
painter.setPen(pen);
painter.drawRoundedRect(QRectF(10, 10, 620 , 340, 5.0, 5.0);
}

i have also tried using QTimeLine to animate it. But it also has the same problem. The grow effect is not smooth and it leaves trails of previous frames.

How can i get it smooth like it is on iPhone. I have seen a video on Qt Developer Days which had the same effect i wanted but i don't know how they did it.

Any pointers on how to achieve the application\window launch effect similar to iPhone will be of great help.

Thanks,
Anuj

It is ordinary that it is going to make back image..

This is due to the slow grow effect .

Try to make faster the grow effect , it will definitely reduce the flickering or back image production...

Best regards,

[divanov]

How can i get it smooth like it is on iPhone. I have seen a video on Qt Developer Days which had the same effect i wanted but i don't know how they did it.

That demo was probably implemented with OpenGL ES.