How to create Fade in, Fade out effect in Qt

houmingc

Need guidence in qt, how to create special effect where QPushButton fades out and taken over by
QRadioButton in Qt one by one.
Not sure which class can achieve this effect.

@
//Below is the grid with 3 buttons
QGridLayout *gridLayout = new QGridLayout;
QPushButton *b1 = new QPushButton("A");
QPushButton *b2 = new QPushButton("B");
QPushButton *b3 = new QPushButton("C");
QPushButton *b4 = new QPushButton("D");
QPushButton *b5 = new QPushButton("E");
QPushButton *b6 = new QPushButton("F");

// row 0
gridLayout->addWidget(b1,0,0,1,1);
gridLayout->addWidget(b2,0,1,1,1);
gridLayout->addWidget(b3,0,2,1,1);

// row 1
gridLayout->addWidget(b4,1,0,1,1);

// row 2 with 2 column span
gridLayout->addWidget(b5,2,0,1,2);

//row 3 with 3-column span
gridLayout->addWidget(b6,3,0,1,3);

//create a widget
QWidget *w = new QWidget();
w->setLayout(gridLayout);

//Window Title
w->setWindowTitle("Grid Layout 3 x4");
//Display
w->show();

}

@

euchkatzl

Could you explain a bit more what you want to archive ?

On Button Clicked the Button should disappear and at the same place there should then be a radio button ?

houmingc

In QGridlayout, how to replace item A with item B

euchkatzl

Not quit sure if this is what you expect. But i think you could simply use it for your approach.

@class FadeOutButton : public QWidget
{
Q_OBJECT
public:
explicit FadeOutButton(QWidget *parent = 0);
~FadeOutButton();

signals:

private slots:
void onButtonClicked();
void onAnimationFinished();
private :
QPushButton* mButton;
QRadioButton * mRadioButton;
QGraphicsOpacityEffect* mEffect;
};@

@FadeOutButton::FadeOutButton(QWidget *parent) : QWidget(parent)
{

QGridLayout* layout = new QGridLayout(this);
layout->setContentsMargins(0,0,0,0);

mButton = new QPushButton("Button",this);
mRadioButton = new QRadioButton(this);

layout->addWidget(mButton,0,0,1,1);
layout->addWidget(mRadioButton,0,0,1,1);

mEffect = new QGraphicsOpacityEffect(mButton);
mEffect->setOpacity(1.0);
mButton->setGraphicsEffect(mEffect);

mRadioButton->setVisible(false);
connect(mButton,SIGNAL(clicked()),this,SLOT(onButtonClicked()));

}

FadeOutButton::~FadeOutButton()
{

}

void FadeOutButton::onButtonClicked()
{
QPropertyAnimation* animation = new QPropertyAnimation(mEffect,"opacity");
animation->setDuration(500);
animation->setStartValue(1.0);
animation->setEndValue(0.0);
connect(animation,SIGNAL(finished()),this,SLOT(onAnimationFinished()));
animation->start(QAbstractAnimation::DeleteWhenStopped);
}

void FadeOutButton::onAnimationFinished()
{
mButton->setVisible(false);
mRadioButton->setVisible(true);

}@

houmingc

it work :> thanks alot