Graphics Programs Reference
In-Depth Information
TimeViewController *tvc = [[TimeViewController alloc] init];
[[self window] setRootViewController:hvc];
[[self window] setRootViewController:tvc];
self.window.backgroundColor = [UIColor whiteColor];
[self.window makeKeyAndVisible];
return YES;
}
Build and run the application. As you might expect, you see the
TimeViewControl-
ler
's
view
that you created in
TimeViewController.xib
. Now we need to con-
nect up the subviews.
Since
TimeViewController
is controlling this view hierarchy, it is responsible for
updating the label when the button is tapped. Thus,
TimeViewController
must be
the target of the
UIButton
and have a pointer to the
UILabel
. In
TimeViewCon-
troller.h
, declare an outlet and a method.
@interface TimeViewController : UIViewController
{
IBOutlet UILabel *timeLabel;
}
- (IBAction)showCurrentTime:(id)sender;
@end
Open
TimeViewController.xib
and connect the
timeLabel
outlet of
File's
Owner
(which we now know is the
TimeViewController
) to the
UILabel
. Then
connect the
UIButton
to the
File's Owner
and select
showCurrentTime:
. These
connections are shown in
Figure 7.11
.
Figure 7.11 TimeViewController XIB connections
