iPhone Sub Tabs - Navigation - iphone

Question

I'm in the process of designing UI for an iPhone app, and we are going to have a standard 4 tab bar across the bottom. We are considering using that same tab bar in a contextual way, so that when you tap a search result the options across the bottom will change to be contextual to the item pressed.
Does this way of doing things represent a huge usability issue, or is it Okay to-do if we are consistent about the execution?
screen1 tab navigation across bottom: A B C D:
-a search result is clicked
-new page is focused with detail view of result
screen2 tab navigation across bottom: E F G H:

Answer 1

It's not possible to do that on the same tabBar, you can hide the tabBar and present another tabBar with the desired items, you can hide/show the tabBar using this methods:
- (void)hideTabBar:(UITabBarController *) tabbarcontroller
{
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.5];
for(UIView *view in tabbarcontroller.view.subviews)
{
if([view isKindOfClass:[UITabBar class]])
{
[view setFrame:CGRectMake(view.frame.origin.x, 480, view.frame.size.width, view.frame.size.height)];
}
else
{
[view setFrame:CGRectMake(view.frame.origin.x, view.frame.origin.y, view.frame.size.width, 480)];
}
}
[UIView commitAnimations];
}
- (void)showTabBar:(UITabBarController *) tabbarcontroller
{
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.5];
for(UIView *view in tabbarcontroller.view.subviews)
{
NSLog(#"%#", view);
if([view isKindOfClass:[UITabBar class]])
{
[view setFrame:CGRectMake(view.frame.origin.x, 431, view.frame.size.width, view.frame.size.height)];
}
else
{
[view setFrame:CGRectMake(view.frame.origin.x, view.frame.origin.y, view.frame.size.width, 431)];
}
}
[UIView commitAnimations];
}
You can use these methods like this:
[self hideTabBar:self.tabBarController];
[self showTabBar:self.tabBarController];
When hiding the tabBar, initiate a new one with and add it to the view.