Is it possible to have QGridLayouts within another QGridLayout? I have been trying to do this using the UI designer, so that I can resize all QGridLayouts uniformly.
This is for an Ultimate-Tic-Tac-Toe game I am creating for fun.
Here, I have nine QGridlayouts. I want to group them together. If I want to expand the boxes, I have to go through each one and expand them. Or I have to copy/paste the first box and make sure they are all aligned again.
I tried selecting all of them and clicking Lay Out in a Grid , but that messes up how they are displayed. Especially the lines that separate the layouts. Am I not doing this correctly?
This just looks weird:
Yes, there is no any problems inserting QGridLayout into another QGridLayout. Here is a demonstration how it can be done in the designer.
Pay attention that there are no any lines when you open the widget in the Preview: they are visible only for design purposes.
Buttons are added to the layouts just to see how they are places in the Preview.
Related
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();
I would like to enable mouse-selection of the text of several QLabels arranged in a grid layout in a Qt GUI.
A QLabel has textInteractionFlags like TextSelectableByMouse which enables this behaviour for one object, but a selection across several QLabel widgets does not seem to work.
Is there a way around this that does not require a lot of mouse "tracking" or reimplementing a layout?
I fear there's no simple method to get what you want. The first problem would be what you'd expect to find in the paste buffer after selecting some rectangular section of your table. How should the label texts be delimited, should they be organized by row or colum?
You may say that you want them row-wise, columns separated by blanks and rows ending with a \n, but that doesn't need to be what the next person needs.
You may want to spend some time considering QTableView or QTableWidget.
this is a question for programming with Qt/C++. I have a combo box with two items. If current index for selection is 0, then no QLineEdit should be displayed in layout below the combo box. If it is 1, a QLineEdit should appear. It should disappear again if index is 0 again.
Notably, other elements in the layout should not be affected by the change. Values already entered by user in other QineEdit should remain in place.
Is it possible to dynamically modify widget? How did you procede?
Kind regards.
All QWidget objects have a function called hide().
You can attach a signal to the currentIndexChanged signal of the combo box, and in that function you implement whatever logic you have in mind and invoke the method hide of your QLineEdit.
The only problem with this approach is that a Qt Widget, when hidden, doesn't occupy any space on the screen, and this can lead to layout changes (depending on how you've programmed your layout, some other widgets can move a bit, for example). To prevent that you can make another Widget appear where the QLineEdit were (perhaps invoking the show() function, and placing the 'placeholder' on the same container that the LineEdit was), only to occupy its space and keep it there, or you can use a QStackedWidget add the two Widgets there and change its index.
I would recommend that you read the following example, it has some useful insight on dynamically changing things: Qt Extension Example.
Also, when in doubt, take a look in the other examples, they are really well documented and cover a lot of important topics on Qt.
Good luck with your code :)
I am having a problem redrawing a QWidget window after its size has been adjusted. I have tried update(), repaint(), adjustSize(), but all seem to suffer from the same thing: only part of the window is redrawn, resulting in the window frame on the bottom and right sides to not show. The window is also not resized entirely.
Just in case it makes a difference, the window is in a QMdiArea.
Thanks.
// ... some subwidget resizing and moving.
calibrationWindowUIs[activeWindow].layoutWidget2->move(QPoint(oldXLeft, 30 + height + 21));
calibrationWindowUIs[activeWindow].layoutWidget1->move(QPoint(oldXRight, 30 + height + 21));
// Set window size.
calibrationWindows[activeWindow]->setMinimumSize(calibrationWindowUIs[activeWindow].tabWidget->geometry().width() + 40, calibrationWindowUIs[activeWindow].tabWidget->geometry().height() + 40);
calibrationWindows[activeWindow]->update();
Note: I'm new to Qt; perhaps I'm doing something wrong with layouts?
Edit: I may have not given enough information. Alright, to be quite honest, I still have to delve deeper into layouts and related material. What I had tried to do here was to use Qt Designer in order to design the window. I've done what perhaps amounts to a stupid mistake: I didn't use an overall parent layout for the entire window, but hacked it with a couple of smaller layouts that I therefore have to move about and resize individually. See the Qt Designer screen (the red rectangles are the sole layouts): .
