I would like to disable an item in a combobox in my Win32 application (C++). I'm not quite sure how to do this. I'm trying to achieve something that looks like this:
Notice how CollectionItem2 and 3 are greyed-out.
Any help would be very much appreciated!
If you truly need a combobox for this, then (as #IInspectable said) you'll need to do a custom drawn control. Basically, you'll have to store some information saying which items are disabled/grayed, and draw the items appropriately based on whether they're enabled or not.
There may be a somewhat easier way though. This is normally done with a Split Button. This is button with the BS_SPLITBUTTON style set. When the drop-down part of the button is clicked, it sends a BCN_DROPDOWN notification.
You normally respond to that by displaying a menu, typically using TrackPopupMenu to display it immediately below the button (or immediately to its right, if you prefer). This is a normal menu, so it can have items enabled, disabled, grayed, have check boxes, etc., as you see fit.
If you're using MFC, it has a CSplitButton class that wraps the Split Button, simplifying the code a little bit--you can pass an identifier of a menu and sub-menu when you create the CSplitButton object, and it handles things from there.
A sample result probably looks pretty familiar:
Note: MFC also has a CMfcMenuButton class. This has roughly similar functionality, but is somewhat clumsier to use. If memory serves, it is compatible with older versions of Windows (but the split button goes back to Vista, so it's fine unless you really need to support XP).
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I'm writing a GUI using QT for embedded system with linux. This device has no mouse. Only display and specific keyboard with keys: up, down, return and 7 number keys.
The software will be used to set some parameters of device and read them (some charts also).
Example of how menu could look:
after OPTION 1 selected
After SUBOPTION 1 selected some table with data is loaded.
Sometimes after selecting option i need to load specific widget and sometimes just another set of options.
I think it is possible to implement custom labels and kind of list widget that aligns them.
I guess it is also possible to use Qt's MVC classes for it. They are highly customizable, but i never made custom views and delegates.
Maybe i just need to create QtListView with stringlist model and apply stylesheet to it so it gets look more like buttons. And based on selection in list load next widget.
Which way is better and why?
Is there any easier ways to accomplish this?
Any ideas would be appreciated.
I want to know that whether I can add a textbox or label by changing the options in combo box. For example, I have 2 options in Combobox. If I choose the #1, it must show me 2 textboxes, but if I choose #2 it must show 3 textboxes.Can I do something like this in Visual Studio C++?
This can be done in two ways:
Dynamically create and destroy the edit controls using CreateWindowEx and DestroyWindow.
Statically create your GUI with 3 edit controls and set the visibility of the controls based on the selection using ShowWindow.
Have as many text-boxes you want. But hide them.
Handle CBN_SELCHANGE (ON_CBN_SEL_CHANGE in MFC).
In the handler, show (or hide) the text boxes depending on selection.
Showing/hiding text boxes aren't good from UI perspective. You better enable/disable them appropriately. You may put alternate text when they are disabled, and bring back original change when they have to be enabled.
Creating textboxes at runtime, and then deleting them isn't' good approach. You will need to keep track of Win32 UI handle and/or MFC object. This approach will also need more of UI resource creation/deletion, parent-child relationship handling et. al.
i need to hide tabs from a existing project in QT, i don't want to delete the code because i have to set parameters on that code, the Application relay on that too. Seems like QT hasn't built-in hide(); function, i tried to edit stylesheet to make it smaller, but doesn't work too, i've looked on the internet and seems like this is a known issue. Does somebody have some tricks to avoid this?
Only thing i was able to come up with is:
ui->TabObject->setEnabled(false);
basically i disable objects in the tab to make them not usable by the user, but this is not a good thing for the whole UI.
Maybe by calling QTabWidget::removeTab(index) - this removes the tab from the QTabWidget, but does not delete the tab's QWidget.
Is there any straightforward (without listening to key events) way to display the list of opened tabs in Qt, like following (in Visual Studio). I just want to make sure Qt does not offer such a feature, before implementing such a widget by myself.
At least in a primitive way like in NotePad++ (meant no offense). Now, when I am using QTabBar and press Ctrl+Tab it shows something like this,
And I don't know actually what is that !
The default behaviour of ctrl-tab is to cycle through the tabs. You will need to customize that to display your own dialog. You don't need to connect to any signals to do this, simply pass a reference to the tab widget/bar into the dialog. You can then use that reference to retrieve the names and to change the tab.
I have a map application and a submenu which has dynamically added objects (i.e. points on a map) added to the submenu, depending on the layer that is loaded. I have the ability to hide each individual objects (i.e. a point) by clicking on the corresponding submenu item. Is there any way to organize the submenu? When there are a lot of points (i.e. 100) the entire submenu takes up the screen. Can I add a scrollbar to a submenu? I looked in the documentation, but couldn't find anything that support this feature.
From this bug report I was able to find out that you could do the following:
submenu->setStyleSheet("QMenu { menu-scrollable: 1; }");
Works like a charm.
There is no such possibility as far as I know.
Maybe you shouldn't use a sub menu for this but prefer a menu entry that show a Point manager GUI of your own which would have a QListWidget displaying all your points items.
I'm aware that this solution will break a (big?) part of your code but I don't see anything else.
I think you may be able to get the effect you want by creating and using your own QStyle subclass (via QApplication::setStyle()), and overriding the styleHint virtual method to return 1 when the StyleHint parameter passed in is SH_Menu_Scrollable. At least, that works for me when I create large QMenu objects and show them as popup menus.... It may also work for QMenus attached to the menu bar, but I havent tried that.
Whilst it is possible by subclassing the QMenu class to create a custom widget and going from there you're better off looking at a better way to display that information. You'll save yourself time and it'll be much easier for your users to not have to scroll through a big list of items in a small area.