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 );
Related
I designed a QMainWindow with QtCreator's designer. It consists of the default central widget (a QWidget) which contains a QVBoxLayout with all the other widgets in it. Now everything I want, is that the QVBoxLayout automatically occupies the whole central widgets rectangle space.
How can I do this? I didn't find any usable property neither in the central widgets properties nor the QVBoxLayout's ones.
If you want to do it with code instead of using QtCreator, you could set the layout in a QWidget and then set the QWidget as the central widget of the main window like this:
#include <QtGui>
#include <QWidget>
#include <QHBoxLayout>
#include "mainwindow.h"
MainWindow::MainWindow() {
// Set layout
QHBoxLayout *layout = new QHBoxLayout;
layout->addWidget(myWidget1);
layout->addWidget(myWidget2);
// Set layout in QWidget
QWidget *window = new QWidget();
window->setLayout(layout);
// Set QWidget as the central layout of the main window
setCentralWidget(window);
}
You don't have to create a QVBoxLayout manually. Just select your central QWidget and press a make-layout button.
Add at least one widget on your MainWindow. Then select your window by clicking on it and click on the VerticalLayout Button at the top of QTCreator. You Vertical Layout is automatically added to the central widget and fills all the surface.
This is already answered, but I personally prefer to keep all control elements and layouts added manually to the form. I do not add controls in the class files, I merely hook up the signals/slots to hide/show widgets relevant to the logic in the class, within the class.
To manually add a layout to any widget you must first add at least one child widget/control. That wasn't totally clear to me and I was trying to add the layout first.
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 have a simple qt application with a QTabWidget inside the main window. I also have a few QPushButton(s) and QRadioButton(s).
What I want is that when I resize the window either manually or by maximizing/minimizing it should resize the containers in the same way.
In other words, what I want is equivalent of DockStyle.Fill in qt C++
How can I do that ?
In Qt you have to use Layouts:
The Qt layout system provides a simple and powerful way of automatically arranging child widgets within a widget to ensure that
they make good use of the available space.
In short, all components in a layout will be relocated to new places after the window, to which the layout belongs, is resized.
If you are using deisgner:
1. Click the empty space of a widget to select itself(or a main Window, I use just a base widget here for demonstration), and the layout option will be hightlighted:
2. Choose a desired layout
Here is what object monitor looks like after a QVBoxLayout is used:
If your widget doesn't use layout, it will look like this:
What we have done here is to make the base widget/mainWindow equip a main layout. You can see that the buttons are automatically aligned, when you resize the widget, those component will be relocated according to the layout:
Perhaps you will find it nettlesome of those expanding space, so the next move is to add a Spacer to the layout; so when layout is resized, only the spacer will stretch.
(Another option is to make your widgets expandable, see ** at the end of this post)
3. Besides, you can add a layout into another to create a nested layout
For example, first I choose A and B (by pressing Ctrl) and use QVBoxLayout. This additional layout is not base layout and hence highlighted by red rectangle.
Then I choose C and the layout which contains A & B, and use QHBoxLayout on them,
Finally I use another QVBoxLayout as my main layout on the base widget, just like what we did previously.
And the object monitor:
If you like the special feeling of hitting keyboard and always handcraft the code:
For the last example:
QWidget *Form = new QWidget;
QPushButton *pushButton_A = new QPushButton("A");
QPushButton *pushButton_B = new QPushButton("B");
QPushButton *pushButton_C = new QPushButton("C");
QVBoxLayout *verticalLayout = new QVBoxLayout;
QHBoxLayout *horizontalLayout = new QHBoxLayout;
QVBoxLayout *mainLayout = new QVBoxLayout;
verticalLayout->addWidget(pushButton_A);
verticalLayout->addWidget(pushButton_B);
horizontalLayout->addWidget(pushButton_C);
horizontalLayout->addLayout(verticalLayout);
mainLayout->addLayout(horizontalLayout);
Form->setLayout(mainLayout);
Form->show();
In your case
Here is an example of layout:
Notice that QMainWidget has a centralwidget as a base widget. Besides, each tab of QTabWidget has it's own base widget (tab and tab_2 in the picture) which adopts another base layout.
*Don't forget to add Spacer in layouts to shape them as you like.
** You can set size policy on each widget (QTabWidget, QPushButton etc) to make them horizontally/vertically expandable or fixed, this cooperates with the layout strategy. For example, in the very begin example if we set
button A to be vertically fixed, horizontally expanding
button B to be vertically expanding, horizontally expanding
button C to be vertically expanding, horizontally fixed
It will look like this when resizing:
you need to look into how to use layouts in your application
http://qt-project.org/doc/qt-4.8/layout.html
As a quick and simple first try, in the Designer you can right-click on the main window, and choose "layout" from the drop-down menu. Here you can pick the grid layout, for instance.
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;
I have a QMainWindow whose central widget has been set to a QGraphicsView viewing a black scene (for test purposes). Note that in the code below, I use my class derived from QGraphicsView, called CQtGlView, which reimplements only the resizeEvent function.
Regardless of whether I add the view directly,
CQtMainWindow::CQtMainWindow() {
m_glView = new CQtGlView();
setCentralWidget(m_glView);
}
or stick it in a layout with margins of 0 in a dummy widget,
CQtMainWindow::CQtMainWindow() {
m_glView = new CQtGlView();
QWidget* dummy = new QWidget();
QHBoxLayout* l = new QHBoxLayout();
l->setContentsMargins(0,0,0,0);
l->addWidget(m_glView);
dummy->setLayout(l);
setCentralWidget(dummy);
}
I get an unwanted grey border around the widget.
The screenshot below illustrates the problem, visible between my scene and the windows aero border.
This would not be a problem if my application did not allow switching to full screen. The border is very obvious once the rest of the screen is black.
It's possible this area represents the DockWidgetAreas around the outside of the central widget.
Is there anything I can do to solve this other than not use QMainWindow? (Undesirable due to my use of menuBar, tool bars, and statusBar.)
It turns out that QGraphicsView derives from QFrame, where I assumed it was only a QWidget.
The solution to this problem was to call setFrameStyle(QFrame::NoFrame); in the constructor of my QGraphicsView subclass. Or if it was not a subclass,
m_glView->setFrameStyle(QFrame::NoFrame);
Have you tried setFrameShape(QFrame::NoFrame) on the QGraphicsView?