UIAlertView delegate methods don't response on iOS 5.1 - objective-c

I created an instance of UIAlertView with two buttons and in the interface file of my class(.h) I set the delegate too but still cant get any response when clicking the buttons. Here is my code:
//myClass.h
#interface MainMenu : UIViewController<UIAlertViewDelegate>
-(IBAction)secondAct:(id)sender;
And the implementation
-(IBAction)secondAct:(id)sender
alert = [[UIAlertView alloc] initWithTitle:#"Dear User"
message:#"Your Request Will be Sent To Security"
delegate:nil
cancelButtonTitle:#"Cancel"
otherButtonTitles:#"OK", nil];
[alert show];
[alert autorelease];
}
and the delegate method:
-(void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex{
NSLog(#"UIAlertView delegate works");//this line too isnt displayed
NSString *title=[ alertView buttonTitleAtIndex:buttonIndex ];
if ([title isEqualToString:#"OK"]) {
NSLog(#"OK Pressed");
}//i want to create something like this
}
I did all of the code above but still can't take any action. Whichever of the buttons i click, it dissmisses the alert. What is wrong with this code can any one help?
ANSWER
Dear PeterG. commented to change delegete:nil with delegate:self and it works now.

Delegate should probably be set to self. If it generates an error post it here.
Also I do not think you should autorelease the alert ivar. Try to skip that line and see what happens?

Just give the delegate "self".
-(IBAction)secondAct:(id)sender
alert = [[UIAlertView alloc] initWithTitle:#"Dear User"
message:#"Your Request Will be Sent To Security"
delegate:self
cancelButtonTitle:#"Cancel"
otherButtonTitles:#"OK", nil];
[alert show];
}

Related

Objective-c action before closing the window

How can i assign an action for close button in my window in objective-c?
For example, user clicks on close button and then program asks: "Do you really want to close the window?"
If you want to add message before closing view in Application you need to implement UIAlertView in it, don't forget to add < UIAlertViewDelegate> in .h file
code in action button pressed;
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"Message"
message:#"Do you really want to close the window?"
delegate:self
cancelButtonTitle:#"OK"
otherButtonTitles:nil];
[alert show];
If you want to do something when the button is clicked, implement this delegate method:
- (void)alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex {
// the user clicked OK
if (buttonIndex == 0) {
// Write Close Code here.....
}
}
Define an uialertview
UIAlertView *message;
message= [[UIAlertView alloc] initWithTitle:#"LOGOUT!" message:#"Are you sure to Logout of This app?" delegate:nil cancelButtonTitle:#"OK" otherButtonTitles:nil];
case :
{
[message show];
vc = [mainStoryboard instantiateViewControllerWithIdentifier:#"loginVC"];
[[SlideNavigationController sharedInstance] popAllAndSwitchToViewController:vc withCompletion:nil];
break;}
}
default:
break;
}

popViewController doesn't work with UIAlertView

I am having problem with AlertView. I am trying to use the UIAlertView and after click ok it will return back to the previous screen but it do not seems to work any advice ?
if (xGPSCoordinate==0 && yGPSCoordinate == 0) {
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"Title"
message:#"Failed to load the to get your current location"
delegate:self
cancelButtonTitle:#"Ok"
otherButtonTitles:nil, nil];
[alert show];
[alert release];
return;
[self.navigationController popViewControllerAnimated:YES];
}
or
if (xGPSCoordinate==0 && yGPSCoordinate == 0) {
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"iPoly"
message:#"Failed to load the to get your current location"
delegate:self
cancelButtonTitle:#"Ok"
otherButtonTitles:nil, nil];
[alert show];
[alert release];
[self.navigationController popViewControllerAnimated:YES];
return;
}
both doesn't work
For this purpose you've to use UIAlertView's delegate method.
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex;
First use this in your #interface <UIAlertViewDelegate>
Then set the delegate, self.yourAlertView.delegate=self;
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
if(buttonIndex==0)//first button which should be the OK button
{
[self.navigationController popViewControllerAnimated:YES];
}
}
use the delegate method of UIAlertView, see the answer given by iNoob. It does not make a sense if you write anything after the "return;" statement as the code below "return;" statement will never get executed.
refer apple developer link for more details on UIAlertView delegate http://developer.apple.com/library/ios/#DOCUMENTATION/UIKit/Reference/UIAlertViewDelegate_Protocol/UIAlertViewDelegate/UIAlertViewDelegate.html
or a simple tutorial on alert view
http://mobile.tutsplus.com/tutorials/iphone/uialertview/
You just need to implement UIAlerView Delegate Methods.
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex{}
write your code for Pop to previous Controller here.You can the clicked button index and on the basis of that you can use.Don't for Conform UIAlertViewDelegate to Interface.

