My questions relates to this"Object reference not set to an instance of an object".

EDN Admin · Oct 22, 2012

Ive search around and I am trying to learn on my own. I know its good to ask around as well so here I go! After searching around, I am unable to find out the problems with my Windows Game coding in c#. When Debugging, the game beings. After scrolling
through the menu list and I click "Credits", I received this message. "Object reference not set to an instance of an object." Can you guess help me out? Thanks! 
 
**Credits Code**: 
 
 
namespace DoomSchneider_The_Game 
{ 
class Credits 
{ 
GraphicsDeviceManager graphics; 
SpriteBatch spriteBatch; 
 
Video creditsVid; 
VideoPlayer creditsPlayer; 
 
Texture2D creditsTexture; 
Rectangle creditsRectangle; 
 
 
public Credits() 
{ 
 
 
 
} 
 
public void Initialize() 
{ 
 
creditsPlayer = new VideoPlayer(); 
 
} 
 
public void LoadContent(ContentManager Content) 
{ 
 
creditsVid = Content.Load<Video>("Videos\Intro"); 
creditsRectangle = new Rectangle(0, 0, 100, 100); 
 
creditsPlayer.Play(creditsVid); 
 
} 
 
 
public void Update(GameTime gameTime) 
{ 
 
 
 
} 
 
 
public void Draw(SpriteBatch spriteBatch) 
{ 
 
creditsTexture = creditsPlayer.GetTexture(); 
 
spriteBatch.Begin(); 
spriteBatch.Draw(creditsTexture, creditsRectangle, Color.White); 
spriteBatch.End(); 
 
 
} 
 
} 
} 
 
 
 
 
 
**Menu Code:** 
 
 
namespace DoomSchneider_The_Game 
{ 
class MenuComponent 
{ 
KeyboardState keyboard; 
KeyboardState prevKeyboard; 
 
 
MouseState mouse; 
MouseState prevMouse; 
 
 
//Song 
Song menuSong; 
 
 
SpriteFont spriteFont; 
 
 
List<string> buttonList = new List<string>(); 
 
 
int selected = 0; 
 
 
public MenuComponent() 
{ 
buttonList.Add("Story"); 
buttonList.Add("Versus"); 
buttonList.Add("Online Play"); 
buttonList.Add("Extras"); 
buttonList.Add("Options"); 
buttonList.Add("Credits"); 
buttonList.Add("Exit"); 
 
} 
 
public void LoadContent(ContentManager Content) 
{ 
spriteFont = Content.Load<SpriteFont>("HUD"); 
 
//Song 
menuSong = Content.Load<Song>("Music\MainMenuMusic"); 
 
MediaPlayer.Play(menuSong); 
MediaPlayer.IsRepeating = true; 
} 
 
public void Update(GameTime gameTime) 
{ 
keyboard = Keyboard.GetState(); 
mouse = Mouse.GetState(); 
 
if (CheckKeyboard(Keys.Up)) 
{ 
if (selected > 0) selected--; 
} 
if (CheckKeyboard(Keys.Down)) 
{ 
if (selected < buttonList.Count - 1) selected++; 
} 
if (CheckKeyboard(Keys.Enter) || CheckKeyboard(Keys.Space) || CheckKeyboard(Keys.E)) 
{ 
switch (selected) 
{ 
case 0: 
Game1.GameState = "Story"; 
break; 
 
case 1: 
break; 
 
case 2: 
break; 
 
case 3: 
break; 
 
case 4: 
break; 
 
case 5: 
Game1.GameState = "Credits"; 
break; 
 
case 6: 
Game1.GameState = "Exit"; 
break; 
 
} 
} 
 
 
prevMouse = mouse; 
prevKeyboard = keyboard; 
} 
 
public bool CheckMouse() 
{ 
return (mouse.LeftButton ==ButtonState.Pressed && prevMouse.LeftButton == ButtonState.Released); 
} 
 
public bool CheckKeyboard(Keys key) 
{ 
return (keyboard.IsKeyDown(key) && !prevKeyboard.IsKeyDown(key)); 
} 
 
public void Draw(SpriteBatch spriteBatch) 
{ 
Color color; 
int linePadding = 3; 
 
spriteBatch.Begin(); 
for(int i = 0; i < buttonList.Count; i++) 
{ 
color = (i == selected) ? Color.DarkGoldenrod : Color.Black; 
spriteBatch.DrawString(spriteFont, buttonList, new Vector2((Game1.screen.Width/5) - (spriteFont.MeasureString(buttonList).X / 2), 
(Game1.screen.Height/2) - (spriteFont.LineSpacing * buttonList.Count/2) + ((spriteFont.LineSpacing + linePadding) * i)), color); 
 
