I use a UIAlertView to show an alert in iPhone6. where delegate is called nil. When I pressed the ok button of alert then it's automatically crashed and there is no error message. It only shows EXC_BAD_ACCESS(code=EXC_I386_GPFLT).
Given bellow the code:
UIAlertView *alert=[[UIAlertView alloc]initWithTitle:#"" message:#"This First ALert" delegate:nil cancelButtonTitle:#"Ok" otherButtonTitles:nil, nil];
[alert show];
Please check it.
UIAlertView *alert=[[UIAlertView alloc]initWithTitle:#"" message:#"This First ALert" delegate:nil cancelButtonTitle:#"Ok" otherButtonTitles:nil];
[alert show];
Thanks :)
You just added extra nil into otherButtonTitles
UIAlertView *alert=[[UIAlertView alloc]initWithTitle:#"" message:#"This First ALert" delegate:nil cancelButtonTitle:#"Ok" otherButtonTitles:nil];
[alert show];
Hop this helps.
Related
I have a problem about order of executing methods.
if (indexPath.row == 2) {
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:nil
message:#"Data will be downloaded"
delegate:self
cancelButtonTitle:#"OK"
otherButtonTitles:nil];
[alert show];
if([app getData]){
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:nil
message:#"Data is downloaded."
delegate:self
cancelButtonTitle:#"OK"
otherButtonTitles:nil];
[alert show];
}
}
When I run this code snippet, I want to first show an alert view. However, it calls the getData method before showing alert view. Once the getData method is completed, alertView comes to the window.
How can I correct this?
The function is called asynchronously therefore appData gets called before the first alert view is visible. Change your code to this:
if (indexPath.row == 2) {
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:nil
message:#"Data will be downloaded"
delegate:self
cancelButtonTitle:#"OK"
otherButtonTitles:nil];
[alert show];
}
The below method will be called when the user presses OK on your first alert, but it means that while the first alert is visible, your code for appData would not start.
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
if([app getData]){
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:nil
message:#"Data is downloaded."
delegate:nil
cancelButtonTitle:#"OK"
otherButtonTitles:nil];
[alert show];
}
}
Note: Remember to add UIAlertViewDelegate in your view controller
I don't have Xcode with me, but I'll take a stab at it anyway. Your problem is because the alert won't show until the main loop iterates. And it won't iterate until your getData method is executed since you're doing this on the main thread. So you need to fork.
Try wrapping your if() in something like this:
dispatch_async(dispatch_get_main_queue(),
^ {
if([app getData]){
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:nil
message:#"Data is downloaded."
delegate:self
cancelButtonTitle:#"OK"
otherButtonTitles:nil];
[alert show];
}
});
It's because the run loop must continue running so [UIAlertView show] is asynchronous and will not block the current thread. If the main thread was blocked then no user interface events could be delivered.
If you want something to occur after the first alert view is dismissed then do it within the alertView:clickedButtonAtIndex: delegate method.
Fresh and green newbie here. I just started programming and already got stuck with UIAlert. I've searched on this site but there are so many postings and as I said I am kinda new to all this so I don't know what to really look for. This is what I have.
-(void)showError {
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"Error"
message:#"Please try again later. Have a nice day."
delegate:nil
cancelButtonTitle:#"Dismiss"
otherButtonTitles:nil];
}
Need to do
[alert show];
to present
Code should be :
-(void)showError {
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"Error"
message:#"Please try again later. Have a nice day."
delegate:nil
cancelButtonTitle:#"Dismiss"
otherButtonTitles:nil];
[alert show];
[alert release];
}
[alert show];
I always forget this too. Happy Coding.
-(void)showError
{
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"Error"
message:#"Please try again later. Have a nice day."
delegate:nil
cancelButtonTitle:#"Dismiss"
otherButtonTitles:nil];
[alert show];
}
I'm very new to iOS and Objective C. I have the following code to create an alert view in iOS7 for an iPhone application:
if ([tracker exceededGoal]){
[UIAlertView] *alert = [[UIAlertView alloc] initWithTitle:#"Done" message:#"You acheived your goal!" delegate:nil cancelButtonTitle:#"ok" otherButtonTitles:nil];
[alert show];
[alert release];
}
I'm getting the following error:
Use of Undeclared identifier 'alert'
Expected identifier
What did I do wrong?
Remove the brackets here: UIAlertView *alert =
i have create two UIAlertView views in one method. Code like below
-(void) alert{
UIAlertView *alert_1 = [[UIAlertView alloc] initWithTitle:#"Message" message:#“Alert 1” delegate:nil cancelButtonTitle:#"OK" otherButtonTitles:nil];
[alert_1 show];
UIAlertView *alert_2 = [[UIAlertView alloc] initWithTitle:#"Message" message:#“Alert 2” delegate:nil cancelButtonTitle:#"OK" otherButtonTitles:nil];
[alert_2 show];
}
after call this method. iPhone app will appear popup for 2 times.
first appear is alert_1, disappear alert_1 and appear alert_2
after user press ok button in alert_2 thn appear alert_1
should be remove alert_1 when appear alert_2
is possible to remove previous alert view?
Send message - (void)dismissWithClickedButtonIndex:(NSInteger)buttonIndex animated:(BOOL)animated to alert1.
UIAlertView *alert_1 = [[UIAlertView alloc] initWithTitle:#"Message" message:#“Alert 1” delegate:nil cancelButtonTitle:#"OK" otherButtonTitles:nil];
[alert_1 show];
[alert_1 dismissWithClickedButtonIndex:0 animated:YES];
UIAlertView *alert_2 = [[UIAlertView alloc] initWithTitle:#"Message" message:#“Alert 2” delegate:nil cancelButtonTitle:#"OK" otherButtonTitles:nil];
[alert_2 show];
I am not clear about what your requirement is. But from what I understood you want alert_2 to popup first and when clicked on the "OK" button you want to dismiss that alert view and popup alert_1
- (void) alertview
{
alert_1 = [[UIAlertView alloc] initWithTitle:#"Alert 1" message:#"Message" delegate:nil cancelButtonTitle:#"OK" otherButtonTitles:nil, nil];
[alert_1 setTag:1];
alert_1.delegate = self;
alert_2 = [[UIAlertView alloc] initWithTitle:#"Alert 2" message:#"Message" delegate:nil cancelButtonTitle:#"OK" otherButtonTitles:nil];
[alert_2 setTag:2];
alert_2.delegate = self;
[alert_2 show];
}
- (void) alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex
{
if (alertView.tag ==2)
{
[alert_1 show];
}
}
Please note to declare your alert views in your .h file
Get UIAlertView by its tag or #Property and use this [myAlertView dismissWithClickedButtonIndex:-1 animated:YES];
I have this code:
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:title message:msg delegate:nil cancelButtonTitle:#"OK" otherButtonTitles:nil];
[alert show];
[alert release];
The problem is this code crash before it shows the alert, I have tested it on lower iOS and it work but on iOS 6 it crash.
I found the answer. I coded:
[alert performSelectorOnMainThread:#selector(show) withObject:nil waitUntilDone:YES];
instead of
[alert show];
it crash because the process might not be performed in the main thread.
Source from:
https://stackoverflow.com/a/12475858/1179680