Errata

The text in the last paragraph before the "there are no Dumb Questions" section does not match what is being discussed directly above and the code snippet uses as an example. As there is no "ScoreText.text" within the snippet or an attempt to assign 'x' to it.

This can be found in Chapter 4 page 205 of the .pdf file. It is the same in my Kindle eBook version on page 520 (page may differ slightly based on font size on Kindle).

I would copy and paste the exact text involved, but there is an image (Error Exception message) within the text that interferes.

Note from the Author or Editor:
Thanks for catching this – looks like this was a (ScoreText.text is from a Unity lab later in the book). This paragraph should be updated to read:

text is a string variable, so when you used the + operator to concatenate a string it converted the value to a string and the assignment worked. But when you try to assign the number value to it directly, it doesn’t have a way to automatically convert the long value to a string. You can convert a numeric value (or any other value!) to a string by calling its ToString method.

Microsoft released .NET 9.0 after the first printing. The following changes bring the book up to date with .NET 9.0 (all images are updated in Subversion):

Page 7
In step 4, change both occurrences of 8.0 to 9.0 in this sentence:
The current version of .NET at the time we’re writing this is 8.0—make sure the version that
you’re using is 8.0 (or higher).

Replace the first image in Step 4 with Links/ch01_screenshots/ch01_screenshot_vs_windows_9_NEW.psd

Page 8
Change net8.0 to net9.0 in the command output in the middle of the page

Replace the screenshot in Step 6 with Links/ch01_screenshots/ch01_screenshot_vs_windows_12_NEW.psd

Page 24
In annotation change .NET 8 to .NET 9

Update first image to Links/ch01_screenshots/ch01_screenshot_vs_mac_9_NEW.psd

Update second image to
Links/ch01_screenshots/ch01_screenshot_vs_windows_15_NEW.psd

Page 25
Update the image of the phone to Links/ch01_screenshots/ch01_screenshot_vs_android_1_NEW.psd

Page 88
Update image of robot in the race car to the .NET 9 image of a robot in a drone
Replace the first image with Links/dotnet_bot_9.0.png

Fix the button image
Replace the third image with Links/ch02_screenshots/ch02_new_screenshot_46_NEW.psd
(resize so it looks okay)

Page 91
Change "cute robot driving a race car" to "cute robot"

Replace top image with Links/ch02_screenshots/ch02_new_screenshot_1_NEW.psd

Page 96
Replace screenshot image at the bottom of the page with Links/ch02_screenshots/ch02_new_screenshot_19_NEW.psd
In text in lower left change .NET 8 to .NET 9

Page 460
In the first line, change "robot driving the race car" to "cute robot"

Page 626
In "Check the bin\Debug\net8.0 folder underneath your Solution folder" change net8.0 to net9.0

Page 668
Change paths to net9.0 in the following commands:
cd HexDumper/bin/Debug/net8.0
cd WriteArgs/bin/Debug/net8.0

Change the top annotation to: "This book uses .NET 9.0—if you’re using this with a different version, replace net9.0 with the matching version."

Page 738
There are five occurrences of net8.0 that need to be changed to net9.0
- Three are in the first three lines of command output at the top
- One in the second bullet below
- One in the third bullet below

Page 740
In command line in middle of the page that starts C:\Users\Public\source...
Change both occurrences of net8.0 to net9.0

Page 759
Bottom of page - in this text "You can see the DLL files by building your app and then
opening the bin\Debug\net8.0 folder"
Change net8.0 to net9.0

Unity 6 was released after the first printing of the book. This is a cumulative update to bring the book up to date with Unity 6 (all images are updated in Subversion):

Page xxxvii:
In paragraph 3, change boldfaced text Unity 2023.2 to Unity 6



Page 113:

1. Delete the ellipse

2. Replace the first image with Links/ch02_unity_lab_1_screenshots/ch01_unity_screenshots_3_NEW.psd

3. Delete the second image on the page

4. Move the arrow up and to the left so it points to the "Install Editor" button

5. Replace the text in the caption box with the following (resize the box smaller so it fits the text):

Unity Hub helps you manage your Unity installs and projects. We used screenshots from Unity 6 in these Unity Labs, because that was the most recent version available when we went to production. You should install the latest official release. When you click the Install Editor button, Unity Hub will display a list of official releases. Install the most recent version of Unity 6. Make sure you choose the version (x64 or Arm64) that matches your hardware.

