问题
I'm having a problem getting a UISearchDisplay's text value to be set programatically on load of the view by another view and my question is have I overcomplicated my problem and missed something or am I on the right track of thinking.
Here's the situation: I have a UITabBarController as my root view, there are 2 tabs, both have a UINavigationController setup so I can push views as needed.
Tab 1 has a UITableViewController which is populated with a list of categories.
Tab 2 has a MapView in it's main view but I have done a custom UINavigationItem view to put various buttons and a UISearchDisplay on the rightBarButtonitem area.
The mapview layout and custom navigation item are stored in the same nib as two separate view objects. In Tab 2's viewDidLoad(), I initialise the rightBarButtonItem programatically with:
UIBarButtonItem *btnItem = [[UIBarButtonItem alloc] initWithCustomView:buttonBar];
self.navigationItem.rightBarButtonItem = btnItem;
[btnItem release];
Everything fires up, buttonBar is wired up to an IBOutlet as searchWhat and I can talk to this object from within the mapview's controller class.
If the user is in Tab 1 and taps a cell, I want it to switch to Tab 2 and populate the searchWhat.text and then execute the search code as if someone had typed in the search themselves.
What i'm having trouble with is the order of load and populate on a view.
I can access the 2nd tab from the 1st without any problem and get it to appear with something like:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
NSLog(@"Quick Category cell tapped at row %d", indexPath.row);
self.tabBarController.selectedIndex = 1; // change to the search view controller
//[self.tabBarController.selectedViewController viewDidAppear:YES];
UINavigationController *nav = (UINavigationController *)self.tabBarController.selectedViewController;
SearchViewController *srch = [nav.viewControllers objectAtIndex:0];
//NSLog(@"%@", [srch description]);
[srch queueSearchByType:kSearchTypeQuickCategories withData:[catList objectAtIndex:indexPath.row]];
[srch viewDidAppear:YES];
}
Don't worry about catList and SearchViewController, they exist and this bit works to switch tabs.
Here's the problem though, if the user starts the application and selects an item in tab 1, tab 2 appears but the values of the search display text don't get set - because viewDidLoad and viewDidAppear are called in another thread so the execution of queueSearchByType:withData: gets called while the view is still loading and setting up.
If the user selects tab 2 (therefore initialising the subview) and then selects tab 1 and an item, it can populate the search display text.
I can't just change the order of the tabs so that tab2 is first and therefore loads it's subviews to the navigation bar as the project specification is category search first.
Have I missed something very simple? What I need to do is wait for the second tab to fully appear before calling queueSearchByType:withData: - is there a way to do this?
At the moment, i've implemented a queue the search, check for a queue search approach, this seems to be a bit long winded.
回答1:
Ok, I don't like answering my own question but it appears my fears were right, basically if you want a UINavigationItem that is a custom view (ie, to put a search bar and various other buttons up on the nav controller) and be able to switch to and populate them from another tab on a tab bar controller, then you need to put the subview in it's own class which is a subclass of UIViewController and then make delegation your friend (which it already is), i've provided an example in case anybody needs to repeat it which i've put on my blog HERE.
http://www.jamesrbrindle.com/developer/ios-developer/howto-add-a-custom-uinavigationitem-to-a-uinavigationcontroller-with-delegation.htm
If anyone disagrees and thinks this can be simpler, please let me know or rate this post
来源：https://stackoverflow.com/questions/6020222/ios-setting-text-in-nib-subview-from-view-in-uitabbar-uinavigationcontroller-ap