Qt - Make QMainWindow to non resizible in Qt Designer - c++

Is it there a way to set a QMainWindow to be non-resizible in Qt Designer? I am seeing lots of coding examples but I want to do as much UI customization in Qt Designer as I can. So far I can only get this by setting the minimum size and maximum size to be equal, but still there is the resize arrow in the corner of the window and a "maximize" button on the top of the window.

When you select the QMainWindow, the properties of the object does contain a field for sizePolicy, both horizontal and vertical, as mentioned by the answer of #jester and you can set those to fixed.
I have found that doesn't always work and was never sure why (perhaps to due to layouts), but as you've found out, if you set the minimumSize and maximumSize fields to the same value, it does what you want.
As for the resize arrow and maximize button, I have never been able to do that from Qt Creator (designer), so I would say it's not possible. However, just one line of code is all you should need in the constructor of your class: -
setWindowFlags(Qt::Window | Qt::CustomizeWindowHint);
By default, the window flags include Qt::WindowMaximizeButtonHint. By setting the above flags, you're stating that you want to customise the window to include the specified elements. This will also remove the minimise button, so if you want that too, you should add Qt::WindowMinimizeButtonHint

I am not using Qt Designer; I am just writing a subclass of QMainWindow made from scratch. The solution I found for having a non-resizable window is to call setFixedSize on the QMainWindow after you have set up all your widgets and layouts. If you have set things up well, then you don't have to pick a size manually; you can just get the size from sizeHint. The line of code I used inside my subclass of QMainWindow is:
setFixedSize(sizeHint());
I tested this in Qt 5.5 on Windows 8.1 and everything looks fine: the maximize button gets disabled but the other buttons are still there, and the cursor does not indicate the possibility of resizing when the user moves it to the border.

use the setFixedSize property for the QMainWindow. In designer, if I remember correctly, you can set the horizontal and vertical sizePolicy to Fixed.

Sadly there is no option to do that; in VS you may find an option in the editor, to remove the mouse trigger that resize the window; but for some reason, QT5 does not have one.
I tried to use sizePolicy and set it as fixed for mainWindow; but this does nothing for both the horizontal and vertical policy.
To solve the problem, I did set my mainwindow minimum and maximum size as the same values; and when you run the application, the mouse cursor won't be enabled for resizing.
It is an ugly way to do something so simple, but this is the only way I found in QT designer, without use code.

I solved the problem of Qt5 which is displaying mouse arrow resize window even with window having fixed size, but in Python, but you can make modifications for C++.
MainWindow.setWindowFlags(QtCore.Qt.MSWindowsFixedSizeDialogHint)

It's an old post but I want to help if someone need it.
I found a way (not so beautiful) but it works directly from QTDesigner.
You can lock the resize by writing the values of height and width also inside "MinimumSize" and "MaximumSize" property.
Oviously also set "Fixed" on vertical and horizontal as told by other users.
This will remove the button to enlarge the window.

Related

Creating a scrollable window without Layouts

I am trying to achieve something what, I thought, would be a super easy thing to do. But for some reason QtDesigner is driving me crazy, it simply won't work...
I created a GUI and freely arranged different elements in the window, without layout or anything like that. At some point there were to many elements, so all I wanted to to, was to make it scrollable up and down, to see all elements.
So I added a ScrollArea in QtDesigner and added all elements as children of this ScrollArea (which btw also was a pain in the ass, because apparently drag and drop in the Object viewer is not a thing, and editing the .ui file by hand, is also not allowed... great).
So the result I have now is the following:
before resize - no scrollbar, elements at bottom inaccessible
resized vertically - some stuff still snapped off at the bottom
So as you see, although I created a ScrollArea... There is no scroll area. So I googled a little bit and found out that you can add layouts to your scrollarea, and yey, finally, a scroll bar! But how in this world am I supposed to arrange the elements in the way you see in the screenshots, with layouts. They are so super restrictive.
How am I supposed to simply get a vertical scrollbar, without this restrictive layout stuff?!
Here is how my object viewer looks
And here is what is called upon GUI creation:
ui->setupUi(this);
//setCentralWidget(ui->scrollArea);
//ui->scrollArea->setWidgetResizable(true);
I tried it with, and without the commented lines. No scrollbar, no matter what I do.
Try this to fix it:
In Qt Designer:
Select QScrollArea object.
Uncheck the QScrollArea properties widgetResizable.
In C++:
// If you want to set `widgetResizable` programmaticly
ui->scrollArea->setWidgetResizable(false); // Optional if you did it in Qt Designer
ui->scrollArea->widget()->adjustSize();

How to activate centralWidget in QT Designer

I was looking at this article
How to make a Qt Widget grow with the window size?
but when i got to the answer I got stuck on "activating" the central widget. I notice an icon with a red circle so I guess that means its disabled. I've been searching the net to try to figure out how to "activate" it but I am not having any luck.
Can someone please help me out?
Have a look at the layout system.
That icon does not mean your QWidget is disabled, that just mean you do not apply a layout on it.
Try to press like Ctrl+1 in order to apply a basic layout. If nothing has changed, you might need to put a QWidget inside the central widget first and then apply the layout.

