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
Related
I am trying to create an AlertView which does not have a cancel button.
This is the code I have tried:
alertView.cancelButtonIndex = -1;
It does not seem to work with iOS 7.
Any ideas?
Thanks,
1) With using this code pressing "Do something button" can do some action but will not lead to alertView hiding
UIAlertView *alert = [[[UIAlertView alloc] initWithTitle:#"Title" message:#"The message." delegate:self cancelButtonTitle:nil otherButtonTitles: #"Do something", nil] show];
#pragma mark - UIAlertViewDelegate
- (BOOL)alertViewShouldEnableFirstOtherButton:(UIAlertView *)alertView {
return NO;
}
2) With using this code there will be no buttons on the alertView(I think this is what you actually need)
UIAlertView *alert = [[[UIAlertView alloc] initWithTitle:#"Title" message:#"The message." delegate:self cancelButtonTitle:nil otherButtonTitles:nil] show];
I've got a crash:
*** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: '-[UIKeyboardTaskQueue performTask:] may only be called from the main thread.'
And I could not find a solution for 2 days.
And here is the code:
[alert dismissWithClickedButtonIndex:0 animated:YES];
UIAlertView *noTicketAlert = [[UIAlertView alloc] initWithTitle:#"Aradığınız kriterlere uygun bilet bulunamadı!" message:nil delegate:self cancelButtonTitle:#"Tamam" otherButtonTitles: nil];
[noTicketAlert show];
I triggered this error by attempting to display an alert from a background thread. Fixed like this:
dispatch_async(dispatch_get_main_queue(), ^{
UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:...
[alertView show];
});
I got this error when presenting a UIAlertView normally (no funny button override stuff). It turned out that I was presenting it twice in quick succession. The fix in my case was to remove the erroneous duplicate call.
If you do need to present two alert views at close to the same time, and you get this error, then a fix that works (and addresses the error message itself) is to run the code on the main thread:
[[NSOperationQueue mainQueue] addOperationWithBlock:^
{
// Your code that presents the alert view(s)
}];
Yes, I've found the solution and I share that with you guys.
I tried to override the dismissWithClickedButtonIndex function, and sent unique buttonIndexes
like 9999 for each of my alerts.
That is,
- (void)alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex {
[self viewWillDisappear:YES];
if(buttonIndex == 9999) {
noTicketAlert = [[UIAlertView alloc] initWithTitle:#"Aradığınız kriterlere uygun bilet bulunamadı!" message:nil delegate:self cancelButtonTitle:#"Tamam" otherButtonTitles: nil];
[noTicketAlert show];
}
}
and if I want to display the noticketAlert, I call this method like :
[alert dismissWithClickedButtonIndex:9999 animated:YES];
If you have a custom button make sure you implement the delegate method:
- (BOOL)alertViewShouldEnableFirstOtherButton:(UIAlertView *)alertView
{
return YES;
}
if this selector is not found then the program with crash..
For those looking for the Swift 2 answer to this issue, I ran into a similar problem and solved it with #Dave Batton's solution
dispatch_async(dispatch_get_main_queue(), {
self.performSegueWithIdentifier("loginSegue", sender: self)
})
I have the code to make it so a notification pops up when I press a button. I want it so it appears when 10 seconds is up.
I know i need to do this:
(NSTimer *)scheduledTimerWithTimeInterval:(NSTimeInterval)seconds invocation:
(NSInvocation *)invocation repeats:(BOOL)repeats
My action is:
{
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"UIAlertView"
message:[NSString stringWithFormat:#"%d", hi]
delegate:hi
cancelButtonTitle:#"Ok"
otherButtonTitles: nil];
[alert show];
}
You can just do:
[self performSelector:#selector(actionMethodName) withObject:nil afterDelay:10];
If you replace actionMethodName with the true method name.
If you want to use the timer route (which is perfectly valid too) it's easier to use scheduledTimerWithTimeInterval:target:selector:userInfo:repeats: than to create an invocation. If you do this, keep a reference to the timer and invalidate it when you're done.
Based on the updated question details, using a timer and invalidating it is becoming a more preferable method, cancelling perform selector is doable but it isn't as clear as the timer route. I'll show the code for the perform selector route anyway:
- (void)startEverything
{
[self performSelector:#selector(showAlert) withObject:nil afterDelay:10];
}
- (void)handleButtonTap:(id)sender
{
[NSObject cancelPreviousPerformRequestsWithTarget:self selector:#selector(showAlert) object:nil];
}
- (void)showAlert
{
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"UIAlertView"
message:[NSString stringWithFormat:#"%d", hi]
delegate:nil
cancelButtonTitle:#"Ok"
otherButtonTitles:nil];
[alert show];
}
Using timers would have the same method structure, but would require a #property to store the timer and instead of cancelPreviousPerformRequestsWithTarget... you would [self.timer invalidate]; self.timer = nil;.
try this:
-(IBAction)btnDoneClick:(id)sender {
[NSTimer scheduledTimerWithTimeInterval:10.0 target:self selector:#selector(buttonactionalert) userInfo:nil repeats:NO];
}
-(void) buttonactionalert {
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"UIAlertView"
message:[NSString stringWithFormat:#"%d", hi]
delegate:hi
cancelButtonTitle:#"Ok"
otherButtonTitles: nil];
[alert show];
}
I would personally just use performSelector:withObject:afterDelay: It would look something like this:
// Action on button press
- (IBAction)myActionButtonPress:(id)sender {
// setup the selector to fire in 10 seconds
[self performSelector:#selector(showAlert) withObject:nil afterDelay:10.0];
}
// the selector to be called
- (void)showAlert {
// display alert
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"UIAlertView"
message:#"This alert displayed 10 seconds after button press"
delegate:self
cancelButtonTitle:#"OK"
otherButtonTitles:nil];
[alert show];
}
this would activate your action method after 10 seconds.
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];
}
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.