More of a text snippet than a tutorial, this is how it's possible to call a function when the game loses focus.
In this example we have put the callback function in a custom
APlayerController subclass, but it could be just about anywhere.
Also it might be worth wrapping this feature in a UUserGameSetting property
so players can disable it if they don't want it.
void ABUIPlayerController::BeginPlay()
{
FSlateApplication::Get().OnApplicationActivationStateChanged()
.AddUObject( this, &ABUIPlayerController::OnWindowFocusChanged );
}
void ABUIPlayerController::OnWindowFocusChanged( bool bIsFocused )
{
// Don't pause in the editor, it's annoying
#if !WITH_EDITOR
if ( bIsFocused )
{
// Unlimit game FPS
GEngine->SetMaxFPS( 0 );
// Unpause the game
// MyHUD->SetPause( false );
}
else
{
// Reduce FPS to max 10 while in the background
GEngine->SetMaxFPS( 10.0f );
// Pause the game, using your "show pause menu" function
// MyHUD->SetPause( true );
}
#endif
}
