Animate an hidden widget

[AlbertoN]

Hi all,

I'd like to animate (show and hide) a widget when a toggle button is pressed.
I wrote this code:

MainWindow::MainWindow
{
   [...]
    //ui->widget->hide();//[1]
    //ui->button->setChecked(false);//[2]
   startgeometry = QRect(0,0,0,0);
   connect(ui->button,SIGNAL(toggled(bool)),this,SLOT(togglePyShell(bool)));
}
 
void MainWindow::togglePyShell(bool show)
{
    QRect formerGeometry = QRect(ui->widget->geometry());
    if(startgeometry==QRect(0,0,0,0)){
        startgeometry = formerGeometry;
    }
    if(show){
        //ui->widget->show();//[3]
        QPropertyAnimation *showAnimation = new QPropertyAnimation(ui->widget, "geometry");
        showAnimation->setDuration(100); 
        showAnimation->setEasingCurve(QEasingCurve::Linear);
        showAnimation->setStartValue(formerGeometry);
        showAnimation->setEndValue(startgeometry);
        showAnimation->start(QPropertyAnimation::DeleteWhenStopped);
    }else{
        QPropertyAnimation *hideAnimation = new QPropertyAnimation(ui->widget, "geometry");
        hideAnimation->setDuration(100); 
        hideAnimation->setEasingCurve(QEasingCurve::Linear);
        hideAnimation->setStartValue(formerGeometry);
        QPoint endTopLeftCorner = QPoint(ui->widget->pos() + QPoint(0, ui->widget->height()));
        QRect finalGeometry = QRect(endTopLeftCorner, QSize(ui->widget->width(), 0));
        hideAnimation->setEndValue(finalGeometry);
        hideAnimation->start(QPropertyAnimation::DeleteWhenStopped);
        //ui->widget->hide();//[4]
    }
}

MainWindow::MainWindow
{
   [...]
    //ui->widget->hide();//[1]
    //ui->button->setChecked(false);//[2]
   startgeometry = QRect(0,0,0,0);
   connect(ui->button,SIGNAL(toggled(bool)),this,SLOT(togglePyShell(bool)));
}

void MainWindow::togglePyShell(bool show)
{
    QRect formerGeometry = QRect(ui->widget->geometry());
    if(startgeometry==QRect(0,0,0,0)){
        startgeometry = formerGeometry;
    }
    if(show){
        //ui->widget->show();//[3]
        QPropertyAnimation *showAnimation = new QPropertyAnimation(ui->widget, "geometry");
        showAnimation->setDuration(100); 
        showAnimation->setEasingCurve(QEasingCurve::Linear);
        showAnimation->setStartValue(formerGeometry);
        showAnimation->setEndValue(startgeometry);
        showAnimation->start(QPropertyAnimation::DeleteWhenStopped);
    }else{
        QPropertyAnimation *hideAnimation = new QPropertyAnimation(ui->widget, "geometry");
        hideAnimation->setDuration(100); 
        hideAnimation->setEasingCurve(QEasingCurve::Linear);
        hideAnimation->setStartValue(formerGeometry);
        QPoint endTopLeftCorner = QPoint(ui->widget->pos() + QPoint(0, ui->widget->height()));
        QRect finalGeometry = QRect(endTopLeftCorner, QSize(ui->widget->width(), 0));
        hideAnimation->setEndValue(finalGeometry);
        hideAnimation->start(QPropertyAnimation::DeleteWhenStopped);
        //ui->widget->hide();//[4]
    }
}

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It works if the widget is visible after costructor (and button pressed), but I'd like to start with the widget invisible (and button not checked).

I don't know how to hide the widget.
If i try to uncomment from [1] up to [4] or subset of them I have strange behaviour, because (i guess) I can't save original widget's size into startgeometry.

Any help is appreciated,
Thanks in advance.

[anda_skoa]

If you don't have a start geometry and you show, wouldn't the animation go from "0,0,0,0" to "current geometry"?

Cheers,
_

[AlbertoN]

Maybe i didn't understand your reply.

But if i remove startgeometry QRect and I show the widget I wouldn't have what I want: start with a hidden widget.

On the other hand if I hide the widget (ui->widget->hide() ) how can I get final widget's geometry of widget (for "show transition")?

[AlbertoN]

Thanks to anda_skoa I solved in this way, maybe it could be useful for someone else.

void MainWindow::resizeEvent(QResizeEvent *)
{
    //in case of window resize we have to hide widget so we'll fall in first case(see below) and set push button as unchecked
    if(ui->widget->isVisible()){
        ui->widget->setHidden(true);
        ui->button->setChecked(false);
    }
}
 
void MainWindow::showWidget()
{
    QRect fo;
    QRect fi;
 
    //There are 2 cases:
    //   1. Widget was never shown before,
    //   2.Widget was shown (at least) once and then hide again,
    if(ui->widget->isHidden()){
        //If the widget is hidden then we're in the first case.
 
