I have this code:
//SHOW ALERT
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"Actualizado"
message:#"Se ha actualizado todo" delegate:self
cancelButtonTitle:#"Aceptar" otherButtonTitles:nil, nil];
[alert show];
and this
- (void)alertView:(UIAlertView *)alert
clickedButtonAtIndex:(NSInteger)buttonIndex {
NSLog(#"ALgo"); }
and got the following error:
-[__NSCFType alertView:clickedButtonAtIndex:]:
unrecognized selector sent to instance 0xdc559a0
Help please.
Thanks
Looks like you might be releasing the object or view that handles the alertView:clickedButtonAtIndex: selector (the delegate). Make sure you keep it until your UIAlertView has been dealt with.
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"Actualizado" message:#"Se ha actualizado todo" delegate:self cancelButtonTitle:#"Aceptar" otherButtonTitles:nil, nil];
try this
have you added the UIAlertViewDelegate to your header file?
e.g
#interface yourclass: UIViewController
check if this may be the reason
If your alertView is created inside a object instantiated from a ViewController, you need to keep a pointer to that object in the ViewController.
Related
I have a very simple process running where after each round of a simple game the scores are calculated, labels updated and all the normal, very simple stuff. I have a UIAlertView that informs the player of how s/he performed. I use a UIAlertViewDelegate to postpone all the updates, resetting of controls etc. till after the UIAlertView is dismissed. The methods are [startNewRound],[startOver] and [updateLabels]. It's fairly obvious what they all do. Anyway, when the user hits round ten, I've made another UIAlertView that informs the player that the game has ended and shows the overall score. Again, I hoped to use a delegate to postpone the resets till after the AlertView is dismissed. The only problem is, with the endGame AlertView, it seems to be using the first AlertView's delegate method causing the game to continue with a new round and not start from the beginning. I hope this makes sense. Anyway, here are snippets of my code.
if (round == 10){
UIAlertView *endGame = [[UIAlertView alloc]
initWithTitle: #"End of Game"
message: endMessage
delegate:self
cancelButtonTitle:#"New Game"
otherButtonTitles:nil];
[endGame show];
}
else {
UIAlertView *alertView = [[UIAlertView alloc]
initWithTitle: title
message: message
delegate:self
cancelButtonTitle:#"Next"
otherButtonTitles:nil];
[alertView show];
}
And then the delegate methods:
- (void)alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex
{
[self startNewRound];
[self updateLabels];
}
- (void)endGame:(UIAlertView *)endGame didDismissWithButtonIndex:(NSInteger)buttonIndex
{
[self startOver];
}
So there it is. As I mentioned, the endGame AlertView appears to be using alertView's delegate, thus not activating the [self startOver] method. All the methods are working, it's just the AlertView is using the incorrect delegate method. Regards, Mike
Change your code like this,
if (round == 10){
UIAlertView *endGame = [[UIAlertView alloc]
initWithTitle: #"End of Game"
message: endMessage
delegate:self
cancelButtonTitle:#"New Game"
otherButtonTitles:nil];
endGame.tag = 111;
[endGame show];
}
else {
UIAlertView *alertView = [[UIAlertView alloc]
initWithTitle: title
message: message
delegate:self
cancelButtonTitle:#"Next"
otherButtonTitles:nil];
alertView.tag = 222;
[alertView show];
}
and delegate method as,
- (void)alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex
{
if(alertView.tag == 111)
{
[self startNewRound];
[self updateLabels];
}
else if(alertView.tag == 222)
{
[self startOver];
}
}
You cant have two delegate method for dismisswithbuttonindex, you need to handle this situation with tag.
Give both alert view a different tag and check it on delegate object. Thus you can differentiat the both alert view.
I create a class to call UIAlertview show on my screen. I write the UIAlert function in another class. Both these two classes are not my viewController class.
I use this UIAlert, which is a UITextfield inside, to store texts into a plist file.
here is the class to call UIAlert:
#import "Story.h"
#implementation Story
...
+ (void)stage1
{
AlertClass *pointer = [AlertClass new];
[pointer doAlert];
}
here is the class AlertClass.m file:
- (void)doAlert
{
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"Title" message:#"Message" delegate:self cancelButtonTitle:#"Done" otherButtonTitles:nil];
alert.alertViewStyle = UIAlertViewStylePlainTextInput;
[alert show];
}
//this makes crash!
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex{
self.storyFlow.text = [alertView textFieldAtIndex:0].text;
}
Before I add UIAlertViewDelegate in the .h and override the method "clickedButtonAtIndex", it works great. However, I need to store some data from the UITextfield inside the alert view. I get crash and don't know the message it responds as following.
Please help me to solve this problem. Thanks.
[crash pic] https://dl.dropbox.com/u/47381923/crash.tiff
do an NSLog on the text you get back from the Alert View to see whether that is the crash or the subsequent 'self.storyFlow.text = ' is causing it. Perhaps self.storyFlow has not been created yet (with alloc/init)
I need help on dismissing a UIAlertView programmatically. Currently I have this
UIAlertView *alert1 = [[UIAlertView alloc]initWithTitle:#"title" message:#"message" delegate:nil cancelButtonTitle:nil otherButtonTitles:nil];
then later on I call this
[alert1 dismissWithClickedButtonIndex:0 animated:NO];
but nothing happens.
You need to set two things.