6. In the paragraph below, replace this text:
install the latest official release that starts with Unity 2023

With this text ("Unity 6" is in boldface):
install the version of Unity 6 that matches your hardware (x64 or Arm64)

7. In the "Watch It!" box, replace this text:
The screenshots in this book were taken with Unity 2023.2 in dark mode and Unity Hub 3.7.0 in light mode.

With this text ("Unity 6" and "Unity Hub 3.10.0" are in boldface):
The screenshots in this book were taken with Unity 6 and Unity Hub 3.10.0.

8. Delete this sentence and resize the "Watch It!" box (you may want to adjust its position to balance the whitespace on the page): "The next version, Unity 6, is in early release as we go to print. Watch for PDFs of updated labs on our GitHub page: https_//github.com/head-first-csharp/fifth-edition"

9. Delete this annotation and its accompanying arrow: "At the time we’re writing this, Unity is planning on moving away from year-based versions and calling their next version Unity 6."


Page 114:

Change the text "make sure the 3D template is selected" to "select the Universal 3D template" ("Universal 3D" is in boldface)

Replace the top three images with Links/ch02_unity_lab_1_screenshots/ch01_unity_screenshots_11_NEW.psd (they are al linked to the same file)

Replace the bottom image with Links/ch02_unity_lab_1_screenshots/ch01_unity_screenshots_7_NEW.psd
Resize the image frame so it fits the image

Move the annotation that starts "You’ll use the Scene window" up so it's centered in the gray area and doesn't overlap any darker areas of the image.

Move the annotation that starts "Every object" up to make room.

Move the annotation that starts "Use the Project window" to the right so it's in the Inspector window. Add an arrow that points from that annotation to the Project window.


Page 119:

The text block that starts "You can learn more about..." should be in a caption box, one of those boxes with rounded corners. Set its border to 1 pt black, and give it 0p3 rounded corners.



Page 120:

Replace the top image with Links/ch02_unity_lab_1_screenshots/ch01_unity_screenshots_28_NEW.psd


Page 121:

Replace the top image with Links/ch02_unity_lab_1_screenshots/ch01_unity_screenshots_29_NEW.psd

In Step 5, replace "drag it onto your sphere" with "drag it into the Hierarchy window onto the Sphere that you added" in boldface

Replace the third image in Step 5 (the one that's a picture of a light sphere on a dark gray background) with Links/ch02_unity_lab_1_screenshots/ch01_unity_screenshots_31_NEW.psd

Replace the bottom image with Links/ch02_unity_lab_1_screenshots/ch01_unity_screenshots_34_NEW.psd


Page 122:

Replace the screenshot with Links/ch02_unity_lab_1_screenshots/unity_version_control_window_NEW.psd

Replace the small icon image in the top line in the box to the right of the screenshot with Links/ch02_unity_lab_1_screenshots/

Page 123:

In the "Relax" box change this text: and move the Scene view
To this: and the Scene view.


Page 125:

Replace the image with Links/ch02_unity_lab_1_screenshots/ch01_unity_screenshots_41_NEW.psd

Move the arrow at the top to the left so it points down at the question mark icon in the image

The new image is shorter than the old one, so move the arrow and annotation at the bottom of the page up to close the gap


Page 258:

Replace the top image with Links/ch04_unity_lab_2_screenshots/ch02_unity_screenshots_36_NEW.psd

Remove the annotation overlapping the image that starts "If you used Unity Version Control to upload" along with its arrow


Page 260:

Remove these two lines of code from the top of the block of code:

using System.Collections;
using System.Collections.Generic;

The annotation and arrow will overlap the code after that change, so you'll need to widen the caption box ("You opened your C# script in...") to make room so you can move the annotation and arrow up.

You can resize the screenshot so it's a little bigger. Make sure the right arrow from the box that says "Your game will start..." points to the 8 ball, and the left arrow from the box that says "Click on Sphere in the..." points to the Hierarchy tab.

Move the screenshot up as well. The arrows don't line up correctly -- make sure the


Page 261:

Remove these two lines of code from the top of the code:

using System.Collections;
using System.Collections.Generic;

You can replace them with blank lines so they don't mess up the spacing of the rest of the page.


