Errata

The code as written in the book:

keyArray = [myDict allKeys];
for (index = 0; index < [keyArray count]; index++)
NSLog(@"Dictionary key at index %i is %@.
", index,
[keyArray objectAtIndex: index]);

Earlier in the code I have keyArray typed as:

NSMutableArray *keyArray;

and allocated and initialized as:

keyArray = [[NSMutableArray alloc] init];

When I build the project, I get the following warning:

assignment from incompatible pointer type

this applies to the line:

keyArray = [myDict allKeys];

When I run the program, I get the proper results, but get the following when
terminating:

Hello World has exited due to signal 11 (SIGSEGV).

Have I done something wrong, or is there a problem or omission in the book.
(I have found that the book assumes you know how and where to type and
initialize new variables. For a beginner this is a challenge.)

In the block of literal text to be entered for the bullet item "Add several different
key-value pairs to the dictionary..." the word "index" is used as the loop variable
everywhere but within the "NSLog" statement , where it is referenced as "i" (look for
"%i")

The NSObject is only available when the application is a Cocoa Java application, not a plain Cocoa application. Without further exp
loration this renders the rest of the chapter unusable.

Proj builder 1.0.1 build ver 63 I cannot drag the MyController instance to
the text field nothing happens.Figure 6-14 page 74
is incorrect. Same for page 87 figure 6-26.

I consider my self a compotent Unix programmer but this ones
got me beat please help.

There does not appear to be any support for Project Indexing in Project Builder 1.1.1
(December 2001 release) in the manner described in this section (Command-Option-I or
via Project Menu). Unable to continue in this section of the book.

Project Builder 1.1.1 automatically indexes projects with out any intervention of the
user. This feature can be turned off in the Info window after selecting the
project in "Groups and Files" on "Files" tab of P.B. You can also rebuild the index
at anytime if you suspect corruption. See Project Builder Help for more info.

Code snipet;
convertAmount is declared as an instance method. However the Converter class does not
have constructor, so could convertAmount be used as an instance method?

In the following page (122), convertAmout is used with the instance "convert", but
its not declared.

To make it work:
1. Should'nt convertAmount be delcared as a class method?

+ (float) convertAmount: (float) amt atRate: (float) rate;

2. Should be used as:

total = [Converter convertAmount: amout atRate : rate];

I believe that:

- (id) awakeFromNib

should be:

- (void) awakeFromNib

Step 4 requires the student to "Open My Data Source.m and import Expense.h," but
this indicates that this text is added to My Data Source.m when in fact it
should be added to My Data Source.h.

as printed, the line reads:
(NSDecimalNumber *) [NSDecimalNumber numberWithInt:index]];
The completed examples downloaded from this site read ( for the same line):
[NSDecimalNumber numberWithInt:index]];

This doesn't seem necessary.

The unsuitable last three lines will select the current day (Today) quite independent of any other selections that may be current. With the published code, in the current month, both the 1st and the current day will be selected after some juggling between the months.
The solution is to replace these lines with the much simpler code used in the refreshCalendar method that will automatically select a new cell and deselect any other selection.

[self selectCellWithTag:([now dayOfMonth] + startOffset - 1)];

The line [self highlightTodayIfVisible]; should be removed as it prevents the selection of other dates in the current month. This error is connected with one in the actual code for highlightTodayIfVisible on page 259.

The text states with reference to Example 12-13 "Finally the method makes the document window key and orders it frontmost." No it
doesn't; no such code is contained in Example 12-13. The last thing it does is initializes the internal data model.

example has the follow however the book does not.
you do not save the notes without this code.
-------
// did not find this in book
- (void)textDidChange:(NSNotification *)notification
{
if ([notification object] == infoNotes) {
[[_inspectingDocument selectedItem] setNotes:
[infoNotes string]];

[_inspectingDocument selectedItemModified];
}
}
// same code as textDidEndEditing maybe a misname.
// rich van deren vanderen@pacbell.net

After reassigning the class of the "itemList" matrix to the newly created
class "SelectionNotifyMatrix" in Interface Builder, the book fails to
mention that you need to also reassign the class of the "statusList" matrix
to "SelectionNotifyMatrix" in order for the application to work. This is
done in the example code available for download from your web site, however
is not mentioned in the book.