What is happening is that in the frame to the right, I am playing a video clip that can be of various resolutions. I want the frame to resize depending on this resolution, which also means that the buttons and window have to move/resize accordingly. That is where the window resize comes in. I'm sure there is a more elegant solution than what I am doing here, but I am trying to handle several other scenarios here and hence the lack of quality of code.
The result is that when I load a clip, the window attempts to resize, but does so badly; the following is the result:
If the window is dragged, it 'pops' into its correct size; in the meantime, however, it just looks ugly.
A couple further questions: do you use the Qt Designer to design your UIs? I found that programmatically you can achieve much better control of your interfaces. One thing which I could not do in the designer was to have a layout parented by the main widget, i.e. the equivalent of having the following bit of code:
QVBoxLayout* layout = new QVBoxLayout;
this->setLayout(layout);
A layout placed in the designer always seems to create this 'layoutWidget' subwidget, which the layout you placed is then parented to. Any way around that?
We use a mix of designer and code to create layouts, the Qt layout system can be very unintuitive at times. But I would probably not layout a full series of tabs in one designer ui file, i would make each tab each own widget and then assemble them either through code or in the designer by promoting to custom classes. This gives you better separation of responsibilities, by putting all the functionality of all the tabs into one file you almost guarantee a large unwieldy class.
When a widget has child widgets in designer you can assign a layout to it by adding it from the context menu. Make sure nothing is selected and click on the background of the widget in which you want to create a layout, select the layout and all of the widgets children will be assigned the layout.
What does help is creating hierarchies of layouts. Looking at your first screenshot, i would probably use a vertical layout with spacers on top and bottom for the items on the right, an horizontal layout with spacers left and right for the button bar and a grid layout for all the items together. Without the spacers your items will extend when the window grows. The spacers will let you control the behavior under resizing better.
you are calling setMinimumSize(). That's fine, but you should also call resize()
How do you change the behavior of a QListWidget so that it resizes its height instead of choosing a (seemingly arbitrary) height and adding scrollbars? See screenshot:
The QListView's should fill up as much space horizontally as they can (creating as many "columns," if you will.) Then they wrap and make as many rows as necessary to fit all the items. These calculations should be adjusted as the window is resized. This is all working fine.
However, what I want to happen is that instead of the height staying the same, the QListView should grow or shrink vertically and never need any scrollbars. The scrolling, if necessary, will be handled on the parent QWidget that hosts all of the labels and lists. It seems like once the height of the QListWidget is established (not sure where its default is coming from), it never changes. It is too big in some cases (see second "Test" list above) and too small in others (see first "blank maps" list above.)
The layout above is nothing surprising: two QLabel's and two QListWidget's in a QVBoxLayout. Here are the properties I have set on the QListWidget's:
setMovement(QListView::Static);
setResizeMode(QListView::Adjust);
setViewMode(QListView::IconMode);
setIconSize(QSize(128, 128));
(I already tried setting the horizontal and vertical scrollbar policies, but that just turns the scrollbars off, clipping the content. Not what I want.)
Maybe you could this without using QListWidget. The Qt's examples contain a new layout class, QFlowLayout, which could be useful. With the following kind of widget hierarchy you could get multiple groups with labels and they all would be inside one QScrollArea.
QScrollBox
QVBoxLayout
QLabel "Blank maps"
QWidget
QFlowLayout
your own widgets showing map images and labels
QLabel "Text"
QWidget
QFlowLayout
your own widgets
The problem is that this kind of solution would create much more widgets than QListWidget based solution. So if you have hundreds of items in your list, this might not be the best solution.
There is a protected member function called contentsSize() in QListView. It is used to calculate the required minimum(), maximum(), and pageStep() for the scrollbars (as mentioned here).
Can you subclass the QListView class and make use of that information? I suggest you recalculate the size of your widget in the same function where you add contents to it. While somewhat lacking elegance, this appears to be a pretty reliable solution.