Page 404:

Replace the image at the bottom of the page with Links/ch06_unity_lab_3_screenshots/ch03_unity_screenshots_30_NEW.psd

The image is inside a text frame, so you'll need to expand the text frame vertically before you can expand the image frame downwards to show the entire image.


Page 405:

Replace the top image with Links/ch06_unity_lab_3_screenshots/ch03_unity_screenshots_3_NEW.psd

Replace the second image with
Links/ch06_unity_lab_3_screenshots/ch03_unity_screenshots_4_NEW.psd

Move the circle so it is over the square to the left of the label "Base Map" and then move the arrow so it starts in the middle of the 1 Ball Texture icon (between the two 1's) and points to the circle. This is supposed to indicate that the user will drag the 1 Ball Texture icon onto the Base Map box.

Replace the third image with Replace the second image with
Links/ch06_unity_lab_3_screenshots/ch03_unity_screenshots_5_NEW.psd

Resize and move the circle over that image so it is around the square to the left of the "Base Map" icon, which now looks like the 1 Ball Map icon.

In the "Behind the Scenes" box, replace this sentence:
and the albedo controls the color of that surface. “Albedo” is a term from physics (specifically astronomy)

With this (albedo is in boldface):
and the base map controls its albedo. "Albedo" is a game development term borrowed from physics

Add the following annotation in the space to the left of the 'Behind the Scenes" box with an arrow pointing to the box:
Previous versions of Unity used the term Albedo instead of Base Map, so you’ll see that term a lot in search results.


Page 409:
Replace this sentence:
Right-click on the Scripts folder in the Project window and create a new script called GameController.

With this ("Create a new script" is in boldface and "Create >> Scripting >> MonoBehavior Script" is in italics):
Create a new script called GameController. Right-click on the Scripts folder and choose Create >> Scripting >> MonoBehavior Script.


Page 413:
Replace the third screenshot (Rigidbody) with Links/ch06_unity_lab_3_screenshots/ch03_unity_screenshots_22_NEW.psd


Page 550:

Remove these two lines from the top of the code:

using System.Collections;
using System.Collections.Generic;

The Exercise box wraps to page 551, so make the box on 550 smaller so "void ResetBall()" is still at the top of the box on page 551.


Page 674:

Change this text:
right of the word “Albedo” in the Inspector

To this:
right of the word “Base Map” in the Inspector

Replace the "Main Maps" screenshot under the third paragraph with ch05_unity_screenshots_6_NEW.psd


Page 676:

Replace the two side by side screenshots under the third paragraph.

Replace the left one with Links/ch10_unity_lab_5_screenshots/ch05_unity_screenshots_11_NEW.psd

Replace the right one with Links/ch10_unity_lab_5_screenshots/ch05_unity_screenshots_10_NEW.psd


Page 678:

Change the boldfaced text in the first sentence from this:
install the AI Navigation package, which installs

to this ("AI Navigation package" is in boldface):
make sure the AI Navigation package is installed, which provides

Change step 4 to ("Install button" is in boldface):

Make sure that there's a checkmark with a circle next to AI Navigation. If it isn't, click the Install button to install it.


In the top right caption box, change this text:
Once you’ve selected the AI Navigation package, click the Install button to install it.

to this (you'll need to make the box a little bigger, Install button is in gray italics):

If the AI Navigation package isn't already installed, select it and click the Install button to install it.


Page 680:

Change all four occurrences of NavMeshSurface to NavMesh Surface


Pages 684:

The Sharpen Your Pencil exercise on this page needed significant updates. The updated page can be found in the InDesign file in Subversion: hfc#5e_ch10_unity_lab_5_pages_684_686_updates


Page 686:

The Sharpen Your Pencil solution on this page needed significant updates, and two bullet points were added. The updated page can be found in the InDesign file in Subversion: hfc#5e_ch10_unity_lab_5_pages_684_686_updates


Page 765:

Replace the screenshot in the lower right with Links/ch12_unity_lab_6_screenshots/ch06_unity_screenshots_5_NEW.psd


Page 766:

Replace the first screenshot with Links/ch12_unity_lab_6_screenshots/ch06_unity_screenshots_13_NEW.psd

Replace the second screenshot with Links/ch12_unity_lab_6_screenshots/ch06_unity_screenshots_11_NEW.psd

There is no “Margin” property in the Properties window. Had to type Margin="0,0,0,20" into the tag by hand.