How do I send the iOS user an instant local notification?

I simply want a notification to pop up when the user presses a button. No servers or timers needed. All the tutorials I can find seem to involve one of these two.
Maybe something like this:
-(IBAction) buttonPressed: (UIButton *)sender{
UIAlertView *alert = [[UIAlertView alloc] initWithTitle: [NSString stringWithFormat:#"You pressed button %#", sender.tag]
message: #"message"
delegate: self
cancelButtonTitle: #"Ok"
otherButtonTitles: nil]];
[alert show];
}
It would look something like this:
You can also customize the alert view a bit, so it could potentially have a textfield for text entry:
With UIAlertViews, you can also implement protocol methods like – alertView:clickedButtonAtIndex: and – alertView:willDismissWithButtonIndex:to perform different actions depending on which alert button they pressed.
Here's a good tutorial on UIAlertViews and implementing their protocol methods: http://mobile.tutsplus.com/tutorials/iphone/uialertview/.
If you don't want to use UIAlertViews and instead want a more customizable modal view, check out these two great libraries called UAModalPanel and MJPopupViewController. You can check out the links for images, demos, and more info on the two libraries, including links to their github pages where you can download them.
Hope this helps!
UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:title message:message delegate:delegate cancelButtonTitle:cancelMessage];
[alertView show];
It is important to make sure the alert is shown on the main thread, where all the UI is handled. Otherwise you may get some weird errors and/or crashes. You can use GCD to dispatch to the main thread:
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"Alert Test"
message:#"This is an alert test."
delegate:self
cancelButtonTitle:#"Cancel"
otherButtonTitles:#"OK",
nil];
dispatch_async(dispatch_get_main_queue(), ^{
[alert show];
});

Alert View in the Beginning and the End of a void

I have a Void. This void do something really slow, so at the beginning of Void I put an alert, and in the end I put another warning. Like here:
-(void)action {
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"Start" message:#"Start." delegate:self cancelButtonTitle:#"Ok." otherButtonTitles:nil];
[alerta show];
[alert release];
//Something really slow
UIAlertView *alertEnd = [[UIAlertView alloc] initWithTitle:#"End" message:#"End." delegate:self cancelButtonTitle:#"Ok." otherButtonTitles:nil];
[alertEnd show];
[alertEnd release];
}
But when I run this code, the alerts are only shown at the end of the Void, after all the slow action.
How can I fix this?
First of all: try to avoid using many alerts since it's not humane to you users. Show UIActivityIndicator instead.
If you must, then try this code for showing the first alert:
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"Start" message:#"Start." delegate:self cancelButtonTitle:#"Ok." otherButtonTitles:nil];
[alert performSelector: #selector(show)
onThread: [NSThread mainThread]
withObject: nil
waitUntilDone: NO];
you will have to separate the two in two methods and then call one using
[self performSelector: afterDelay:]
method

UIAlertView without any buttons

I wanted to know whether the following code is okay or not. I am trying to dismiss the alertView automatically after 2 seconds (and without any buttons in the alertView) from the "timedAlert" method.
//this is in another method
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:nil message:#"Login successful." delegate:self cancelButtonTitle:nil otherButtonTitles:nil];
[alert show];
[alert release];
[self timedAlert];
}
-(void)timedAlert
{
[self performSelector:#selector(dismissAlert:) withObject:alert afterDelay:2];
}
-(void)dismissAlert:(UIAlertView *) alertView
{
[alertView dismissWithClickedButtonIndex:nil animated:YES];
}
If the cancelButton of the alertView is set to "nil", how will the "[alertView dismissWithClickedButtonIndex:0 animated:YES];" thing work??? I tried making the cancelButton "nil" and it worked, but cant figure out how....
P.S: I call the timedAlert method from another
Any help is appreciated! Thank you!
First let me say it would be better if you handle this with a custom view, but with that said the problem looks to be with
[alert release];
You are releasing the object before you are done with it (I am surprise it does not crash).
Do something like this
// other code
alert = [[UIAlertView alloc] initWithTitle:nil message:#"Login successful." delegate:self cancelButtonTitle:nil otherButtonTitles:nil];
[alert show];
[self performSelector:#selector(dismissAlert:) withObject:alert afterDelay:3.0f];
}
-(void)dismissAlert:(UIAlertView *) alertView
{
[alertView dismissWithClickedButtonIndex:nil animated:YES];
[alertView release];
}
Your code should work, and you should have no problems. I have done this in one of my previous apps. The button is not displayed because the title is nil but I think the instance of the button still exists. Put a breakpoint before closing your alert and take a look at the alert variable, and check to see if there is a buttons array or something, that should tell you how that works.