source: 2011/23/sijoseha/Fera Proelia/Fera Proelia/Fera Proelia/GameScreen.cs @ 2144

using System;
using System.Collections.Generic;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input.Touch;

namespace Fera_Proelia
{
    public enum ScreenState
    {
        Active,
        Hidden,
    }
    public abstract class GameScreen
    {
        public bool IsActive
        {
            get { return !otherScreenHasFocus && screenState == ScreenState.Active; }
        }
        bool otherScreenHasFocus;

        public bool IsExiting
        {
            get { return isExiting; }
            protected internal set { isExiting = value; }
        }

        bool isExiting = false;

        public ScreenManager ScreenManager
        {
            get { return screenManager; }
            internal set { screenManager = value; }
        }
        ScreenManager screenManager;

        public ScreenState ScreenState
        {
            get { return screenState; }
            protected set { screenState = value; }
        }

        ScreenState screenState = ScreenState.Hidden;

        public GestureType EnabledGestures
        {
            get { return enabledGestures; }
            protected set
            {
                enabledGestures = value;
            }
        }
        GestureType enabledGestures = GestureType.None;

        public GameScreen()
        {

        }
        public virtual void LoadContent() { }
        public virtual void UnloadContent() { }

        public virtual void Update(GameTime gameTime, bool otherScreenHasFocus, bool coveredByOtherScreen)
        {
            this.otherScreenHasFocus = otherScreenHasFocus;
            if (isExiting)
            {
                ScreenManager.RemoveScreen(this);
            }
            else if (coveredByOtherScreen)
            {
                screenState = ScreenState.Hidden;
            }
            else
            {
                screenState = ScreenState.Active;
            }
        }

        public virtual void HandleInput(InputState input) { }

        public virtual void Draw(GameTime gameTime) { }

        public void ExitScreen()
        {
            ScreenManager.RemoveScreen(this);
        }
    }
}