I'm trying the elements on a window resizable so I need to add a layout to it, but all the options in qt designer are greyed out
You need to select 2 or more elements to unlock those options. Actually they are for a group of elements so that you can add layout to any group of elements.
Related
So I currently have got a custom widget, and I want to add them to the main window after clicking a button. I would like to add them all to one fixed position first and then I will be able to drag them wherever I like. I am able to create and display these custom widgets with help of QHBoxLayout or QVBoxLayout, but in this case they will not be in the same position after I create them. Any help will be appreciated!
As the names suggest, the QLayout classes manage the position and geometry of the items added to them. You cannot move (eg. drag) an item out of a layout w/out first removing it from the layout (QLayout::removeItem() and derivatives). For example when you drag a toolbar or dock widget out of a QMainWindow it goes through all sorts of machinations to remove it from the MW layout, change the widget's window flags, remember the old position in the layout, and so on. And the reverse to dock it again.
To do what you describe (drag widgets arbitrarily around a window) you would need to not use a QLayout and position the widgets manually by specifying a QWidget::setGeometry() for example. After initial position, and assuming the user has some way to grab the widget (title bar or drag handle you made, etc), you'll probably still need to manage their positions, for example if the main window is resized (if you care about keeping them contained). Essentially you'd have a bunch of separate widgets acting as individual windows and probably need some way to keep track of them.
I don't know what kind of widgets you're talking about, but one option may be a QMdiArea which lets the user drag windowed widgets around, tabify them, save/restore state, and so on.
For more flexibility you could also look into the Qt Graphics Framework. The graphics scene has a lot of features for user-movable items/widgets, keeping track of them, and so on. It is probably the most flexible method overall, and you can also use regular QWidgets inside a graphics scene.
A couple other Q/A about arbitrarily positioning widgets (I'm sure there are more to be found):
QPushButton alignment on top another widget
How to keep Push Buttons constant in relative to change of Label Size in PyQt4
I want to allow a user using my application to be able to drag a boundary between two widgets in my window which will resize the two (i.e. you drag it down and the top one will get bigger while the bottom gets smaller, and vice-versa).
Is there anything in Qt designer that will allow a user to resize an element in the window, within certain constraints?
Thank you
What you're describing is called a QSplitter widget. In Qt Designer, you can create one by selecting 2 or more widgets, and then clicking the splitter button on the toolbar at the top. It's in the same location as the layout buttons. It will place those widgets inside a QSplitter. You still need to place the splitter widget inside another layout. It will create a handle between them to let you resize the portion that each widget gets.
You're looking for the QDockWidget. It can do all that you described above and more. The user can dock the widget to different sides of the window, changing which widget is on the top or bottom. You can customize the minimum and maximum sizes, as well as default sizes.
I use grid layout (horizontal and vertical too). I like the fact that when resizing the window fills the entire window contents. but this extension is poorly managed. I often want to change the size of only one column in grid layout without changing the size of the window. such as in Windows Explorer. there are two columns - the left list of directories and their contents to the left to the right. and i can always press mouse button therebetween and pulling change the mutual sizes of columns in relation to each other.
how can I do this in Qt?
You need to use a QSplitter rather than a QGridLayout in this specific case (where you just want 2 widgets shown together). QSplitters are draggable.
You are looking for QSplitter
(The following is the procedure in the Qt Designer)
Group your widgets, and click Lay Out Horizontally/Vertically in Splitter
Put this group into another layout (QGridLayout, for example) to automatically expand it.
Congrats! Your Layout is now draggable(from step1) and expandable(from step2).
I am using Qt Designer, and I would like to move a couple of top-level widgets into a horizontal layout.
I have dragged a "Horizontal Layout" object into the form. I am now attempting to drag the desired widgets into the layout.
Unfortunately, the new Horizontal Layout widget is infinitely thin:
... and I cannot drag my "Import Progress" label widget or my progress bar widget into the new horizontal layout widget.
Note that when I attempt to drag the desired widgets over the new horizontal layout widget, Qt Designer does not do anything useful for me in terms of expanding the drop region to make the horizontal widget available as a drop target. So I'm stuck.
How do I add widgets to an infinitely-thin layout widget in Qt Designer?
Select the layout, and then drop the widget onto the corresponding selected item in the Object Inspector pane. If you find it tricky to select the layout on the actual form, you can also select it via the Object Inspector pane.
One way (that I usually do as a workaround for not having to show the structure panel) is to select the layout, setting the top or bottom margins to any value (10, whatever) and then dragging the component into the layout. Yeah, that is just for the pure pleasure of dropping the component in the layout, i know, but is a way.
My small trick:
Select layout
Change temporary "layoutTopMargin"
Drop into layout required widgets
Restore layoutTopMargin to default 0
I have a ComboBox in Flex with about 20 items. How do I display all of them in a dropdown with no scroll bar? Right now, Flex displays 5 at a time in the dropdown and puts a scrollbar to scroll for more.
Here's an example:
http://blog.flexexamples.com/2008/07/18/setting-the-dropdown-menu-border-thickness-and-border-color-on-a-combobox-control-in-flex/#more-711
How do I make the dropdown bigger in this example so it shows all 10 items at once?
Found it: 'rowCount' is the property to change. It defaults to 5.
For ones who search for same thing for spark combo:
for spark components that extend SkinnableDataContainer (including ComboBox) you can specify layout with
requestedMinRowCount , requestedMaxRowCount
properties, and do as much changes as you want with the help of skin(this layout directly goes to DataGroup skinpart inside skin).