I have a MainWindow.cpp class with multiple images displayed that emit a clicked() signal. Once clicked on I want to open a widget that's a fixed size inside MainWindow and I want this widget to be able to be dragged around as long as it stays inside the MainWindow class.
I was looking at example code to try and write this widget class, in particular the Qt MainWindow Example. However, once one of the dockwindows are dragged around the display the Operating System specific titlebar (which lets you maximize, minimize, and close the window) gets displayed. I do not want this titlebar to be displayed.
How would I go about creating this class of draggable widgets?
Check setTitleBarWidget
Setting to a void widget will work:
It is not possible to remove a title bar from a dock widget.
However, a similar effect can be achieved by setting a default constructed QWidget
as the title bar widget.
Edit:
By request:
yourDockableWidget->setTitleBarWidget( new QWidget( yourDockableWidget ) );
In the example you are following, you could do it in constructor:
ColorSwatch::ColorSwatch(const QString &colorName, QWidget *parent, Qt::WindowFlags flags)
: QDockWidget(parent, flags)
{
/*...*/
setTitleBarWidget( new QWidget( this ) );
/*...*/
}
Now your widget wont have SO titlebar when undocked;
Related
I have a scrollarea and I'm setting a basic QWidget as its widget, However when I do this I get a toolbar on top of the widget I just set;
This is the slot I use to create the QWidget and set it to the scroll area, this happens during runtime and the qwidget is deleted and recreated repeatedly during runtime.
void SlotCreateDetailsWidget()
{
if (m_DetailsWidget == nullptr)
{
m_DetailsWidget = new DetailsWidget(); // QWidget
m_Ui->DetailsScrollArea->setWidget(m_DetailsWidget);
m_DetailsWidget->show();
}
}
What do I need to do to get rid of this toolbar?
From https://doc.qt.io/qt-5/qwidget.html :
A widget without a parent widget is always an independent window
(top-level widget).
What you see depends on the underlying windowing system but you can customize it up to a certain point with void QWidget::setWindowFlag(Qt::WindowType flag, bool on = true) for example. You can also look at https://doc.qt.io/qt-5/qtwidgets-widgets-windowflags-example.html.
I've made a QT Designer Form called DropDownMenu. Essentially it is just a QWidget with a QVBoxLayout inside of it.
DropDownMenu has a function that pragmatically adds buttons to it.
QPushButton* DropDownMenu::AddButton(
const QString& text)
{
QPushButton* new_button = new QPushButton(text, this);
m_ui->LayoutManager->addWidget(new_button);
return new_button;
}
I then add a QWidget to my MainWindow inside of QT Designer & promote this widget to DropDownMenu. Then I add buttons to this new QWidget using the AddButton function.
The end result looks like this...
I want to make it so the containers scale according to how many buttons or widgets are placed inside of the layout, but they seem to just get squeezed together so that they fit the parents default size.
How can I make it so the parent scales to the size of all it's children?
I am trying to add a QToolBar in a QWidget. But I want its functionality to work as if it was a QMainWindow.
Apparently I can not create QToolBar in a QWidget, and using setAllowedAreas does not work with QWidget : it only works with QMainWindow. Also, my QWidget is in a QMainWindow.
How can I create a QToolBar for my widget?
The allowedAreas property only works when the toolbar is the child of a QMainWindow. You can add the toolbar to a layout, but it won't be movable by the user. You can still relocate it programmatically, however.
To add it to a layout for a fictional class inheriting QWidget:
void SomeWidget::setupWidgetUi()
{
toolLayout = new QBoxLayout(QBoxLayout::TopToBottom, this);
//set margins to zero so the toolbar touches the widget's edges
toolLayout->setContentsMargins(0, 0, 0, 0);
toolbar = new QToolBar;
toolLayout->addWidget(toolbar);
//use a different layout for the contents so it has normal margins
contentsLayout = new ...
toolLayout->addLayout(contentsLayout);
//more initialization here
}
Changing the toolbar's orientation requires the additional step of calling setDirection on the toolbarLayout, e.g.:
toolbar->setOrientation(Qt::Vertical);
toolbarLayout->setDirection(QBoxLayout::LeftToRight);
//the toolbar is now on the left side of the widget, oriented vertically
QToolBar is a widget. That's why, you can add a QToolBar to any other widget by calling addWidget for layout or by setting the QToolBar parent to your widget.
As you can see in documentation of QToolBar setAllowedAreas method:
This property holds areas where the toolbar may be placed.
The default is Qt::AllToolBarAreas.
This property only makes sense if the toolbar is in a QMainWindow.
That's why it is impossible to use setAllowedAreas if toolbar is not in QMainWindow.
As far as I know, the only way to properly use the toolbar is with the QMainWindow.
