To keep the question as simple as possible, I prepared a simple Qt designer form below
There is a Tab Widget on the left side and empty QWidget on the right side, the QWidget as a GroupBox. The Groupbox has a radio and pusbuttons (you can see them on Object inspector window on the photo as well ). The tab widget has a line edit. The central widget has a gridlayout and horizontal qsplitter is used.
My issue is that when I enlarge the window, all items (lineedit, radiobutton, pushbutton) are on the fix position. Here is an example what I mean:
What I want is that when the window is enlarged the items should be placed on the bottom of the window, or if they are in the middle, then they should stay in the middle. ( I don't want size of the buttons/lineedits to be changed).
How can I do it?
The items you want to move dynamically, with window resizing must be in a layout.
So, in the example you've posted, you need two layouts; one inside the tab widget, for the QLineEdit and at least one in the GroupBox for the radio button and push button.
If you want the radio and push button to be aligned horizontally, you can start by placing them in a horizontal layout, before placing that layout in another, which all reside in the group box.
When you start to add items to layouts, such as push buttons, you'll start to notice that they can get stretched, so you may need to set the size policies of the widgets.
If you want the line edit to be centered horizontally, you will have to place two horizontal spacers on each side of the line edit and select the three together and set "Lay out Horizontally". This can found at the top toolbar in Qt Designer.
To always have it at the bottom of the tab widget, put a vertical spacer above the line edit in your tab widget. Then select the option "Lay out vertically" for the tab widget.
The same goes for your radio button and push button. Keep them in a horizontal layout, with horizontal spacers if required and put a vertical spacer into the group box and set the layout property for the group box as "Lay out Vertically".
Most important of all, I suggest you go through some basic tutorials before you continue. Here is a link to a good channel on youtube.
https://www.youtube.com/playlist?list=PL2D1942A4688E9D63
If you don't have a layout in your tabWidget or GroupBox:
You must set a layout (for example QVBoxLayout) inside your tab widget and a group box.
It can be done using QtDesigner. It also can be done in code like this:
QWidget *window = new QWidget;
QPushButton *button1 = new QPushButton("One");
QPushButton *button2 = new QPushButton("Two");
QPushButton *button3 = new QPushButton("Three");
QPushButton *button4 = new QPushButton("Four");
QPushButton *button5 = new QPushButton("Five");
QHBoxLayout *layout = new QHBoxLayout;
layout->addWidget(button1);
layout->addWidget(button2);
layout->addWidget(button3);
layout->addWidget(button4);
layout->addWidget(button5);
window->setLayout(layout);
But if you do, and then you want your buttons to stay at the bottom:
Then you have to try setRowStretch method http://qt-project.org/doc/qt-4.8/qgridlayout.html#setRowStretch or take a look at QSpacerItem.
Related
I am trying to have a QSplitter accept QDockWidgets in my application. So far, I have done everything through the Qt Designer and what I have done is create three individual QWidgets. I then select all three of the QWidgets and I right click on them and select Layout->Lay out Vertically in a Splitter.
This lays all three of the widgets in a splitter quite nicely. I then drag a Dock Widget to the Object/Class Window in the top right and set them in the Splitters Widget. This places the QDockWidget happily inside the widget. However, when I fire up the program I cannot click and drag the dock widgets. If I double click the dock widget, the dock widget will pop out, however I cannot place it back since it was never technically docked. Which then creates the problem of the widget not being allowed to dock anywhere else. It cannot be docked on the QMainWindow class or in the QSplitter class.
Is there anyway to have a QDockWidget docked inside of a QSplitter and have the functionality of a QDockWidget?
After you add the dock widget to the QSplitter, the widget has become part of the splitter.
You can try checking like this
//If sure of Dockwidget at zeroth position
QDockWidget *widget1 = (QDockWidget*)ui->splitter->children().at(0);
A Dockwidget has a feature of floating as a top level window.
But you can make a dockwidget look like other widgets by setting QDockWidget::NoDockWidgetFeatures
Either:
Go to the object window in Qtdesigner (top -> right)
And select the dock widget added to splitter.
In proeprties window, down below scroll down and look for "features".
Then uncheck the features like movalble, closable etc....