} 
spriteBatch.End(); 
 
} 
 
} 
} 
 
 
 
 
 
**Game Code(Default generated class, if needed)** 
 
 
namespace DoomSchneider_The_Game 
{ 
/// <summary> 
/// This is the main type for your game 
/// </summary> 
public class Game1 : Microsoft.Xna.Framework.Game 
{ 
GraphicsDeviceManager graphics; 
SpriteBatch spriteBatch; 
 
//Menu Art 
Texture2D background; 
Rectangle backgroundRectangle; 
 
MenuComponent menucomponent; 
StoryMenuComponent storymenucomponent; 
Credits creditsClass; 
 
 
public static string GameState = "Menu"; 
 
public static Rectangle screen; 
 
public Game1() 
{ 
graphics = new GraphicsDeviceManager(this); 
Content.RootDirectory = "Content"; 
} 
 
/// <summary> 
/// Allows the game to perform any initialization it needs to before starting to run. 
/// This is where it can query for any required services and load any non-graphic 
/// related content. Calling base.Initialize will enumerate through any components 
/// and initialize them as well. 
/// </summary> 
protected override void Initialize() 
{ 
screen = new Rectangle(0, 0, graphics.PreferredBackBufferWidth, graphics.PreferredBackBufferHeight); 
 
menucomponent = new MenuComponent(); 
storymenucomponent = new StoryMenuComponent(); 
 
base.Initialize(); 
} 
 
/// <summary> 
/// LoadContent will be called once per game and is the place to load 
/// all of your content. 
/// </summary> 
protected override void LoadContent() 
{ 
// Create a new SpriteBatch, which can be used to draw textures. 
spriteBatch = new SpriteBatch(GraphicsDevice); 
 
//Menu Art 
background = Content.Load<Texture2D>("BackGrounds\MainMenuArt2"); 
backgroundRectangle = new Rectangle(GraphicsDevice.Viewport.X, GraphicsDevice.Viewport.Y, GraphicsDevice.Viewport.Width, GraphicsDevice.Viewport.Height); 
 
menucomponent.LoadContent(Content); 
storymenucomponent.LoadContent(Content); 
 
} 
 
/// <summary> 
/// UnloadContent will be called once per game and is the place to unload 
/// all content. 
/// </summary> 
protected override void UnloadContent() 
{ 
// TODO: Unload any non ContentManager content here 
} 
 
/// <summary> 
/// Allows the game to run logic such as updating the world, 
/// checking for collisions, gathering input, and playing audio. 
/// </summary> 
/// <param name="gameTime Provides a snapshot of timing values.</param> 
protected override void Update(GameTime gameTime) 
{ 
// Allows the game to exit 
if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed || GameState =="Exit") 
this.Exit(); 
 
switch (GameState) 
{ 
case "Menu": 
menucomponent.Update(gameTime); 
break; 
 
case "Story": 
storymenucomponent.Update(gameTime); 
break; 
 
case "Credits": 
creditsClass.Update(gameTime); 
break; 
} 
 
base.Update(gameTime); 
} 
 
/// <summary> 
/// This is called when the game should draw itself. 
/// </summary> 
/// <param name="gameTime Provides a snapshot of timing values.</param> 
protected override void Draw(GameTime gameTime) 
{ 
GraphicsDevice.Clear(Color.White); 
 
spriteBatch.Begin(); 
spriteBatch.Draw(background, backgroundRectangle, Color.White); 
spriteBatch.End(); 
 
switch (GameState) 
{ 
case "Menu": 
menucomponent.Draw(spriteBatch); 
break; 
case "Story": 
storymenucomponent.Draw(spriteBatch); 
break; 
} 
base.Draw(gameTime); 
} 
} 
} <hr class="sig AsianAvery

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My questions relates to this"Object reference not set to an instance of an object".

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