Selecting Item in Content Browser triggers Plugin window widget refresh. How?

Hello, iam new to the C++ part of UE4.

I made a standalone window plugin.
It is for spawning static mesh actors according to a text file with coordinates.
It works fine already but i want it to be more intuitive.
So i want , when the user selects an asset from the content browser, that the asset name is shown in the plugin window.

I have this kinda working already, BUT, only if i close and reopen the plugin window.

So how do i update .Text(WidgetText) whenever a new Asset is selected in the Content Browser?

Main window function:

TSharedRef<SDockTab> FXSI2UE4Module::OnSpawnPluginTab(const FSpawnTabArgs& SpawnTabArgs)
{
	//Get Current Selection for displaying

	TArray<FAssetData> Items = CBGetSelectedItems();

	FName FirstItem;
	FText WidgetText;

	if (Items.IsValidIndex(0))	// Prüfen ob etwas ausgewählt out of bound crash
	{
		FirstItem = Items[0].ObjectPath;
	 WidgetText = FText::Format(
			LOCTEXT("WindowWidgetText", "Selected Item: {0}"),
			FText::FromString(FirstItem.ToString())
		);
	}
	else
	{
		WidgetText = FText::Format(
			LOCTEXT("WindowWidgetText", "Selected Item: {0}"),
			FText::FromString("None")
		);
	}


	// Window Layout -----------------------------------------------------------------

		return SNew(SDockTab)
			   .TabRole(ETabRole::NomadTab)
				[
					SNew(SScrollBox)
					+ SScrollBox::Slot().Padding(10, 5)
					[
						SNew(SVerticalBox)
						
						+ SVerticalBox::Slot().HAlign(HAlign_Center).VAlign(VAlign_Center)
							.MaxHeight(60.0f)
						[
							SNew(SButton)
							.VAlign(VAlign_Center)
							.HAlign(HAlign_Center)
							.Text(FText::FromString("Spawn Instances"))
							.ToolTipText(FText::FromString("Spawn Static Mesh"))
							.DesiredSizeScale(FVector2D(100.0f, 60.0f))
							.OnClicked_Raw(this, &FXSI2UE4Module::OnButtonClicked)
						]

						+ SVerticalBox::Slot().HAlign(HAlign_Center).VAlign(VAlign_Center)
							.MaxHeight(100.0f)
						[
								SNew(STextBlock)
								.Text(WidgetText)
						]
					]
				];
}

Selected assets function:

TArray<FAssetData> CBGetSelectedItems()
{
	TArray<FAssetData> AssetDatas;
	FContentBrowserModule& ContentBrowserModule = FModuleManager::LoadModuleChecked<FContentBrowserModule>("ContentBrowser");
	IContentBrowserSingleton& ContentBrowserSingleton = ContentBrowserModule.Get();
	ContentBrowserSingleton.GetSelectedAssets(AssetDatas);
	return AssetDatas;
}