Database Reference
In-Depth Information
Adding Objects to the xib
The first part of the user interface we will work on is the objects in the xib
file. As with most applications, we need to add the
AppDelegate
to the xib so it
will be both instantiated on start-up and properly linked into the application
itself.
Add the AppDelegate
Depending on the whims of the templates within Xcode, the
AppDelegate
may
already be in the xib file upon opening
MainMenu.xib
. If it is, great! Move on to
the next section. If it's not, we need to add it. In addition, please note that
depending on the version of Xcode that is running, the application delegate
could have the application name prepended to it. If it does, we must substitute
that name for any reference to
AppDelegate
in this context.
To add the
AppDelegate
to the xib file, follow these steps:
1.
Find the
NSObject
in the Library palette, and drag it to the xib's window.
2.
Click the name of the
NSObject
. When it is editable, change it to
AppDelegate
.
3.
Go to the Identity tab on the Inspector palette, and change the class of
the object from
NSObject
to
AppDelegate
.
4.
Right-drag from the application to the
AppDelegate
object, and select
Delegate.
When these steps are complete, the
AppDelegate
class will be instantiated when
our application launches, and the application will send all delegate messages
to it.
Adding the NSArrayController Objects
We want our application to display a list of all the recipes in a single window.
To accomplish this, we need to be able to reference the data so it can be dis-
played. So, let's add three
NSArrayController
objects into our xib that reference
that data. Our window then references those
NSArrayController
objects. Once the
NSArrayController
objects are added and configured, the xib looks like
Figure 20,
The main menu xib
, on page 125
.
To add an
NSArrayController
for the recipe entities, follow these steps:
1.
Find the
NSArrayController
object in the library, and drag it to the xib file.
2.
Click the name of the
NSArrayController
. When it is editable, rename it to
Recipes
. If you have trouble getting the element into edit mode, change the
