[Slate] SComboBox doesn´t update laben OnSelectionChanged()

Development Programming & Scripting C++
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1

Hey guys,

I´m having a hard time understanding Slate and its update behaviour in an editor plugin.

I have a SComboBox which shows a few categories. If I choose another option my OnSelectionChanged
event gets fired but the label on the checkbox doesn´t update.

Am I missing something how Slate draws itself? Do I need to “redraw” the UI?

If anybody can guide me to a proper guide on how to setup a Editor Window which has a lot of dynamic changes I will be forever grateful.
Having a hard time to find good documentation for Slate in the editor.

Example code:


void SCategoryComboBox::Construct(const FArguments& Args, std::vector<Category> categories)
{
	setItems(categories);

	ChildSlot
		
			SNew(SComboBox<TSharedPtr<Category>>)
			.OptionsSource(&Categories)
			.OnSelectionChanged(this, &SCategoryComboBox::OnSelectionChanged)
			.OnGenerateWidget(this, &SCategoryComboBox::MakeWidgetForOption)
			.InitiallySelectedItem(SelectedCategory)
			
				SNew(STextBlock)
				.Text(FText::FromString(SelectedCategory->Name))
			]
		];
}

void SCategoryComboBox::OnSelectionChanged(TSharedPtr<Category> newSelection, ESelectInfo::Type)
{
	SelectedCategory = newSelection;
}

TSharedRef<SWidget> SCategoryComboBox::MakeWidgetForOption(TSharedPtr<Category> inOption)
{
	return SNew(STextBlock).Text(FText::FromString(inOption->Name));
}

Thanks! :slight_smile:

2

Still couldn´t figure it out. Bump!

3

having same code and same propblem in 2025

4

SComboBox doesn’t update the text automatically. You need to update the text yourself when selection changes. Use SAssignNew to store a reference to the text when constructing the widget. Then set its text when selection changes.

5

Tank you mate, i used textlambda to update it