C# ArgumentNullException 未处理 (SpriteBatch.Draw)
C# ArgumentNullException was unhandled (SpriteBatch.Draw)
我实际上是 XNA 的新学生,发现这个库非常有趣,但我仍然缺乏一些知识来进一步学习,因为我觉得我无法自己解决 :(
spriteBatch.Draw() 方法说我的纹理是空的,但是我已经将它加载到 Resources.cs class 中并在 MainMenu.cs 中传递了纹理,所以我真的不知道问题出在哪里,如果有人能帮助我,我将非常感激!
Resources.cs
class Resources
{
public static Texture2D pixel;
public static Texture2D startButton, loadButton, quitButton;
public static SpriteFont consoleFont;
public static void LoadContent(ContentManager Content)
{
pixel = Content.Load<Texture2D>("Pixel");
consoleFont = Content.Load<SpriteFont>("Console");
// UI Ressources :
startButton = Content.Load<Texture2D>("UI/StartButton");
loadButton = Content.Load<Texture2D>("UI/LoadButton");
quitButton = Content.Load<Texture2D>("UI/QuitButton");
}
}
MainMenu.cs
class MainMenu
{
// Fields
List<Button> buttons = new List<Button>();
// Constructors
public MainMenu()
{
this.buttons.Add(new Button(new Vector2(480, 132), 256, 48, Resources.startButton));
this.buttons.Add(new Button(new Vector2(480, 212), 256, 48, Resources.loadButton));
this.buttons.Add(new Button(new Vector2(480, 292), 256, 48, Resources.quitButton));
}
// Methods
// Update
public void Update()
{
}
// Draw
public void Draw(SpriteBatch spriteBatch)
{
foreach (Button button in buttons)
{
button.Draw(spriteBatch);
}
}
}
Button.cs
class Button : UIElement
{
int width, height;
Texture2D texture;
public Button()
{
}
public Button(Vector2 b_position, int b_width, int b_height, Texture2D b_texture)
{
this.position = b_position;
this.width = b_width;
this.height = b_height;
this.texture = b_texture;
}
public void Update()
{
}
public void Draw(SpriteBatch spriteBatch)
{
spriteBatch.Draw(texture, position, Color.White);
}
}
虽然我没有看到您的游戏 class,但我的第一个假设是您从不在资源 class 中调用 public static void LoadContent(ContentManager Content) 方法。由于此函数正在实例化您的纹理,因此可能未调用它。
感谢您的回复!
的确,我忘了包含游戏 class,这是调用资源的正确方法吗?
public class GameMain : Microsoft.Xna.Framework.Game
{
GraphicsDeviceManager graphics;
SpriteBatch spriteBatch;
MainMenu mainMenu;
public GameMain()
{
graphics = new GraphicsDeviceManager(this);
Content.RootDirectory = "Content";
this.IsMouseVisible = true;
mainMenu = new MainMenu();
}
protected override void Initialize()
{
// TODO: Add your initialization logic here
base.Initialize();
}
protected override void LoadContent()
{
// Create a new SpriteBatch, which can be used to draw textures.
spriteBatch = new SpriteBatch(GraphicsDevice);
// TODO: use this.Content to load your game content here
Resources.LoadContent(Content);
}
protected override void UnloadContent()
{
// TODO: Unload any non ContentManager content here
}
protected override void Update(GameTime gameTime)
{
// Allows the game to exit
if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
this.Exit();
// TODO: Add your update logic here
base.Update(gameTime);
}
protected override void Draw(GameTime gameTime)
{
GraphicsDevice.Clear(Color.CornflowerBlue);
// TODO: Add your drawing code here
spriteBatch.Begin();
mainMenu.Draw(spriteBatch);
spriteBatch.End();
base.Draw(gameTime);
}
}
简单真实
你只要知道Game1
的函数调用顺序就行了。首先,调用 Game1 的构造函数。那就是你放置 mainMenu = new MainMenu();
的地方。之后去 Initialize
、Load
等等。您必须将 mainMenu = new MainMenu();
从 Game1 构造函数移动到 Load
函数,在 Resources.LoadContent(Content);
之后,以便可以在 MainMenu
中使用资源之前加载它们。您的 Game1.cs
代码应如下所示:
public class GameMain : Microsoft.Xna.Framework.Game
{
GraphicsDeviceManager graphics;
SpriteBatch spriteBatch;
MainMenu mainMenu;
public GameMain()
{
graphics = new GraphicsDeviceManager(this);
Content.RootDirectory = "Content";
this.IsMouseVisible = true;
}
protected override void Initialize()
{
// TODO: Add your initialization logic here
base.Initialize();
}
protected override void LoadContent()
{
// Create a new SpriteBatch, which can be used to draw textures.
spriteBatch = new SpriteBatch(GraphicsDevice);
// TODO: use this.Content to load your game content here
Resources.LoadContent(Content);
mainMenu = new MainMenu();
}
protected override void UnloadContent()
{
// TODO: Unload any non ContentManager content here
}
protected override void Update(GameTime gameTime)
{
// Allows the game to exit
if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
this.Exit();
// TODO: Add your update logic here
base.Update(gameTime);
}
protected override void Draw(GameTime gameTime)
{
GraphicsDevice.Clear(Color.CornflowerBlue);
// TODO: Add your drawing code here
spriteBatch.Begin();
mainMenu.Draw(spriteBatch);
spriteBatch.End();
base.Draw(gameTime);
}
}
我实际上是 XNA 的新学生,发现这个库非常有趣,但我仍然缺乏一些知识来进一步学习,因为我觉得我无法自己解决 :(
spriteBatch.Draw() 方法说我的纹理是空的,但是我已经将它加载到 Resources.cs class 中并在 MainMenu.cs 中传递了纹理,所以我真的不知道问题出在哪里,如果有人能帮助我,我将非常感激!
