UIAlertView not showing

Question

I have a small problem with one of my UIAlertViews. I'm trying to show it, do some tasks, and then dismiss automatically. This is the code I'm using currently:

callingTaxi = [[UIAlertView alloc] initWithTitle:@"" message:@"検索中" delegate:nil cancelButtonTitle:nil otherButtonTitles:nil, nil];
[callingTaxi show];
/* Do some tasks */
[callingTaxi dismissWithClickedButtonIndex:0 animated:YES];
[callingTaxi release];

However, the UIAlertView only shows half-way. I can see the background darken, but then after the tasks have completed, the alert view quickly appears and then disappears, again.

Any ideas how to solve this issue?

Ben

can you elaborate on your solution as I have the same problem, thanks! — Rasman, May 29 '11 at 20:03

fresskoma · Accepted Answer · 2011-01-10T13:28:40.960

3

It does show, but you dismiss it right away, instead of waiting for the user to do something, with

[callingTaxi dismissWithClickedButtonIndex:0 animated:YES];

There is no time for iOS to render it completely. Anyway, this is not how dismissWithClickedButtonIndex is supposed to be used. What are you trying to achieve here?

Edit: I guess you need to assign a delegate to the UIAlertView, and let the delegate handle what happens inside the AlertView.

edited Jan 10 '11 at 13:28

answered Jan 10 '11 at 13:15

fresskoma

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can you explain more what you mean by "the delegate handle what happens inside the AlertView" – Rasman May 29 '11 at 20:06
@Rasman: Take a look at http://mobile.tutsplus.com/tutorials/iphone/uialertview/ which explains how you can create a UIAlertViewDelegate in order to handle button clicks from a UIAlertView – fresskoma May 29 '11 at 20:10

score 1 · Answer 2 · answered Jan 10 '11 at 13:14

1

You should not close it inside the same function which shows it, close it by timer, or as reaction to another event.

answered Jan 10 '11 at 13:14

Nickolay Olshevsky

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score 1 · Answer 3 · answered May 29 '11 at 21:34

You don't need a delegate. The problem is that the tasks you do must happen on a background thread, so the main thread is left alone to update the screen.

If you update your code to use blocks and dispatch queues, everything will work:

callingTaxi = [[UIAlertView alloc] initWithTitle:@"" message:@"検索中" delegate:nil cancelButtonTitle:nil otherButtonTitles:nil, nil];
[callingTaxi show];
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, NULL), ^{
    /* Do some tasks */
    dispatch_async(dispatch_get_main_queue(), ^{
        // this code is back on the main thread, where it's safe to mess with the GUI
        [callingTaxi dismissWithClickedButtonIndex:0 animated:YES];
        [callingTaxi release];
    });
});

score 0 · Answer 4 · answered Jan 10 '11 at 13:21

you should create a method for the alertview

- (void) alertView: (UIAlertView *) alertView didDismissWithButtonIndex:(NSInteger)buttonIndex{
// Do stuff
// Or if you have multiple buttons, you could use a switch

[callingTaxi release];

Or you could Autorelease..

But x3ro has given the correct answer, you call the method yourself instead of waiting for the user to press the button..

score 0 · Answer 5 · answered Aug 15 '11 at 00:00

0

the uialertview is dismissed by: [callingTaxi dismissWithClickedButtonIndex:0 animated:YES]; before the user can read it.

How long do you intend to have the end user read it???

answered Aug 15 '11 at 00:00

Eman yalpsid

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UIAlertView not showing

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