I made it NoDockWidgetFeatures.
or
You can set programmatically using setFeatures(QDockWidget::NoDockWidgetFeatures)
In a Qt Widget Application, I'm trying to make the following:
My aim is to have a form with a scrollArea with a vertical layout and each item in the scroll area aligned at the top.
Unfortunately, it's only staying in the centre shown here:
I've tried selecting the scrollArea and chaninging vertical alignment from AlignVCenter to AlignTop, but this seems to have no effect.
How can I align all the content to the top of the scroll box?
You can use a QListWidget to hold a list of not only just text, but also QWidget's (such as push buttons, line edits, etc).
Simply add a QListWidget to your window, and in C++ add the widgets to the QListWidget as needed.
Here are some steps to insert a button into your QListWidget:
Create a QListWidget item into your application.
change selectionMode = NoSelection and focusPolocy = NoFocus
Put the following C++ code into your application:
// Create list item
QListWidgetItem *listWidgetItem = new QListWidgetItem();
// Create widget
QWidget *widget = new QWidget();
QVBoxLayout *verticalLayout = new QVBoxLayout();
verticalLayout->setSizeConstraint(QLayout::SetFixedSize);
widget->setLayout(verticalLayout);
// Add button to widget layout
QPushButton *pushButton = new QPushButton("Button!");
verticalLayout->addWidget(pushButton);
// Add list item to ul->listWidget
listWidgetItem->setSizeHint(widget->sizeHint()); // Set the size of the list item to the same as the widget
ui->listWidget->addItem(listWidgetItem);
ui->listWidget->setItemWidget(listWidgetItem, widget);
Old answer:
I found my answer here but I will re-post it for anyone else interested.
To align elements at the top of a scroll area, add a vertical layout as a child to the scroll area and put all your elements inside that vertical layout. Like so:
In your C++, add a spacer item to your vertical layout inside the scroll area by using addStretch():
ui->verticalLayout->addStretch();
All the items should now magically be aligned to the top.
Edit:
This seems to only work for the very first item, and all other items are not pushed up to the top.
Why does the widgets inside a QTabWidget don't resize?
All my widgets resize except for the ones inside the tabs, even the tabs resize, but not the items inside it.
Is this because of the type of layout as I show in the figure?
I can's assign a layout to it. this is before and after maximizing the window.
Why can't you assign a layout to it? You just have to give each tab a layout. Drag your widget into the tab. Select the tab, not the widget, click on one of the layouts in the top row of the designer. Your widget will fill the whole tab and resize nicely.
In my Qt program, I programmatically generate a modal QDialog. I want to show two widgets in this dialog window: A custom widget showing a camera output and a QTableWidget, showing the pixel coordinates of the corners found in the camera image. I generate a QHBoxLayout and add my custom widget and the QTableWidget into it. Then I set this QHBoxLayout as the Layout of the QDialog window. What I want to achieve is to share the available space in the QDialog's window area equally between my custom QWidget and the QTableWidget, horizontally, by using a QHBoxLayout. But I always end up with QTableWidget occupying the whole QDialog area, by overlapping my custom widget. How can I instruct these two widgets to exactly share the QDialog area?? Note that I first add my custom widget and then the QTableWidget into the QHBoxLayout.
Make sure on your custom widget you've specified a minimumSizeHint and a sizeHint, this instructs the QLayout manager that the widget requires a specific space. To have them split equally you'll be best off detecting the size of the QDialog and then specifying the width for both by removing the boundary sizes (spacing between widgets + space to QDialog edge) and dividing it up.
In my MainWindow ,menuBar contents and toolBar contents are few that it will occupy only a small portion in the left side off the main window and the rest of the portion is left empty.
Im having a info frame with some widgets in it in the right side of the centerwidget.
my question is that can i use the the info frame from the menu bar space itself
as menubar and toolbar can occupy only left portion of the mainwindow and i can use the entire right portion for info frame..?
You can't use that space through layout because this space is already taken by the main menu and the toolbar. There is no option to put something in this space.
But you can add a main window's child without putting it in any layout. It will be shown above all layed out children. But you will have to calculate and adjust size and position of this widget manually.
For example, add the following code to the main window's constructor:
QPushButton* b = new QPushButton("TEST", this);
b->move(200, 0);
It looks like this: