I'm using a custom QGraphicsWidget and when I right click on it I want to bring up a menu. I'm starting it like this:
void myQGraphicsWidget::mousePressEvent(QGraphicsSceneMouseEvent *event){
if(event->button() & Qt::RightButton){
const QString test = "test";
QMenu menu;
menu.setTitle(test);
menu.addAction(test);
menu.exec(mapToScene(event->pos()).toPoint());
//menu.exec(mapToScene(QPointF(0,0)).toPoint());
}
}
but the menu shows up way outside of the main application window towards the bottom right of my other monitor. When I use the commented out version then it appears resting on top of my main window. I've tried adjusting the point manually to massage it inside the window but it will just jump to either resting on top of the window or hanging from the bottom, never inside.
QMenu::exec takes a global position; you're taking the widget-relative position and mapping it to the scene position.
Try this instead:
menu.exec(event->screenPos());
Related
I wirte a codeEdit based on plainEdit, and I need to move to specified line. The below code relize the function patially. The proplem is that the cursor is on the bottom of the widget. Is there some way to put the cursor (yellow line) in the middle of the widget.
void MainWindow::run(){
QTextCursor text_cursor(SPUEdit->document()->findBlockByNumber(100));
SPUEdit->setTextCursor(text_cursor);
// SPUEdit->verticalScrollBar()->setValue(12);
}
You should call centerCursor method of QPlainTextEdit:
void QPlainTextEdit::centerCursor()
Scrolls the document in order to
center the cursor vertically.
I put a push button into the top-right corner of my main window menu bar:
QPushButton *pb = new QPushButton("Text");
pb->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Preferred);
QMainWindow *mainWindow;
mainWindow->menuBar()->setCornerWidget(pb, Qt::TopRightCorner);
The initial layout is fine. Sometime later, an asynchronous event changes the QPushButton's text to a longer string, but it gets clipped on the right.
I can see that the QPushButton's size changes when the string is updated. The QPushButton is displayed correctly if the window is resized. The problem appears to be getting the QMenuBar to recognize that the widget's size has changed.
This answer How to auto change QPushButton width and QMenuBar corner widget width when change text of button? suggests resetting the corner widget. I would rather avoid that, because my application's structure makes me jump through several ugly and awkward hoops to reset the corner widget after initializing.
The solution is simple. After updating the text of the button call menuBar()->adjustSize(); I have tested it in Qt5.5 and hope it will work for you.
You can use QWidgetAction as a horizontal menu widget:
class TestMenu : public QWidgetAction
{
public:
TestMenu(QObject *parent) :
QWidgetAction (parent)
{
}
virtual QWidget *createWidget(QWidget *parent)
{
QComboBox *combo = new QComboBox(parent);
combo->setFixedWidth(300);
return combo;
}
virtual void deleteWidget(QWidget *widget)
{
delete widget;
}
};
...
QMenu *menu = new QMenu();
menu->addAction(new TestMenu(this));
menuBar()->setCornerWidget(menu);
Making my way up the Qt learning curve, I've seen many questions about dynamic layouts but the solutions aren't working for me or I don't quite understand them.
Reference questions:: Qt Scroll Area does not add in scroll bars, How can i make widgets overflow to make a scrollbar appear in Qt?
Question:: I want to have a dynamic layout of a set of widgets within a QScrollArea. I've been able to do this manually in Qt Creator and now I am trying to do it through code.
How do I prevent the widgets from stretching/force the area to scroll?
How do I have the added widgets start from the top? I have a vertical spacer in my QVBoxLayout but that pushes everything to the bottom.
Simple test code::
void MainWindow::on_pushButton_clicked()
{
ui->myScroll->setWidgetResizable(true); //making sure this is set
QPushButton *b = new QPushButton(this);
b->setText(QString("Hello Button"));
QHBoxLayout *h = new QHBoxLayout();
h->addWidget(b,0);
ui->myVBoxLayout->addLayout(h,0);
}
Result:: Left side squished (dynamic) – Right side Ok (set up manually)
Qt Creator Setup:: Left side: dynamic – Right side set up manually
Properties::
You can set use setMinimumHeight() on your buttons for preventing squished buttons. The layout can be configured with setContentsMargin() for space between item-border and item-content (QtDesigner has all four directions set to 9 IIRC) and setSpacing() for space between items (QtDesigner uses a default of 6). Also setWidgetResizable(true) allows your scrollarea to resize the view widgeth inside the area (this is where your layout and children are being placed).
This works for me:
In constructor or code set scrollArea->widget() to hold the QVBoxLayout:
v = new QVBoxLayout;
ui->scrollArea->widget()->setLayout(v);
In Button Slot:
void MainWindow::pushButtonPressed()
{
ui->scrollArea->setWidgetResizable(true);
QPushButton *b = new QPushButton(this);
b->setText(QString("Hello Button"));
QHBoxLayout *h = new QHBoxLayout();
h->addWidget(b,0);
v->addLayout(h);
}
I use Qt and I want to move some object with mouse. For example, user clicks on object and drag this object to another place of window. How I can do it?
I tried mouseMoveEvent:
void QDropLabel::mouseMoveEvent(QMouseEvent *ev)
{
this->move(ev->pos());
}
but unfortunately object moves very strange way. It jumps from place to place.
QDropLabel inherits QLabel. Also it has given a pixmap.
I tried to do it with different objects, but result is same.
Your movable widget must have a QPoint offset member. It will store a position of the cursor click relative to the widget's top left corner:
void DropLabel::mousePressEvent(QMouseEvent *event)
{
offset = event->pos();
}
On mouse move event you just move your widget in its parent coordinate system. Note that if you don't subtract offset from the cursor position, your widget will 'jump' so its top left corner will be just under the cursor.
void DropLabel::mouseMoveEvent(QMouseEvent *event)
{
if(event->buttons() & Qt::LeftButton)
{
this->move(mapToParent(event->pos() - offset));
}
}
I have a modal QDialog, that on the click of a button slides a modeless child QDialog out from underneath it. The problem I have is that the child stays on top of its parent during the animation.
I think I could get away with applying a mask over the portion of the child that overlaps the parent, but it feels like I'm missing a more obvious way of just placing the child under the parent.
I'm using Qt 4.5. Here's some sample code:
void MainWindow::on_myMenu_triggered()
{
parentDlg = new QDialog(this);
parentDlg->setFixedSize(250, 250);
parentDlg->setModal(true);
parentDlg->show();
childDlg = new QDialog(parentDlg);
childDlg->setFixedSize(150, 150);
childDlg->show();
QTimeLine* timeLine = new QTimeLine(1000, this);
connect(timeLine, SIGNAL(valueChanged(qreal)), this, SLOT(childDlgStepChanged(qreal)));
timeLine->start();
}
void MainWindow::childDlgStepChanged(qreal)
{
int parentX = parentDlg->frameGeometry().x();
int parentY = parentDlg->geometry().y();
// Move the child dialog to the left of its parent.
childDlg->move(parentX - 150 * step, parentY);
}
Thanks in advance.
Child widgets are always rendered over the parent so you would have to break that relationship in order to achieve the affect you are looking for directly. Then you could use raise() or lower() if both dialogs had the same parent.