I'm having trouble getting my QtGraphicsView to take up 100% of the window I'm working in. Is there a way to set the view size to take up 100% of the graphics window that is created?
QApplication app(argc, argv);
QGraphicsScene * scene = new QGraphicsScene();
int counter = 1000;
scene->setSceneRect(0, 0, counter, counter);//scene size
QGraphicsEllipseItem * item = new QGraphicsEllipseItem(0, scene);
item->setRect(0,0, 1000.0, 1000.0);
QGraphicsView view(scene);
view.setRect(100, 100);
view.setRenderHints(QPainter::Antialiasing);
view.show();
QGraphicsView should have a method(slot) called showFullScreen since it inherits QWidget
, which should do what you want.
Related
I have class named Pixmap deriving from QGraphicsPixmapItem and StartScreen class deriving from QGraphicsScene. I want to use animations (QPropertyAnimation class) to resize displayed image in certain time range. Other actions like setting position or rotation aren't problem but I couldn't find any property like size (e.g. setSize() method). How can I do that in the other way? Thanks for advance.
StartScreen::StartScreen(int windowWidth, int windowHeight)
{
setSceneRect(0, 0, windowWidth, windowHeight);
setBackgroundBrush(QBrush(QImage(":/images/background.png")));
Pixmap * logo = new Pixmap(":/images/logo.png");
addItem(logo);
logo->setPos((windowWidth - logo->pixmap().width()) / 2, (windowWidth - logo->pixmap().width()) / 2 - 75);
//QPropertyAnimation * animation = new QPropertyAnimation(logo, "");
}
QPropertyAnimation applies to Qt Properties, but only objects that inherit from QObject have Qt properties, so if you want to use animations you can use QGraphicsObject and create your own item, or create a class that inherits the item you want and QObject.
class Pixmap: public QObject, public QGraphicsPixmapItem{
Q_OBJECT
Q_PROPERTY(qreal scale READ scale WRITE setScale)
Q_PROPERTY(qreal rotation READ rotation WRITE setRotation)
Q_PROPERTY(QPointF pos READ pos WRITE setPos)
public:
using QGraphicsPixmapItem::QGraphicsPixmapItem;
};
In the previous example, take advantage of the fact that QGraphicsItem, and therefore its derived classes, have the methods pos(), setPos(), scale(), setScale(), rotation() and setRotation(), so only use them in Q_PROPERTY.
In the next part I show an example:
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QGraphicsView w;
QGraphicsScene scene(0, 0, 640, 480);
w.setScene(&scene);
w.show();
Pixmap* logo = new Pixmap(QPixmap(":/image.jpg"));
scene.addItem(logo);
QSequentialAnimationGroup group;
QPropertyAnimation animation_scale(logo, "scale");
animation_scale.setDuration(1000);
animation_scale.setStartValue(2.0);
animation_scale.setEndValue(0.1);
QPropertyAnimation animation_pos(logo, "pos");
animation_pos.setDuration(1000);
animation_pos.setStartValue(QPointF(0, 0));
animation_pos.setEndValue(QPointF(100, 100));
/**
* it must indicate the center of rotation,
* in this case it will be the center of the item
*/
logo->setTransformOriginPoint(logo->boundingRect().center());
QPropertyAnimation animation_rotate(logo, "rotation");
animation_rotate.setDuration(1000);
animation_rotate.setStartValue(0);
animation_rotate.setEndValue(360);
group.addAnimation(&animation_scale);
group.addAnimation(&animation_pos);
group.addAnimation(&animation_rotate);
group.start();
return a.exec();
}
#include "main.moc"
In the following link there is an example
Or you can use QVariantAnimation instead of QPropertyAnimation:
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QGraphicsView w;
QGraphicsScene scene(0, 0, 640, 480);
w.setScene(&scene);
w.show();
QGraphicsPixmapItem* logo = new QGraphicsPixmapItem(QPixmap(":/image.jpg"));
scene.addItem(logo);
QSequentialAnimationGroup group;
QVariantAnimation animation_scale;
animation_scale.setDuration(1000);
animation_scale.setStartValue(2.0);
animation_scale.setEndValue(0.5);
QObject::connect(&animation_scale, &QVariantAnimation::valueChanged, [logo](const QVariant &value){
logo->setScale(value.toReal());
});
animation_scale.start();
QVariantAnimation animation_pos;
animation_pos.setDuration(1000);
animation_pos.setStartValue(QPointF(0, 0));
animation_pos.setEndValue(QPointF(100, 100));
QObject::connect(&animation_pos, &QVariantAnimation::valueChanged, [logo](const QVariant &value){
logo->setPos(value.toPointF());
});
/**
* it must indicate the center of rotation,
* in this case it will be the center of the item
*/
logo->setTransformOriginPoint(logo->boundingRect().center());
QVariantAnimation animation_rotate;
animation_rotate.setDuration(1000);
animation_rotate.setStartValue(0);
animation_rotate.setEndValue(360);
QObject::connect(&animation_rotate, &QVariantAnimation::valueChanged, [logo](const QVariant &value){
logo->setRotation(value.toReal());
});
group.addAnimation(&animation_scale);
group.addAnimation(&animation_pos);
group.addAnimation(&animation_rotate);
group.start();
return a.exec();
}
In the following link there is an example
I have more than one widget in QGraphicsScene. The first created widget is on top of scene, other widgets is under first widget. I want such functionality - if i press one of widget it will be on top of the scene. How i can make it?
Also i don't know, how to make border to the widget in QGraphicsScene like the normal widget. This is the code:
QGraphicsScene *scene ;
QGraphicsProxyWidget *pw()
{
QWidget *w = new QWidget;
w->resize(580, 280);
w->setStyleSheet("background-color: rgb(110, 149, 255)");
QPushButton *p = new QPushButton;
p->setParent(w);
p->move(30, 50);
p->setText("hello");
QPushButton *p2 = new QPushButton;
p2->setParent(w);
p2->move(110, 50);
p2->setText("world");
QGraphicsWidget *parentWidget = new QGraphicsWidget();
parentWidget->setMinimumSize(QSizeF(100, 30));
parentWidget->setFlags(QGraphicsItem::ItemIsMovable);
parentWidget->setAutoFillBackground(true);
parentWidget->resize(580, 280);
scene->addItem(parentWidget);
QGraphicsProxyWidget *proxyWidget = new QGraphicsProxyWidget;
proxyWidget->setWidget(w);
proxyWidget->setParentItem(parentWidget);
return proxyWidget;
}
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
scene = new QGraphicsScene;
scene->setSceneRect(0, 0, 800, 480);
scene->addItem(pw());
scene->addItem(pw());
scene->addItem(pw());
scene->setBackgroundBrush(Qt::darkGreen);
QGraphicsView view(scene);
view.show();
return a.exec();
}
Currently I have a QGraphicsScene that is put inside a QGraphicsView and is shown on the display. I add all my elements to my scene that I set as the active scene.
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QGraphicsView w;
GameScene *gameScene = new GameScene(); // GameScene extends QGraphicsScene, adds tons of elements to the scene
w.setScene(gameScene);
w.show();
return a.exec();
}
Above this scene I want a bar that contains several layout elements, like several QProgressBar.
For what I have found so far, QWidget's can be positioned easily. I've made already a widget of what I need to be displayed above the scene:
QWidget *dummyWidget = new QWidget();
QFormLayout *formLayout = new QFormLayout;
QProgressBar *bar1 = new QProgressBar();
QProgressBar *bar2 = new QProgressBar();
bar1->setValue(20);
bar2->setValue(100);
formLayout->addRow("&Health:", bar1);
formLayout->addRow("&Energy:", bar2);
dummyWidget->setLayout(formLayout);
dummyWidget->show();
But how do I get this to be displayed above my QGraphicsScene?
