Promoting a top level widget using Qt Designer - qt

I am trying to promote the top level QWidget into a derived MyWidget class using the "promote to" menu in Qt Designer.
For that, i have defined the promotion with the "promoted widgets.." menu.
I have also add a child QWidget (in violet) to the top level QWidget and i was able to promote into it into MyWidget using the "promote to" option, that appear after a right click in the object inspector. (as shown in the picture)
But for the top level QWidget, the right click don't give access to the "promote to" menu and i have the same problem with a QFrame.
Is it possible to do that with Qt Designer ?
Thank you.

No, you can't promote top Widget in Designer. But you can do it manually. Simply open ui file in text editor and make necessary changes to the top level widget. Which changes you will need you can see in your child widget defenition. Just copypaste needed fields and values.

Related

QDockWidget form in Qt Creator Designer

I'm using Qt Creator 4.5.0 and am trying to create a QDockWidget that I could modify in the builtin designer (I do this all the time with QDialogs and QMainWindows, so this is the first time trying with a QDockWidget). But I'm having no luck with being able to add any widget elements of any kind to the QDockWidget.
Here are the steps I've taken
In the Projects tree on the left, right click on the project and select "Add New..."
In the window that pops up select "Qt" on the left side, then select "Qt Designer Form Class", then select "Choose"
On this page expand the section for "Widgets", then select "QDockWidget", then select "Next"
On this page give the class a name (for me it's "ImageFilesDockWidget"), then click "Next"
On this page select "Finish" to add the files to the project.
From here the "ImageFilesDockWidget.ui" file will automatically show up, so I tried to add some widgets to the view, but nothing would get added. For example, if I clicked and dragged a pushbutton into the center of the dockwidget, then it displayed a red circle with a line through it to indicate I couldn't add the item.
If anyone has run into this problem and knows how to make it work, then that'd be an immense help to me.
Thanks in advance.
update
Currently I'm able to use the designer to customize a standard QWidget object (call it "ImageFilesWidget.ui"). So at the moment my solution is to add a standard QDockWidget to my QMainWindow in the designer, then (still in the designer) I promote the dockWidgetContents from a standard QWidget to my ImageFilesWidget class.
It seems like the problem is when qtcreator 4.5 creates the dockwidgets ui file for you, it doesn't include the "dockWidgetContents" widget that is included in previous versions. Just manually put <widget class="QWidget" name="dockWidgetContents"/> under the "windowTitle" property of the dockwidget and you'll be able to add ui elements to it.

How do I add a QWidget designed in Qt Designer inside a designed QMainWindow?

I started developing an application, I designed a empty QMainWindow wit just the menu bar. and created two new QWidgets and designed the features of my application on each.
Here is the thing: How do I add and interchange the last two QWidgets inside my QMainWindow?, so QMainWindow will show one set of features of my application at once.
Perhaps you are looking for QStackedWidget
(from Qt: The QStackedWidget class provides a stack of widgets where only one widget is visible at a time.)
You can find it insde the Containers group
Add a StackedWidget into your MainWindow, then
Directly edit the widget at present page by Qt designer(use the upper-right arrows to switch between differetn widgets). Notice that
in StackedWidget you have to create another signal sender, ex: a
combobox to decide which widget should be shown), or
If your custom widget contains some customized and hand-crafted
funcationalites that Qt doesn't have, you might need the widget
promotion. (otherwise, skip this)

Qt: mainwindow application

I would like to build an embedded Qt application. This application shall have a couple of windows which are invoked by button click. I don't know if I understood the concept of using qmainwindow in the right way:
Do I create one QMainWindow class and each other window that should be displayed is a widget placed as central widget or is any new window I call a new QMainWindow?
I do not use qmainwindow's tool, menu or status bar just the dock widgets which surround the central widget, like a header on top and a button bar at the bottom or a widget to the reight like a keyboard. Since the header's label stays the same (only the title and the icon changes) and the bottom bar always holds some button (which should call another central widget or return to the previous one), changing the central widget should be sufficient right?
Have a look at QT Layouts
http://qt-project.org/doc/qt-5.1/qtwidgets/layout.html
Remember you can nest layouts, so you probbaly want a VBoxLayout, and the second entry in that layout will be a HBoxLayout.

How to use my treeview subclass in qt designer?

I have a class myTreeView which is a subclass of QTreeView, which I am using in other widget and doing layout manually. now I want to include myTreeView in the new widget using designer so that I can avoid layout code. any suggestions/reference, how to do this ?
Place a QTreeView into your layout in Qt Designer. Right click the QTreeView, click Promote to... add a New Promoted Class definition using the form at the bottom of the dialog.
i.e. specify the base class of your derived class as QTreeView, give the widget a name, and specify where Qt Design can find the header file for your derived class.
That should allow you, at a minimum, to place your widget on the form as you lay it out. It will most likely show up as a grey empty box (much like a QWidget) on the layout however when you compile and build a project using your .ui file your widget will appear.

How can I insert a widget into a mainwindow generated by Qt designer?

I have a Main window build with Qt Designer and I also have a widget built with Qt designer (both in a separate ui file). How can I instantiate my widget into my mainwindow at runtime?
The easiest way (using Designer) is to open your main window, drag a QWidget into it, and position/name the QWidget like you would your custom widget. Once that is done, right-click on the QWidget, and select Promote to.... A dialog will show up with the widgets it can be promoted to. At the bottom of that dialog, you can add a new widget for promotion. Type in the class name and include file information, and add that widget. Then select the entry in the list, and click the Promote button.
At the end of this process, you should be able to recompile, and your custom widget will be where you placed it in the main window.
Can't you use QMainWindow::setCentralWidget function?

Resources