QT window within window?

I'm setting up a small code editor using QT and following this example. However, i'm curious on how to create windows within windows or widgets within widgets. I'm trying to achieve something similar to these:
http://i.stack.imgur.com/Vn8Ut.png
http://www.hanselman.com/blog/content/binary/Windows-Live-Writer/Download-Visual-Studio-2013-while-your-f_1431E/image_4eb5427c-1ae7-4464-9c26-2282fe8d06c3.png
Is there an example of overlaying widgets like this?
Any alternative soloution for QMessagebox for IOS development (QWidget application only)?
I gave an example of getting another QWidget to be embedded and painted on top of another one. Let me know if you have any questions about how it was done.
The PopUp flag and Qt::Tool options are also relevant.
Be sure to check out: the ToolTip property of a QWidget and the WhatsThis property of QWidget.
http://qt-project.org/doc/qt-5/qwidget.html#toolTip-prop
http://qt-project.org/doc/qt-5/qwidget.html#whatsThis-prop
There are also other ways to make borderless, focusless windows that hover and disappear quickly on command. The Window Flags and Widget Attributes in Qt are very powerful when you are looking to modify Qt Widgets.
When you parent a Widget to another widget, it will draw itself on top of the other. Then you just need to resize and position it properly.
Also subclassing existing widgets can give you more options.
Draw text on scrollbar
Also common Qt::Tools that you will find are QDockWidgets. They are awesome!
Hope that helps.
Take a look at Qt Namespace especially Qt::WA_LayoutOnEntireRect and Qt::WA_StyleSheet. Pass it as a widget attrybutes. The second option looks promising but you have to create style sheet for QWidget.

QWidget Transformation

I am writing an application using Qt and would like to have a "Metro Style" interface. Everything is finished except I don't know how to make the widget appear and disappear. For instance, in WPF you can animate (UIElement.RenderTransform).(TranslateTransform.Y) so that Y becomes zero or negative. How can I move the QWidget in a QGridLayout so that it can hide?
Example:
After doing some research I figured out a way to do this. Instead of letting Qt do the layout I simply handled it myself via move and set width/height functions. Overriding resizeEvent made it so I could update the values in case the window was resized. Additionally I used setMask to ensure that the widget did not leak over to unwanted locations in the UI.

mouse over transparency in Qt

I am trying to create an app in Qt/C++ with Qt4.5 and want the any active windows to change opacity on a mouseover event...
As i understand it, there is no explicit mouseover event in Qt.
However, I got rudimentary functioning by reimplementing QWidget's mousemoveevent() in the class that declares my mainwindow. But the mainwindow's mousemoveevent is not called whenever the mouse travels over any of the group boxes i have created in there (understandbly since QGroupbox has its own reimplementation of mousemoveevent).
So as a cheap work around, I am still using the mousemoveevent of my mainwindow but a query the global mouse position and based on the (x,y) position of the mainwindow (obtained through ->pos()) and the window size (-> size -> rHeight and rWidth), I check if the mouse is within the bounds of the area of the mainwindow and change the opacity thus.
This has had very limited success. The right border works fine, the the left changes opacity 4 pixels early. The top does not work (presumably because the mouse goes through the menubar and title bar) and the bottom changes way too early.
I thought of creating an empty container QWidget class and then place all the rest in there, but i felt that it would still not solve the big issue of the base widget not receiving the mousemoveevent if it has already been implemented in a child widget.
Please suggest any corrections/errors I have made in my method or any alternate methods to achieve this.
p.s. I doubt this matters, but I am working Qt Creator IDE, not Qt integration into VS2008 (it's the same classes anyways - different compiler though, mingw)
Installing event filters for each of your child widgets might do the trick. This will allow your main window to receive child events such as the ones from you group boxes. You can find example code here.
You may be interested in Event filters. QObject proves a way to intercept all events zipping around your application.
http://doc.trolltech.com/4.5/eventsandfilters.html#event-filters
If I understand what you are attempting to do, I would reimplement the widget's enterEvent() and leaveEvent(). The mouse enter event would trigger the fade-in and the leaveEvent would trigger the fade-out.
EDIT: After re-reading several times, I'm still not sure what you are trying to accomplish. Sorry if my suggestion doesn't help. :-)