If you want to use the full functionality of the toolbar, create a mainwindow with the window flag Widget. This way you can add it inside some other widget without having it displayed as a new window:
class MyWidget : QMainWindow
{
public:
MyWidget(QWidget *parent);
//...
void addToolbar(QToolBar *toolbar);
private:
QMainWindow *subMW;
}
MyWidget::MyWidget(QWidget *parent)
QMainWindow(parent)
{
subMW = new QMainWindow(this, Qt::Widget);//this is the important part. You will have a mainwindow inside your mainwindow
setCentralWidget(QWidget *parent);
}
void MyWidget::addToolbar(QToolBar *toolbar)
{
subMW->addToolBar(toolbar);
}
I have two widgets (both QFrames), none of them have any title bar associated with them (which I achieve through setWindowFlags(Qt::FramelessWindowHint)). One of them is a main widget, and the other a sidebar sort of widget, which is supposed to stick to it at its right boundary (its height being approximately 1/4th of the main widget).
I cannot keep them both in a transparent QFrame with static positioning, since the main widget is draggable through its top (since title bar is missing on it, I do it manually by intercepting mousepress/mousemove events and moving it accordingly). The custom drag on the main widget works fine, but when I try to move the sidebar along with, a very obvious visual delay shows up between the two, there are momentary gaps visible between the two while dragging the main widget to the left, or momentary overlapping between the two when dragging the main widget to the right (the sidebar is not draggable, no drag logic is implemented for it).
How do I 'glue' these two widgets together, such that they move together all the time without any delay? I browsed the Qt docs, it may be possible that QDockWidget can help here, but I could not understand how. The main widget here is not a QMainWindow.
Platform - OS X Yosemite, Qt 5.3.1, 32 bit.
You should definitely use QDockWidget here.
Make your "main widget" derive from QMainWindow rather than QFrame (it may not be "obvious" as QMainWindow does not derive from QFrame, but it should not be such a big deal).
Then, encapsulate your second widget within a QDockWidget and dock it in the main widget like that:
// secondWidget being your QFrame based widget
// mainWidget being your "main widget"
QDockWidget* dockingBar = new QDockWidget("My bar", mainWidget );
dockingBar->setWidget( secondWidget );
// dock on left side, change first parameter to dock somewhere else:
mainWidget->addDockWidget( Qt::LeftDockWidgetArea, dockingBar );
An alternative is to create a third widget that would become your top-level widget and use a QLayout to insert your two QFrames in this new one:
QWidget* newTopLevelWidget = new QWidget();
// QHBoxLayout to have mainWidget on the left hand side of secondWidget
// Replace by QVBoxLayout to have mainWidget on top of secondWidget
QLayout* layout = new QHBoxLayout( newTopLevelWidget );
layout->addWidget( mainWidget );
layout->addWidget( secondWidget );
In a standalone GUI application where I don't have a windowmanager nor a composite manager I want to display a QDialog to the user to ask for values.
The dialog is quite big, so I want to make it translucent so that the user can look through it to see what happens in the application while the dialog is shown.
The problem is that for translucency of X native windows, there needs to be a composite manager. Qt internal widgets can be painted translucent because they don't correspond to native X windows (aliens) and are completely only known to Qt.
Is there a way to make the background of a QDialog translucent without having a composite manager running? Perhaps making it a normal child widget/alien of the application's main window? Is there a better alternative to this?
I don't know of any way of turning a QDialog into a normal child widget. Looking at the Qt for X11 code, I can't figure out a way of not setting the Qt::WindowFlags passed to the QWidget (parent) constructor so that it would be a plain widget and not a window of its own (but I could be wrong, didn't spend a lot of time on that).
A simple alternative is to use a plain QWidget as your container, instead of a QDialog. Here's a sample "PopupWidget" that paints a half-transparent-red background.
#include <QtGui>
class PopupWidget: public QWidget
{
Q_OBJECT
public:
PopupWidget(QWidget *parent): QWidget(parent)
{
QVBoxLayout *vl = new QVBoxLayout;
QPushButton *pb = new QPushButton("on top!", this);
vl->addWidget(pb);
connect(pb, SIGNAL(clicked()), this, SLOT(hide()));
}
public slots:
void popup() {
setGeometry(0, 0, parentWidget()->width(), parentWidget()->height());
raise();
show();
}
protected:
void paintEvent(QPaintEvent *)
{
QPainter p(this);
QBrush b(QColor(255,0,0,128));
p.fillRect(0, 0, width(), height(), b);
}
};
To show it, call it's popup() slot which will raise it to the top of the widget stack, make it as large as its parent, and show it. This will mask all the widgets behind it (you can't interact with them with the mouse). It hides itself when you click on that button.
Caveats:
this doesn't prevent the user from using Tab to reach the widgets underneath. This could be fixed by toggling the enabled property on your "normal" widget container for example. (But don't disable the PopupWidget's parent: that would disable the popup widget itself.)
this doesn't allow for a blocking call like QDialog::exec
the widgets in that popup won't be transparent, you'd have to create custom transparent-background versions for all the widget types you need AFAIK.
But that's probably less of a hassel than integarting a compositing manager in your environment.