I am new on IOS. I have a sample project and trying to learn Obj-C on that.
Now I am on the stage that is about learning how to use UIAlertController.
And I have a code like that:
if (loanAmount == 0) {
UIAlertController *ErrorMessage =[UIAlertController alertControllerWithTitle:#"Invalid amount" message:#"Enter a valid number" preferredStyle:UIAlertControllerStyleAlert];
} else
{ // sets labels
self.interestLabel.text = [NSString stringWithFormat:#"%i%c",interestRate,percentage];
self.periodLabel.text = [NSString stringWithFormat:#"%i months",months];
self.totalLabel.text = [NSString stringWithFormat:#"$%i",(loanAmount + tinterest)];
========================================================================
But When I run the simulator. There should be pop up message on Simulator. Instead of that, there is an error that says:
015-10-11 13:56:39.985 iBank[8055:1231178] Attempting to load the view of a view controller while it is deallocating is not allowed and may result in undefined behavior (<UIAlertController: 0x7ca82400>)
Any help would be greatly appreciated
try this
if (loanAmount == 0) {
UIAlertController * ErrorMessage = [UIAlertController
alertControllerWithTitle:#"Invalid amount"
message:#"Enter a valid number"
preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *cancelAction = [UIAlertAction
actionWithTitle:NSLocalizedString(#"Cancel", #"Cancel action")
style:UIAlertActionStyleCancel
handler:^(UIAlertAction *action)
{
NSLog(#"Cancel action");
}];
UIAlertAction *okAction = [UIAlertAction
actionWithTitle:NSLocalizedString(#"OK", #"OK action")
style:UIAlertActionStyleDefault
handler:^(UIAlertAction *action)
{
NSLog(#"OK action");
}];
[ErrorMessage addAction:cancelAction];
[ErrorMessage addAction:okAction];
[self presentViewController: ErrorMessage animated:YES completion:nil];
}
else
{
self.interestLabel.text = [NSString stringWithFormat:#"%i%c",interestRate,percentage];
self.periodLabel.text = [NSString stringWithFormat:#"%i months",months];
self.totalLabel.text = [NSString stringWithFormat:#"$%i",(loanAmount + tinterest)];
}
Related
I have added a UIAlterController to my view. IT triggers fine, looks fine, and has its action, however tapping the Cancel action does nothing, it doesnt run any code, even if i add a block it wont execute it, it just doesnt seem to recognise the tap at all.
The code looks fine to me, so is there some other cause?
- (void)connectionFailed:(NSString *)title {
NSString *message = nil;
if ([title isEqualToString:NSLocalizedString(#"Connection Refused", #"connection Refused")]) {
message = NSLocalizedString(#"You do not have permission to use this console", #"incorrect permissions message");
}
else {
message = NSLocalizedString(#"Connection Failed", #"connection failed error message");
}
dispatch_async(dispatch_get_main_queue(), ^{
UIAlertController *alertController = [UIAlertController
alertControllerWithTitle:title
message:message
preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:#"Cancel"
style:UIAlertActionStyleDefault
handler:nil];
[alertController addAction:cancelAction];
[self presentViewController:alertController animated:YES completion:nil];
});
Edit: it appears the issue is down to view leaks causing problems, not sure of the fix but here is the breakdown in debugging:
debugging image of view stack
Use this:
UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:#"Cancel"
style:UIAlertActionStyleCancel
handler:nil];
Change UIAlertActionStyleDefault to UIAlertActionStyleCancel
Try this:
UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:#"Cancel"
style:UIAlertActionStyleCancel
handler:^(UIAlertAction * _Nonnull action) {
//your code here ...
}];
- (void)connectionFailed:(NSString *)title {
NSString *message = nil;
if ([title isEqualToString:NSLocalizedString(#"Connection Refused", #"connection Refused")]) {
message = NSLocalizedString(#"You do not have permission to use this console", #"incorrect permissions message");
}
else {
message = NSLocalizedString(#"Connection Failed", #"connection failed error message");
}
dispatch_async(dispatch_get_main_queue(), ^{
UIAlertController *alertController = [UIAlertController
alertControllerWithTitle:title
message:message
preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:#"Cancel"
style: UIAlertActionStyleCancel
handler:nil];
[alertController addAction:cancelAction];
[self presentViewController:alertController animated:YES completion:nil];
});
just edited your cancel button alert style....
