Question

I am using a UITableView that points to a UITabBarController to display a series of UIWebViews within these tabs.

I would like define a string to be used to construct a URL for each tab based on the item selected. The issue I am facing is how to pass the URL to the StateTrendViewController controller.

StateTableViewController.h

#import <UIKit/UIKit.h>

@interface StateTableViewController : UITableViewController
{
    NSArray *StateList;
}

@property (nonatomic, retain) NSArray *StateList;

- (void) buildStateList;

@end

StateTableViewController.m

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return [StateList count];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];

    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
    }

    NSInteger rowNumber = indexPath.row;
    NSString *stateName = [StateList objectAtIndex:rowNumber];

    cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
    cell.textLabel.text = stateName.capitalizedString;

    return cell;
}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    [tableView deselectRowAtIndexPath:indexPath animated:YES];

    NSInteger rowNumber = indexPath.row;
    NSString *stateName = [StateList objectAtIndex:rowNumber];

    [[self.navigationController.viewControllers objectAtIndex:2] setTitle:stateName.capitalizedString];
}

StateTrendViewController.h

    #import <UIKit/UIKit.h>

@interface StateTrendViewController : UIViewController
{
    IBOutlet UIWebView *StateTrendView;
    IBOutlet NSString *ViewURL;
}

@property (nonatomic, retain) UIWebView *StateTrendView;
@property (nonatomic, retain) NSString *ViewURL;

@end

StateTrendViewController.m

    #import "StateTrendViewController.h"

@implementation StateTrendViewController

@synthesize StateTrendView;
@synthesize ViewURL;

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void) viewWillAppear:(BOOL)animated 
{
    NSString *baseURL = @"https://www.google.com/search?q=";
    NSString *state = @"test";

    NSString *fullURL = [baseURL stringByAppendingString:state];
    NSURL *url = [NSURL URLWithString:fullURL];

    NSURLRequest *requestObj = [NSURLRequest requestWithURL:url]; [StateTrendView loadRequest:requestObj];
}

I need to replace the static setting with the sting passed to the controller using the ViewURL property I have setup:
NSString *state = @"test";

I am using a Storyboard in my project in Xcode 4.2.1. How should I go about passing that string value to my controller?

Answer 1

If all you are passing is a string, the simplest way might be to define a property on your the view controller you are presenting to hold the string. I notice you already have one, *ViewURL defined, but I’m not sure if that’s what you’ve setup for this specific task or if that is already intended for something else.

Based on the code you’ve shared, I’m assuming that in your didSelectRowAtIndexPath in your table controller, the controller you are setting the title, and presumably later pushing, is an instance of a StateViewController:

[[self.navigationController.viewControllers objectAtIndex:2] setTitle:stateName.capitalizedString];

If this line does indeed reference an instance of StateTrendViewController, you would assign your string in the same way you’re assigning title. This needs to be set before you segue into the new view controller (I don’t see that code):

[[self.navigationController.viewControllers objectAtIndex:2] setViewURL:@"MyPassedString"] //assign custom property

When your view controller appears on screen, it will have it’s property ViewURL already set.

Also note that your naming style for instance variables is not a standard cocoa convention, ivars beginLowerCase. Additionally, it is unusual and may not work to push a TabBar controller inside an existing nav controller, presumably from table view view controller inside an existing nav controller. Typically a TabBar is considered a top-level navigational construct, and you may wish to rethink your architecture accordingly.