XNA 4.0 Game Development by Example Beginner's Guide（Visual Basic Edition）

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Time for action – drawing the screen – the title screen

Modify the Draw() method of Game1 to include the code necessary to draw the game's title screen after GraphicsDevice.Clear(Color.CornflowerBlue):

If gameState = GameStates.TitleScreen Then
  spriteBatch.Begin()
  spriteBatch.Draw(titleScreen,New Rectangle(0, 0,Me.Window.ClientBounds.Width,Me.Window.ClientBounds.Height),
    Color.White)
  spriteBatch.End()
End If

Run the game and verify that the title screen is displayed. You will not be able to start the game yet, however, as we have not written the Update() method yet.
Stop the game by pressing Alt + F4.

What just happened?

The title screen is drawn with a single call to the Draw() method of the spriteBatch object. Since the title screen will cover the entire display, a rectangle is created that is equal to the width and height of the game window.

The Draw() method – the play screen

Finally, we are ready to display the playing pieces on the screen. We will accomplish this by using a simple loop to display all of the playing pieces in the _gameBoard object.