Try this :
UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:#"Cancel"
UIAlertActionStyleDefault
handler:nil];
I am new to Objective C but have been working on Swift for a while now. I assumed Objective c to be logically similar to swift. I have to present an alert controller while I am processing a json data request; so I had to use dispatch async to get it to work in swift. Here's the code I used in Swift:
func alertMessage(message : String) -> Void {
let alert = UIAlertController(title: "Alert", message: message, preferredStyle: .Alert)
let okAction = UIAlertAction(title: "OK", style: .Default, handler: nil)
alert.addAction(okAction)
dispatch_async(dispatch_get_main_queue(),{
self.presentViewController(alert, animated: true, completion: nil)
})
}
But I tried to do the same thing in objective C like so
- (void)alertMessage : (NSString*) message {
UIAlertController *alert = [UIAlertController alertControllerWithTitle:#"Alert" message:message preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *okAction = [UIAlertAction actionWithTitle:#"OK" style:UIAlertActionStyleDefault handler:NULL];
[alert addAction:okAction];
[dispatch_async(dispatch_get_main_queue(), ^(void){
[self presentViewController:alert animated:true completion:NULL];
})];
}
I'm getting an error "expected identifier". What am I doing wrong?
Its just syntax error. Try following
- (void)alertMessage : (NSString*) message {
UIAlertController *alert = [UIAlertController alertControllerWithTitle:#"Alert" message:message preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *okAction = [UIAlertAction actionWithTitle:#"OK" style:UIAlertActionStyleDefault handler:NULL];
[alert addAction:okAction];
dispatch_async(dispatch_get_main_queue(), ^(void){
[self presentViewController:alert animated:true completion:NULL];
});
}
Because “dispatch_async” is a C function, you should call it like this.
- (void)alertMessage : (NSString*) message {
UIAlertController *alert = [UIAlertController alertControllerWithTitle:#"Alert" message:message preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *okAction = [UIAlertAction actionWithTitle:#"OK" style:UIAlertActionStyleDefault handler:NULL];
[alert addAction:okAction];
dispatch_async(dispatch_get_main_queue(), ^{
[self presentViewController:alert animated:true completion:nil];
});
}
Can try now
- (void)alertMessage : (NSString*) message {
UIAlertController *alert = [UIAlertController alertControllerWithTitle:#"Alert" message:message preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *okAction = [UIAlertAction actionWithTitle:#"OK" style:UIAlertActionStyleDefault handler:NULL];
[alert addAction:okAction];
dispatch_async(dispatch_get_main_queue(), ^(void){
[self presentViewController:alert animated:true completion:nil];
});
}
Output:
Happy coding..
I have this UIAlertController as a utility that accepts two paremeters, the title and the content. I want to modify the "confirm" button. I want to duplicate this utility and add another parameter the will execute a specific function.
-(UIAlertController *) modalWithTitle : (NSString *) title andContent: (NSString *) content{
UIAlertController *alert = [UIAlertController alertControllerWithTitle: title message:content preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *defaultAction = [UIAlertAction actionWithTitle:#"OK" style:UIAlertActionStyleDefault handler:^(UIAlertAction * action){}];
[alert addAction:defaultAction];
return alert;
}
Example code :
UIAlertController *alert =[[ModalController alloc] modalWithTitle:#"Error" andContent:#"Network unavailable."
andAction:<ENTER FUNCTION TO EXECUTE HERE>];
[self presentViewController:alert animated:YES completion:nil];
You can write it like this:
+ (UIAlertController *)modalWithTitle:(NSString *)title andContent:(NSString *)content andHandler:(void (^)(UIAlertAction *))handler {
UIAlertController *alert = [UIAlertController alertControllerWithTitle: title message:content preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *defaultAction = [UIAlertAction actionWithTitle:#"OK" style:UIAlertActionStyleDefault handler:handler];
[alert addAction:defaultAction];
return alert;
}
Usage:
void (^handler)(UIAlertAction *) = ^(UIAlertAction *action) {
// code to execute
};
[[ModalController alloc] modalWithTitle:#"title" andContent:#"content" andHandler:handler];
Another approach:
+ (UIAlertController *)modalWithTitle:(NSString *)title andContent:(NSString *)content andHandler:(void (^)(void))handler {
UIAlertController *alert = [UIAlertController alertControllerWithTitle:title message:content preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *defaultAction = [UIAlertAction actionWithTitle:#"OK" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action) {
handler();
}];
[alert addAction:defaultAction];
return alert;
}
Usage:
void (^block)(void) = ^{
// code to execute
};
[[ModalController alloc] modalWithTitle:#"title" andContent:#"content" andHandler:block];
I'm trying to get a textField value from UIAlertController, but whenever I try to enter the value (Name) and display it on label, the output doesn't show anything.