1. include your .h file : <UIAlertViewDelegate>
2. please follow below implementation...
UIAlertView *alert1 = [[UIAlertView alloc]initWithTitle:#"title" message:#"message" delegate:nil cancelButtonTitle:nil otherButtonTitles:nil];
[alert1 show];
[self performSelector:#selector(dismiss:) withObject:alert1 afterDelay:1.0];
the dismiss method will be...
-(void)dismiss:(UIAlertView*)alert
{
[alert dismissWithClickedButtonIndex:0 animated:YES];
}
I hope this will help you.
I encountered this problem too.
In my case, for some reason calling:
[alert dismissWithClickedButtonIndex:0 animated:NO];
didn't work always (yes, even calling it on UI thread and yes, alert != nil), instead simply setting the animated flag to YES it worked:
[alert dismissWithClickedButtonIndex:0 animated:YES];
Maybe it's an Apple bug...
you should display it first:
UIAlertView *alert1 = [[UIAlertView alloc]initWithTitle:#"title" message:#"message" delegate:self cancelButtonTitle:#"Cancel" otherButtonTitles:nil];
[alert1 show];
then in delegate method
- (void)alertView:(UIAlertView *)alertView willDismissWithButtonIndex:(NSInteger)buttonIndex{
if(buttonIndex==0){
// do something
}
}
The methods you called is correct.
I guess the alert1 is nil when your call the method dismissWithClickedButtonIndex:animated:
Try to check your variable alert1.
You can use the delegate method -alertView:didDismissWithButtonIndex: instead—it gets called once the alert view’s been removed from the screen, OR better approach is , use a background thread, e.g. with -performSelectorInBackground:withObject:, to handle whatever processing you need to do.
in my Alert View, there is two button, OK and Cancel. When the user click the OK button, the delegate method dismissWithClickedButtonIndex:animated get called, and if the index is 0, then i get called to a method to execute some code:
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"Alert"
message:#"Are you sure you want to exit"
delegate:self cancelButtonTitle: #"OK"
otherButtonTitles: #"Cancel",nil];
[alert show];
[alert release];//release the reference
Delegate method:
- (void)alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex{
if (buttonIndex==0) {
[self aMethod];
}
}
-(void)aMethod{
//Some useful code
}
Now, what i want to instead of all this, is to execute the code of the aMethod method in the AlertView directly, without referring to A delegate method and a method which get called, something like that:
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"Alert"
message:#"Are you sure you want to exit"
delegate:self cancelButtonTitle: #"OK" //Put here some useful code
otherButtonTitles: #"Cancel",nil];
Is it possible?
Unfortunately this is not possible at this time (iOS 5.1). The AlertView class does not support blocks.
I made a pair of UIAlertView and UIActionSheet subclasses that do exactly that. Grab them here:
https://github.com/rydermackay/RMActionSheet
Use them like this:
RMAlertView *alertView = [RMAlertView alertViewWithTitle:#"Alert!" message:nil];
[alertView addButtonWithTitle:#"OK"
action:^{
NSLog(#"OK");
}];
[alertView addCancelButtonWithTitle:#"Cancel"
action:nil];
[alertView show];
EDIT:
From your comments it sounds like you're not familiar with blocks. Read this now. Seriously.
http://developer.apple.com/library/ios/#documentation/cocoa/Conceptual/Blocks/Articles/00_Introduction.html
This is a good one too:
http://www.mikeash.com/pyblog/friday-qa-2009-08-14-practical-blocks.html
In my iPhone app, I have a NSObjectA class and a UIViewController B class. I want to call a instance method in B class from A. I used the following code.
Bclass *vc = [[Bclass alloc]init];
[vc hideAlert:NSString];
[vc release];
and in B class:
- (void)hideAlert:(NSString*)message{
UIAlertView *shareAlrt = [[UIAlertView alloc] initWithTitle:#""
message:message
delegate:self
cancelButtonTitle:#"Ok"
otherButtonTitles:nil];
[shareAlrt show];
[shareAlrt release];
}
and the method called and show a AlertView. When click on the Ok button, I want to navigate to class Cclass.
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
if (buttonIndex == 0)
{
Cclass *vc = [[Cclass alloc]initWithNibName:#"Cclass" bundle:[NSBundle mainBundle]];
[self presentModalViewController:vc animated:NO];
[vc release];
}
}
But when I click on the Ok button, the app crashes. Whats happening here? I have added <UIAlertViewDelegate> in the B class.h file, but still the same error. Please help
I am getting the error code *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFType alertView:clickedButtonAtIndex:]: unrecognized selector sent to instance 0x81baa80'
Just change the method
- (void)hideAlert:(NSString*)message{
UIAlertView *shareAlrt = [[UIAlertView alloc] initWithTitle:#""
message:message
delegate:self
cancelButtonTitle:nil
otherButtonTitles:#"Ok",nil];
[shareAlrt show];
[shareAlrt release];
}
This has been answered by presuming that u have no other button except cancel button titled as "OK". Assumption is made by seeing your displayed code.
You have used Cancel button on which u cant handle delegate to perform any action.
If you look at the documentation of UIAlertViewDelegate class reference
Optionally, you can implement the alertViewCancel: method to take the
appropriate action when the system cancels your alert view. If the
delegate does not implement this method, the default behavior is to
simulate the user clicking the cancel button and closing the view.