Resources.cs
class Resources
{
public static Texture2D pixel;
public static Texture2D startButton, loadButton, quitButton;
public static SpriteFont consoleFont;
public static void LoadContent(ContentManager Content)
{
pixel = Content.Load<Texture2D>("Pixel");
consoleFont = Content.Load<SpriteFont>("Console");
// UI Ressources :
startButton = Content.Load<Texture2D>("UI/StartButton");
loadButton = Content.Load<Texture2D>("UI/LoadButton");
quitButton = Content.Load<Texture2D>("UI/QuitButton");
}
}
MainMenu.cs
class MainMenu
{
// Fields
List<Button> buttons = new List<Button>();
// Constructors
public MainMenu()
{
this.buttons.Add(new Button(new Vector2(480, 132), 256, 48, Resources.startButton));
this.buttons.Add(new Button(new Vector2(480, 212), 256, 48, Resources.loadButton));
this.buttons.Add(new Button(new Vector2(480, 292), 256, 48, Resources.quitButton));
}
// Methods
// Update
public void Update()
{
}
// Draw
public void Draw(SpriteBatch spriteBatch)
{
foreach (Button button in buttons)
{
button.Draw(spriteBatch);
}
}
}
Button.cs
class Button : UIElement
{
int width, height;
Texture2D texture;
public Button()
{
}
public Button(Vector2 b_position, int b_width, int b_height, Texture2D b_texture)
{
this.position = b_position;
this.width = b_width;
this.height = b_height;
this.texture = b_texture;
}
public void Update()
{
}
public void Draw(SpriteBatch spriteBatch)
{
spriteBatch.Draw(texture, position, Color.White);
}
}
虽然我没有看到您的游戏 class,但我的第一个假设是您从不在资源 class 中调用 public static void LoadContent(ContentManager Content) 方法。由于此函数正在实例化您的纹理,因此可能未调用它。
感谢您的回复! 的确,我忘了包含游戏 class,这是调用资源的正确方法吗?
public class GameMain : Microsoft.Xna.Framework.Game
{
GraphicsDeviceManager graphics;
SpriteBatch spriteBatch;
MainMenu mainMenu;
public GameMain()
{
graphics = new GraphicsDeviceManager(this);
Content.RootDirectory = "Content";
this.IsMouseVisible = true;
mainMenu = new MainMenu();
}
protected override void Initialize()
{
// TODO: Add your initialization logic here
base.Initialize();
}
protected override void LoadContent()
{
// Create a new SpriteBatch, which can be used to draw textures.
spriteBatch = new SpriteBatch(GraphicsDevice);
// TODO: use this.Content to load your game content here
Resources.LoadContent(Content);
}
protected override void UnloadContent()
{
// TODO: Unload any non ContentManager content here
}
protected override void Update(GameTime gameTime)
{
// Allows the game to exit
if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
this.Exit();
// TODO: Add your update logic here
base.Update(gameTime);
}
protected override void Draw(GameTime gameTime)
{
GraphicsDevice.Clear(Color.CornflowerBlue);
// TODO: Add your drawing code here
spriteBatch.Begin();
mainMenu.Draw(spriteBatch);
spriteBatch.End();
base.Draw(gameTime);
}
}
简单真实
你只要知道Game1
的函数调用顺序就行了。首先,调用 Game1 的构造函数。那就是你放置 mainMenu = new MainMenu();
的地方。之后去 Initialize
、Load
等等。您必须将 mainMenu = new MainMenu();
从 Game1 构造函数移动到 Load
函数,在 Resources.LoadContent(Content);
之后,以便可以在 MainMenu
中使用资源之前加载它们。您的 Game1.cs
代码应如下所示:
public class GameMain : Microsoft.Xna.Framework.Game
{
GraphicsDeviceManager graphics;
SpriteBatch spriteBatch;
MainMenu mainMenu;
public GameMain()
{
graphics = new GraphicsDeviceManager(this);
Content.RootDirectory = "Content";
this.IsMouseVisible = true;
}
protected override void Initialize()
{
// TODO: Add your initialization logic here
base.Initialize();
}
protected override void LoadContent()
{
// Create a new SpriteBatch, which can be used to draw textures.
spriteBatch = new SpriteBatch(GraphicsDevice);
// TODO: use this.Content to load your game content here
Resources.LoadContent(Content);
mainMenu = new MainMenu();
}
protected override void UnloadContent()
{
// TODO: Unload any non ContentManager content here
}
protected override void Update(GameTime gameTime)
{
// Allows the game to exit
if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
this.Exit();
// TODO: Add your update logic here
base.Update(gameTime);
}
protected override void Draw(GameTime gameTime)
{
GraphicsDevice.Clear(Color.CornflowerBlue);
// TODO: Add your drawing code here
spriteBatch.Begin();
mainMenu.Draw(spriteBatch);
spriteBatch.End();
base.Draw(gameTime);
}
}