Note from the Author or Editor:
Add a warning to the top of the page formatted similar to the on at the top of page 30 (you can remove the line break between the first two paragraphs to make room):

An update to Visual Studio since we took that screenshot may have removed Margin from the Properties window. If you don't see it (or any other property), just type the XAML so it matches.

Updating this page to include updates to Visual Studio Code since the first printing.

1. Replace the top screenshot with Links/ch01_screenshots/vscode_new_maui_project.psd_NEW.png (updated in Subversion) -- VSCode included a cosmetic change

2. Delete the "Name the new project" screenshot and move everything under it up to make room at the bottom of the page

3. Add the following text to the space created at the bottom of the page (the words "Debug project associated with this file" are in boldface):

There’s another way to run your MAUI app. Choose Debug project associated with this file from the dropdown next to the Run button at the upper right corner of the VSCode window.

4. Add the graphic Links/ch01_screenshots/vscode_debug_project_dropdown.png next to the text from #3. This shows a screenshot of the dropdown.

I created a folder "hfc#5e_ch01_page_23_update" in Subversion with an InDesign page that has all of these changes, you can copy the entire page from the file in that folder.

Visual Studio Code's features to work with XAML in .NET MAUI apps have improved significantly since the first printing. The "Watch It!" box should be updated. I've indicated what should be bold using <bold>...</bold>.

<bold>You can always edit your XAML by hand instead of using the Toolbox or Properties windows.</bold>

When you use Visual Studio Code to edit the XAML code in MainPage.xaml, you may notice that it's missing some of the features we show in Visual Studio. At the time we're writing this, VSCode's .NET MAUI editor doesn't have a Toolbox or a Properties window.

Even if you're using Visual Studio, you might find that an element you need isn't in the Toolbox, or a property isn't in the Properties window. That's okay—the only thing those windows do is <bold>add or change tags in your XAML code</bold>. You get exactly the same XAML code whether you type it in or use the IDE's build-in tools.

In fact, it's often faster to edit your XAML by hand than to search the Toolbox or Properties windows. So even if we tell you to use the Toolbox or Properties window, <bold>you can always type in the XAML code instead</bold>.

Thanks to updates in Visual Studio Code since the first printing, the warning in the middle of the page is no longer correct—VSCode now has the <New Event Handler> pop-up.

The warning should be changed to this:

If you use IntelliSense to complete your line, it may not add the C# code—you'll need to open MainPage.xaml.cs and add this code to by hand. Your app will still work just fine.

Add the a caption box (one of those boxes with rounded corners) to the bottom of the page with the following text – you can move the "Sharpen your pencil solution" box up to make room:

Do you see a warning in the Error List window about a non-nullable field? Your code will still run even when you see green warnings (unlike errors red errors, which mean your code can't run). But you should still pay attention to warnings! Don't worry about this warning for now—you'll learn about what it is and how to fix it in Chapter 11.

The keyword "static" is unnecessary and should be removed.

Note from the Author or Editor:
Remove the word "static" from these lines:

static void TryAnIf()

static void TryAnIfElse()

static void TrySomeLoops()

Add a caption box that says:

If an “AI Navigation” box is making it hard to see what’s going on, right-click on its header and choose Hide.

This needs checking but the question at the top of the page:

'Remember the sealed modifier from Chapter 7? It’s how you set up a class that can’t be extended.'

Refers to the sealed modifier from chapter 7, but I don't think the sealed modifier had been mentioned by that point. I may be mistaken though.

Note from the Author or Editor:
This is correct. Make the following changes.

Page 699:

Remove the annotation "Structs can implement interfaces but can't subclass other classes. And structs are sealed so they can't be extended."

Replace it with a caption box (one of those boxes with rounded corners) with the following text:

Structs can implement interfaces but can't subclass other classes. And structs are sealed so they can't be extended. You can make any class sealed by adding the sealed access modifier to it.

Add Access modifiers, sealed to the index


Page 723:
Change this annotation: "Remember the sealed modifier from chapter 7? It's how you set up a class that can't be extended."

To this: "We talked about earlier in the chapter about how structs are sealed, and how you can use the sealed access modifier to make a class that can't be extended."