- (IBAction)button:(id)sender {
UIAlertController * alert = [UIAlertController alertControllerWithTitle:#"Test" message:#"Please Enter your name " preferredStyle:UIAlertControllerStyleAlert];
[alert addTextFieldWithConfigurationHandler:^(UITextField *textField) {
textField.placeholder = #"Person Name ";
textField.textColor = [UIColor blueColor];
textField.clearButtonMode = UITextFieldViewModeWhileEditing;
textField.borderStyle = UITextBorderStyleRoundedRect;
textField.secureTextEntry = NO;
}];
UIAlertAction* yesButton = [UIAlertAction
actionWithTitle:#"ENTER, please"
style:UIAlertActionStyleDefault
handler:^(UIAlertAction * action)
{
//Handle the ENTER button
// how to Display the name in the label
}];
UIAlertAction* noButton = [UIAlertAction
actionWithTitle:#"No, thanks"
style:UIAlertActionStyleDefault
handler:^(UIAlertAction * action)
{
//Handle no button.
}];
[alert addAction:yesButton];
[alert addAction:noButton];
[self presentViewController:alert animated:YES completion:nil];
}
Quick swift example I pulled from an old project
alert.addAction(UIAlertAction(title: "Send", style: UIAlertActionStyle.Default, handler:{ (UIAlertAction)in
if let textFields = alert.textFields {
if let textField = textFields.first {
}
}
}))
In your application it would like something like this:
UIAlertAction* yesButton = [UIAlertAction actionWithTitle:#"ENTER, please" style:UIAlertActionStyleDefault handler:^(UIAlertAction * action)
{
NSArray *textFields = alert.textFields;
// Probably smart to do some nil checking here
NSLogv(#"%#", textFields.first.text);
// add to label like so
label.text = textFields.first.text;
}];
I have tried several ways to use UIAlertController,instead of UIAlertView. I tried several ways but I cannot make the alert action work.
Here is my code that works fine in IOS 8 and IOS 9 but is showing up with deprecated flags. I tried the elegant suggestion below but I can't make it function in this context. I need to submit my app and this is the last thing to address. Thank You for any further suggestions. I am a newbie.
#pragma mark - BUTTONS ================================
- (IBAction)showModesAction:(id)sender {
NSLog(#"iapMade: %d", iapMade3);
// IAP MADE ! ===========================================
if (!iapMade3) {
//start game here
gamePlaysCount++;
[[NSUserDefaults standardUserDefaults]setInteger:gamePlaysCount forKey:#"gamePlaysCount"];
NSLog(#"playsCount: %ld", (long)gamePlaysCount);
if (gamePlaysCount >= 4) {
UIAlertView *alert = [[UIAlertView alloc]initWithTitle:#"Basic"
message: THREE_PLAYS_LIMIT_MESSAGE
delegate:self
cancelButtonTitle:#"Yes, please"
otherButtonTitles:#"No, thanks", nil];
[alert show];
NSString *path = [[NSBundle mainBundle] pathForResource:#"cow" ofType:#"wav"];
_pop =[[AVAudioPlayer alloc] initWithContentsOfURL:[NSURL fileURLWithPath:path] error:NULL];
[_pop play];
[self dismissViewControllerAnimated:true completion:nil];
} else {
if (gamePlaysCount == 1) {
// Create & store the next 5 mins when player gets 3 more lives
nextDateToPlay = [[NSDate date] dateByAddingTimeInterval:60*60*0.1];
NSLog(#"CURRENT DATE: %#", [NSDate date]);
NSLog(#"NEXT DAY: %#", nextDateToPlay);
[[NSUserDefaults standardUserDefaults]setObject: nextDateToPlay forKey:#"nextDateToPlay"];
NSLog(#"nextDateToPlay: %#", nextDateToPlay);
UIAlertView *alert = [[UIAlertView alloc]initWithTitle:#"Basic"
message: THREE_PLAYS_LIMIT_MESSAGE2
delegate:self
cancelButtonTitle:#"Got it!"
otherButtonTitles:#"Start", nil];
[alert show];
} else {
if (gamePlaysCount == 3) {
UIAlertView *alert = [[UIAlertView alloc]initWithTitle:#"Basic"
message: THREE_PLAYS_LIMIT_MESSAGE3
delegate:self
cancelButtonTitle:#"Yep, I Know!"
