public void AddScreen(Screen screen)
{
screen.ScreenManager = this;
screen.IsExiting = false;
if (isInitialized)
{
screen.LoadContent();
}
screenToAdd = screen;
}
public void RemoveScreen(Screen screen)
{
if (isInitialized)
{
screen.UnloadContent();
}
screens.Remove(screen);
screensToUpdate.Remove(screen);
}
public override void Update(GameTime gameTime)
{
//Make a copy of all the screens
screensToUpdate.Clear();
foreach (Screen screen in screens)
{
screensToUpdate.Add(screen);
}
//If there is no screen then add the first one
if (screenToAdd != null && screensToUpdate.Count == 0)
{
screens.Add(screenToAdd);
screenToAdd = null;
}
//We assume the screen on top of the stack is active
bool shouldTransitionOff = false;
//If we have a screen waiting then the top screen should transition off
if (screenToAdd != null)
shouldTransitionOff = true;
if (screensToUpdate.Count > 0)
{
//Do logic for the top screen only
Screen topScreen = screensToUpdate[screensToUpdate.Count - 1];
screensToUpdate.RemoveAt(screensToUpdate.Count - 1);
topScreen.Update(gameTime, shouldTransitionOff);
//If the top screen has moved all the way off then add the next screen
if (topScreen.ScreenState == ScreenState.Hidden
&& screenToAdd != null)
{
screens.Add(screenToAdd);
screenToAdd = null;
}
//If the top screen has moved all the way off then remove the screen
//if (topScreen.ScreenState == ScreenState.Hidden
// && screenToRemove != null)
//{
// screens.Remove(screenToRemove);
// screenToRemove = null;
//}
//Handle input for the top screen if it is active
if (topScreen.ScreenState == ScreenState.Active
|| topScreen.ScreenState == ScreenState.TransitionOn)
{
topScreen.HandleInput(input);
shouldTransitionOff = true;
}
//We don't want to handle input if the screen is going away
if (topScreen.ScreenState == ScreenState.TransitionOff)
{
shouldTransitionOff = true;
}
}
//Loop through the rest of the screens
//while (screensToUpdate.Count > 0)
//{
// //take the top screen
// Screen screen = screensToUpdate[screensToUpdate.Count - 1];
// screensToUpdate.RemoveAt(screensToUpdate.Count-1);
// //Update it
// screen.Update(gameTime, shouldTransitionOff);
//}
#if DEBUG
List<string> screenNames = new List<string>();
foreach (Screen screen in screens)
screenNames.Add(screen.GetType().Name);
Debug.WriteLine(string.Join(", ", screenNames.ToArray()));
#endif
}