How to animate a QSplitter?

Kattia

Given the following example built-in Qt Designer:

The GUI is started with the space occupied by frame hidden:

    QList<int> list = { 0, 400 };
    ui.splitter->setSizes(list);
    ui.frame->setWindowOpacity(0);

How can I animate the frame while bringing her occupied space back?

I tried animating it as:

// splitteranimation.h

void SplitterAnimation(QWidget* widget)
{
    int ani_speed = 1000;

    QPropertyAnimation* geo_ani = new QPropertyAnimation(widget, "geometry");
    geo_ani->setDuration(ani_speed);
    geo_ani->setStartValue(widget->rect());

    QRect end = QRect(widget->rect().x(), widget->rect().y(), widget->rect().width() + 200, widget->rect().height());
    geo_ani->setEndValue(end);



    QGraphicsOpacityEffect *eff = new QGraphicsOpacityEffect();
    widget->setGraphicsEffect(eff);
    QPropertyAnimation *op_eff = new QPropertyAnimation(eff, "opacity");
    op_eff->setDuration(ani_speed);
    op_eff->setStartValue(0);
    op_eff->setEndValue(1);



    auto animgroup = new QParallelAnimationGroup;
    animgroup->addAnimation(geo_ani);
    animgroup->addAnimation(op_eff);
    animgroup->start(QAbstractAnimation::DeleteWhenStopped);
}

#include "splitteranimation.h"


MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
{
    ui.setupUi(this);

    QList<int> list = { 0, 400 };
    ui.splitter->setSizes(list);
    ui.frame->setWindowOpacity(0);

    QShortcut *shortcut = new QShortcut(QKeySequence(Qt::Key_F2), this);
    connect(shortcut, &QShortcut::activated, [=]
    {
        qDebug() << "shortcut!";
	    SplitterAnimation(ui.frame);

    });

    shortcut = new QShortcut(QKeySequence(Qt::Key_F3), this);
    connect(shortcut, &QShortcut::activated, [this]
    {
        qDebug() << "shortcut!";
	    SplitterAnimation(ui.splitter);
    });
}

When I call the geometry animation in the frame (F2), the frame get resized but the space occupied by it continue 'hidden', the splitter areas didn't get resized:

When i call the animation directly in the splitter (F3), the frame didn't get resized/ visible.

SGaist

Hi and welcome to devnet,

From the top of my head, I would rather animate the handle than the widget that is in the splitter.