If you want to display your widget above the view you can have a layout similar to the one for dummyWidget and add the widget and view in it :
QGraphicsView w;
QWidget *widget = new QWidget();
QFormLayout *formLayout2 = new QFormLayout(widget);
QWidget *dummyWidget = new QWidget();
QFormLayout *formLayout = new QFormLayout;
QProgressBar *bar1 = new QProgressBar();
QProgressBar *bar2 = new QProgressBar();
bar1->setValue(20);
bar2->setValue(100);
formLayout->addRow("&Health:", bar1);
formLayout->addRow("&Energy:", bar2);
dummyWidget->setLayout(formLayout);
formLayout2->addRow("", dynamic_cast<QWidget*>(dummyWidget));
formLayout2->addRow("", dynamic_cast<QWidget*>(&w));
widget->show();
If you want to add the widget in the scene, you can use QGraphicsScene::addWidget which creates a new QGraphicsProxyWidget for widget, adds it to the scene, and returns a pointer to the proxy :
QGraphicsProxyWidget * item = gameScene->addWidget(dummyWidget);
item->setPos(100,100);
item->setZValue(1);
You can also add it to an item :
item->setParentItem(anOtherItem);
I am using QPainter on QPixmap as the painting framework. And QGraphicsScene is holding the QPixmap. The painting works well. But the problem is when I change the the background-color of the QGraphicsView it does not get reflected on the screen. I tried by QPixmap::fill(Qt::tranparent). But it didnt work.
How can I achieve this kind of transparent QPixmap?
Thanx in advance?
int main(int argc, char **argv){
QApplication a(argc, argv);
QMainWindow *win = new QMainWindow();
win->resize(600,600);
win->move(80,80);
win->show();
QGraphicsScene *scene = new QGraphicsScene(win);
QGraphicsView view(scene,win);
view.resize(590,590);
view.setBackgroundBrush(QColor(rand()%255,rand()%255, rand()%255, 255));
view.show();
QPixmap *pix = new QPixmap(600,600);
pix->fill(&view,QPoint(0,0));
QGraphicsPixmapItem *item = scene->addPixmap(*pix);
QPainter *painter = new QPainter(pix);
int count=10;
while(count){
painter->setPen((*new QColor(rand()%255,rand()%255, rand()%255, 255)));
painter->setBrush(QColor(rand()%255,rand()%255, rand()%255, 255));
painter->drawRect(rand()%300, rand()%300, rand()%300, rand()%300);
item->setPixmap(*pix);
a.processEvents(0x00);
count--;
}
return a.exec();
}
I am having trouble getting a QGraphicsView to show up in a QVBoxLayout object and I have no idea what is wrong. My code compiles so no errors are being thrown. Here is my simple code. (I am a Qt and C++ newb). At the bottom, I add a QPushButton widget to the layout and that shows up fine. Thanks for your help in advance!
QGraphicsScene scene;
QGraphicsView view(&scene);
view.setBackgroundBrush(QImage(":/images/bg/tile.png"));
view.setCacheMode(QGraphicsView::CacheBackground);
QPixmap pixmap("images/icons/dsp.gif");
QGraphicsPixmapItem* dsp = scene.addPixmap(pixmap);
view.show();
vlayout->addWidget(&view);
vlayout->addWidget(new QPushButton("some button here"));
Not enough context, so I can't tell what's happening exactly. But, if those are in a function, then you are declaring local variables that are gone once the function exits. If you are in the main, you're code should look something like this, but it will probably crash:
QApplication app(argc, argv);
QGraphicsScene scene;
QGraphicsView view(&scene);
QWidget widget;
view.setBackgroundBrush(Qt::red);
QVBoxLayout vlayout;
widget.setLayout(&vlayout);
vlayout.addWidget(&view);
vlayout.addWidget(new QPushButton("some button here"));
widget.show();
I recommend dynamically allocating objects:
int main(int argc, char* argv[]){
QApplication app(argc, argv);
QGraphicsScene* scene = new QGraphicsScene;
QGraphicsView* view = new QGraphicsView(scene);
QWidget *widget = new QWidget;
view->setBackgroundBrush(Qt::red);
QVBoxLayout* vlayout = new QVBoxLayout(widget);
vlayout->addWidget(view);
vlayout->addWidget(new QPushButton("some button here"));
widget->show();
return app.exec();
}
Don't forget to delete the parent object so it doesn't leak memory.