Question

I am trying to detect whether the user pressed the cancelButton or destructive button on the actionSheet. Depending on his/her input, I would like to modify the alert message shown on the screen.

So I tried using if to check the buttonIndex, but it turns out that the buttonIndex value does not change with the input from the user.

UIActionSheet *informUser = [[UIActionSheet alloc] initWithTitle:@"Missing data" delegate:self cancelButtonTitle:@"Thanks for telling me!" destructiveButtonTitle:@"I have ignored it!" otherButtonTitles:nil];

    [informUser showInView:self.view];

//        NSLog(@"Cancel button = %d", informUser.cancelButtonIndex);
//        NSLog(@"Destructive button = %d", informUser.destructiveButtonIndex);

    if(informUser.cancelButtonIndex == 1)
    {
        NSString *msg = [[NSString alloc] initWithFormat:@"Pls enter the number."];

        UIAlertView *alertUser = [[UIAlertView alloc] initWithTitle:@"Missing data" message:msg delegate:self cancelButtonTitle:@"Thanks!" otherButtonTitles:nil];

        [alertUser show];
    }

I also tried using a separate method:

-(void)actionSheet:(UIActionSheet *)actionSheet didDismissWithButtonIndex:(NSInteger)buttonIndex;

but, I get wrong results when I have multiple UIAlert at different points on the same screen.

In short, I would like to use a different UIAlert for different actions/inputs from user. Therefore, how do I detect which button on the actioSheet has been pressed by the user?

Thank you.

Answer 1

Implement the UIActionSheetDelegate and use the method:

– actionSheet:clickedButtonAtIndex: 

The index defines which button you tapped.

If you don’t want to use the button index you can get the button title of the tapped button with

– buttonTitleAtIndex:

Then you can compare the result to your button title string.

Read more in the Apple docs

---

Edit:
If you want to use more actionsheets you can set the tag-value for each of them. E.g. ActionSheet1 has actionsheet.tag = 1 and so on.

Then you can switch in – actionSheet:clickedButtonAtIndex: by the tag of the given actionsheet. E.g.:

switch (actionsheet.tag) {
    case 1: 
        // do stuff
    break;
    case 2: 
        // do stuff
    break;
    default: break;
}

---

Edit 2:
This is a sample class that should show you the logic:

Header file:

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController <UIActionSheetDelegate>

@end

Implementation file:

#import "ViewController.h"

@implementation ViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.

    UIActionSheet *as1 = [[UIActionSheet alloc] initWithTitle:@"Title" delegate:self cancelButtonTitle:@"Cancel" destructiveButtonTitle:@"Delete" otherButtonTitles:@"Ok", nil];
    as1.tag = 0;
    as1.delegate = self;

    UIActionSheet *as2 = [[UIActionSheet alloc] initWithTitle:@"Title2" delegate:self cancelButtonTitle:@"Cancel2" destructiveButtonTitle:@"Delete2" otherButtonTitles:@"Ok2", nil];
    as2.tag = 1;
    as2.delegate = self;
}


- (void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex {
    switch (actionSheet.tag) {
        case 0: // as1
            switch (buttonIndex) {
                case 0:
                    // button index 0
                    break;

                case 1:
                    // button index 1
                    break;

                //....

                default:
                    break;
            }
            break;

        case 1: // as2
            switch (buttonIndex) {
                case 0:
                    // button index 0
                    break;

                case 1:
                    // button index 1
                    break;

                    //....

                default:
                    break;
            }
            break;

        default:
            break;
    }
}

@end