TSharedRef<SWidget> UUserWidget::MakeViewportWidget(TSharedPtr<SWidget>& UserSlateWidget)
{
UserSlateWidget = TakeWidget();
return SNew(SConstraintCanvas)
+ SConstraintCanvas::Slot()
.Offset(BIND_UOBJECT_ATTRIBUTE(FMargin, GetFullScreenOffset))
.Anchors(BIND_UOBJECT_ATTRIBUTE(FAnchors, GetViewportAnchors))
.Alignment(BIND_UOBJECT_ATTRIBUTE(FVector2D, GetFullScreenAlignment))
[
UserSlateWidget.ToSharedRef()
];
}
void UUserWidget::AddToScreen(ULocalPlayer* Player, int32 ZOrder)
{
if ( !FullScreenWidget.IsValid() )
{
// First create and initialize the variable so that users calling this function twice don't
// attempt to add the widget to the viewport again.
TSharedRef<SConstraintCanvas> FullScreenCanvas = SNew(SConstraintCanvas);
FullScreenWidget = FullScreenCanvas;
TSharedRef<SWidget> UserSlateWidget = TakeWidget();
FullScreenCanvas->AddSlot()
.Offset(BIND_UOBJECT_ATTRIBUTE(FMargin, GetFullScreenOffset))
.Anchors(BIND_UOBJECT_ATTRIBUTE(FAnchors, GetViewportAnchors))
.Alignment(BIND_UOBJECT_ATTRIBUTE(FVector2D, GetFullScreenAlignment))
[
UserSlateWidget
];
// If this is a game world add the widget to the current worlds viewport.
UWorld* World = GetWorld();
if ( World && World->IsGameWorld() )
{
if ( UGameViewportClient* ViewportClient = World->GetGameViewport() )
{
if ( Player )
{
ViewportClient->AddViewportWidgetForPlayer(Player, FullScreenCanvas, ZOrder);
}
else
{
// We add 10 to the zorder when adding to the viewport to avoid
// displaying below any built-in controls, like the virtual joysticks on mobile builds.
ViewportClient->AddViewportWidgetContent(FullScreenCanvas, ZOrder + 10);
}
// Just in case we already hooked this delegate, remove the handler.
FWorldDelegates::LevelRemovedFromWorld.RemoveAll(this);
// Widgets added to the viewport are automatically removed if the persistent level is unloaded.
FWorldDelegates::LevelRemovedFromWorld.AddUObject(this, &UUserWidget::OnLevelRemovedFromWorld);
}
}
}
else
{
FMessageLog("PIE").Warning(FText::Format(LOCTEXT("WidgetAlreadyOnScreen", "The widget '{0}' was already added to the screen."),
FText::FromString(GetClass()->GetName())));
}
}