        //We set up y coord of starting transition to a bigger value than height coord and all other
        //coords at the widget's coords; while we have to set up final transition coords to widget's coords.
        //In this way it'll look like upward motion.
 
 
        //PLEASE NOTE: before you have to perform ui->widget->show() and then get widget's size() and pos(), else you'll get wrong values.
 
        ui->widget->show();
        QPoint pos = ui->widget->pos();
        QSize size = ui->widget->size();
 
        fo = QRect(pos.x(),pos.y()+size.height(),size.width(),size.height());
        fi = QRect(pos,size);
    }else{
        //in second case: we have to set up start transition coords at actual coords of widget, as it's hidden 
        //we would have y = y + height, and we set up y coord of final transition coords to y = y - height.
        fo = ui->widget->geometry();
        fi = QRect(fo.x(),fo.y()-fo.height(),fo.width(),fo.height());
    }
    QPropertyAnimation *showAnimation = new QPropertyAnimation(ui->widget, "geometry");
    showAnimation->setDuration(100);
    showAnimation->setEasingCurve(QEasingCurve::Linear);
    showAnimation->setStartValue(fo);
    showAnimation->setEndValue(fi);
    showAnimation->start(QPropertyAnimation::DeleteWhenStopped);
}
 
void MainWindow::hideWidget()
{
    //coords of starting transition must be set up at actual widget's coords, as it's visible; while final 
    //transition coords must be set up with: y = y + height.
 
    QRect fo = QRect(ui->widget->geometry());
    QRect fi = QRect(fo.x(),fo.y()+fo.height(),fo.width(),fo.height());
 
    QPropertyAnimation *hideAnimation = new QPropertyAnimation(ui->widget, "geometry");
    hideAnimation->setDuration(100);
    hideAnimation->setEasingCurve(QEasingCurve::Linear);
 
    hideAnimation->setStartValue(fo);
    hideAnimation->setEndValue(fi);
    hideAnimation->start(QPropertyAnimation::DeleteWhenStopped);
}
 
void MainWindow::togglePyShell(bool show)
{
    if(show){
        showWidget();
    }else{
        hideWidget();
    }
}

void MainWindow::resizeEvent(QResizeEvent *)
{
    //in case of window resize we have to hide widget so we'll fall in first case(see below) and set push button as unchecked
    if(ui->widget->isVisible()){
        ui->widget->setHidden(true);
        ui->button->setChecked(false);
    }
}

void MainWindow::showWidget()
{
    QRect fo;
    QRect fi;

    //There are 2 cases:
    //   1. Widget was never shown before,
    //   2.Widget was shown (at least) once and then hide again,
    if(ui->widget->isHidden()){
        //If the widget is hidden then we're in the first case.

        //We set up y coord of starting transition to a bigger value than height coord and all other
        //coords at the widget's coords; while we have to set up final transition coords to widget's coords.
        //In this way it'll look like upward motion.


        //PLEASE NOTE: before you have to perform ui->widget->show() and then get widget's size() and pos(), else you'll get wrong values.

        ui->widget->show();
        QPoint pos = ui->widget->pos();
        QSize size = ui->widget->size();

        fo = QRect(pos.x(),pos.y()+size.height(),size.width(),size.height());
        fi = QRect(pos,size);
    }else{
        //in second case: we have to set up start transition coords at actual coords of widget, as it's hidden 
        //we would have y = y + height, and we set up y coord of final transition coords to y = y - height.
        fo = ui->widget->geometry();
        fi = QRect(fo.x(),fo.y()-fo.height(),fo.width(),fo.height());
    }
    QPropertyAnimation *showAnimation = new QPropertyAnimation(ui->widget, "geometry");
    showAnimation->setDuration(100);
    showAnimation->setEasingCurve(QEasingCurve::Linear);
    showAnimation->setStartValue(fo);
    showAnimation->setEndValue(fi);
    showAnimation->start(QPropertyAnimation::DeleteWhenStopped);
}

void MainWindow::hideWidget()
{
    //coords of starting transition must be set up at actual widget's coords, as it's visible; while final 
    //transition coords must be set up with: y = y + height.

    QRect fo = QRect(ui->widget->geometry());
    QRect fi = QRect(fo.x(),fo.y()+fo.height(),fo.width(),fo.height());

    QPropertyAnimation *hideAnimation = new QPropertyAnimation(ui->widget, "geometry");
    hideAnimation->setDuration(100);
    hideAnimation->setEasingCurve(QEasingCurve::Linear);

    hideAnimation->setStartValue(fo);
    hideAnimation->setEndValue(fi);
    hideAnimation->start(QPropertyAnimation::DeleteWhenStopped);
}

void MainWindow::togglePyShell(bool show)
{
    if(show){
        showWidget();
    }else{
        hideWidget();
    }
}

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