I have a QTabWidget with several tabs, every tab containing a QTableWidget with numbers. Outside of this QTabWidget, I have one button. When the button is pressed, the currently selected widget should be processed. The QTableWidgets are identical in their structure, they just display numbers, and if I have a pointer to one of these widgets, I cannot deduce which tab it came from.
A simple method to identify which widget is currently selected is to call currentIndex(). But this will break when I reorder the tabs in the designer and is probably not working with movable tabs.
Another way is to use currentIndex() and tabText(int index). Like this I have a stable way to find out which tab is currently selected. The disadvantage of this is that I am then dependent on having unique tab texts, and I in general don't like to rely on a UI property to implement functionality.
My solution for now is to give every Widget a different accessible name that I can then read out like this:
QWidget* widget = tabWidget->currentWidget();
QString* name = widget->accessibleName();
This works, but I wonder if there is a better solution, something like the Qt::UserRole that can be assigned to any cell in a QTableWidget.
Related
Hello fellow developers!
I want to realize a "Action" QCombobox where the different options trigger an action instead of choosing an option. The combobox says something like "Add Property" and when the user clicks it, he gets the different properties to choose from. If the user clicks one of them, it is added to -whateverdoesntmatter-. The combobox than switches back to it's original state.
The problem is, that the first entry "Add Property" is shown on the combobox's drop down, causing a little bit of confusion for the user since it is not really an action.
Normal state:
[Add Property]
Drop-down state:
[Add Property]
Add Property
Length
Width
etc ...
Therefore, I want to hide the first option as soon as the combobox drops down to achieve this behavior:
[Add Property]
Length
Width
etc ...
I have already tried with subclassing the combobox and overwriting showPopUp() and hidePopUp() - but I could not figure out how to get my intended behavior.
Ideas? Thanks!
If you don't absolutely need a QComboBox you might be better/easier off using a QToolButton with a QMenu associated and then set the button's popupMode to an appropriate value.
You may even use a QToolBar. Simply add a QAction with your desired label (like Add Property), associate the menu to it via QAction::setMenu and at it to the toolbar. The toolbar will automatically create the tool buttons itself.
To access the popupMode property you can use QToolBar::widgetForAction and cast it to a QToolButton.
I'm creating a control that can be used for manual inspection of Tesseract-OCR's output.
Currently I've implemented it as a custom widget, where I do all the drawing (I use a QScrollArea to handle the scrolling at least), and it looks like this:
As you can see, the images are "flowing", like word-wrapped lines in a text editor, and I use the space below the header text, so I don't have 2 clearly separated columns.
Now, it was suggested to me that using a custom widget is 'reinventing the wheel', but the problem is, I don't see a clear way to customize one of the existing container widgets enough to look and behave like this, that would involve significantly less effort or code. Neither is it clear at all to me what is the best way to do it. At most, I can think of using a QListWidget with owner-drawn items and variable item heights.
Am I wrong to use a custom widget here?
I'd like to put multiple widgets in one cell of a QTreeView. QTreeView already does this with check boxes (e.g if you set ItemIsUserCheckable and ItemIsEditable). For example, how would I show a small tool button next to a line edit, instead of the check box next to the line edit?
I've gone through the whole deal of subclassing Qtreeview, implementing a custom ItemDelegate, and overriding paint( ) and createEditor( ). And that works if I only need to render simple things, like a single line edit, single button, etc. However, I cannot get it to work for nested components.
I tried to create a QHBoxLayout, add a QLineEdit and a QToolBarButton to it, add the layout to a new QWidget, and return the whole thing from createEditor( ). However, nothing shows up.
Can anybody provide a simple example?
Thanks!
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.
I'm trying to get one cell in a QTableWidget to be a box with button at end"..." with file selector, but don't know how to change what kind of widget the cell is.
To control the types of cells in a table, it's best to use the QTableView class. Then, by using QItemDelegate you can make some table cell a button, to which you may bind a signal that opens a dialog.
I recommend starting by reading about delegate classes in the Qt docs.