otherButtonTitles:#"Start", nil];
[alert show];
}
}
}
}
}
// IAP NOT MADE =============================
#pragma mark - ALERTVIEW DELEGATE ============================
-(void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex {
if ([[alertView buttonTitleAtIndex:buttonIndex] isEqualToString:#"Yes, please"]) {
UIStoryboard *storyboard = self.storyboard;
MenuViewController *svc = [storyboard instantiateViewControllerWithIdentifier:#"Store"];
svc.modalTransitionStyle = UIModalTransitionStyleCrossDissolve;
[self presentViewController:svc animated:YES completion:nil];
}
}
From iOS8 Apple provide new UIAlertController class which you can use instead of UIAlertView which is now deprecated, it is also stated in deprecation message:
UIAlertView is deprecated. Use UIAlertController with a preferredStyle
of UIAlertControllerStyleAlert instead
So you should use something like this
UIAlertController * alert = [UIAlertController
alertControllerWithTitle:#"Title"
message:#"Message"
preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction* yesButton = [UIAlertAction
actionWithTitle:#"Yes, please"
style:UIAlertActionStyleDefault
handler:^(UIAlertAction * action) {
//Handle your yes please button action here
}];
UIAlertAction* noButton = [UIAlertAction
actionWithTitle:#"No, thanks"
style:UIAlertActionStyleDefault
handler:^(UIAlertAction * action) {
//Handle no, thanks button
}];
[alert addAction:yesButton];
[alert addAction:noButton];
[self presentViewController:alert animated:YES completion:nil];
//Calling
[self showMessage:#"There is no internet connection for this device"
withTitle:#"Error"];
//Method
-(void)showMessage:(NSString*)message withTitle:(NSString *)title
{
UIAlertController * alert= [UIAlertController
alertControllerWithTitle:title
message:message
preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *okAction = [UIAlertAction actionWithTitle:#"OK" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action){
//do something when click button
}];
[alert addAction:okAction];
UIViewController *vc = [[[[UIApplication sharedApplication] delegate] window] rootViewController];
[vc presentViewController:alert animated:YES completion:nil];
}
If you want to use this alert in NSObject class you should use like:
-(void)showMessage:(NSString*)message withTitle:(NSString *)title{
dispatch_async(dispatch_get_main_queue(), ^{
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:title message:message preferredStyle:UIAlertControllerStyleAlert];
[alertController addAction:[UIAlertAction actionWithTitle:#"OK" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
}]];
[[[[UIApplication sharedApplication] keyWindow] rootViewController] presentViewController:alertController animated:YES completion:^{
}];
});
}
Swift version of new implementation is :
let alert = UIAlertController(title: "Oops!", message:"your message", preferredStyle: .Alert)
alert.addAction(UIAlertAction(title: "Okay.", style: .Default) { _ in })
self.presentViewController(alert, animated: true){}
Xcode 8 + Swift
Assuming self is a UIViewController:
func displayAlert() {
let alert = UIAlertController(title: "Test",
message: "I am a modal alert",
preferredStyle: .alert)
let defaultButton = UIAlertAction(title: "OK",
style: .default) {(_) in
// your defaultButton action goes here
}
alert.addAction(defaultButton)
present(alert, animated: true) {
// completion goes here
}
}
Make UIAlertController+AlertController Category as:
UIAlertController+AlertController.h
typedef void (^UIAlertCompletionBlock) (UIAlertController *alertViewController, NSInteger buttonIndex);
#interface UIAlertController (AlertController)
+ (instancetype)showAlertIn:(UIViewController *)controller
WithTitle:(NSString *)title
message:(NSString *)message
cancelButtonTitle:(NSString *)cancelButtonTitle
otherButtonTitles:(NSString *)otherButtonTitle
tapBlock:(UIAlertCompletionBlock)tapBlock;
#end
UIAlertController+AlertController.m
#implementation UIAlertController (NTAlertController)
+ (instancetype)showAlertIn:(UIViewController *)controller
WithTitle:(NSString *)title
message:(NSString *)message
cancelButtonTitle:(NSString *)cancelButtonTitle
otherButtonTitles:(NSString *)otherButtonTitle
tapBlock:(UIAlertCompletionBlock)tapBlock {
UIAlertController *alertController = [self alertControllerWithTitle:title message:message preferredStyle:UIAlertControllerStyleAlert];
if(cancelButtonTitle != nil) {
UIAlertAction *cancelButton = [UIAlertAction
actionWithTitle:cancelButtonTitle
style:UIAlertActionStyleCancel
handler:^(UIAlertAction *action)
{
tapBlock(alertController, ALERTACTION_CANCEL); // CANCEL BUTTON CALL BACK ACTION
}];
[alertController addAction:cancelButton];
}
if(otherButtonTitle != nil) {
UIAlertAction *otherButton = [UIAlertAction
actionWithTitle:otherButtonTitle
style:UIAlertActionStyleDefault
handler:^(UIAlertAction *action)
{
tapBlock(alertController, ALERTACTION_OTHER); // OTHER BUTTON CALL BACK ACTION
}];
[alertController addAction:otherButton];
}
[controller presentViewController:alertController animated:YES completion:nil];
return alertController;
}
#end
in your ViewController.m
[UIAlertController showAlertIn:self WithTitle:#"" message:#"" cancelButtonTitle:#"Cancel" otherButtonTitles:#"Other" tapBlock:^(UIAlertController *alertController, NSInteger index){
if(index == ALERTACTION_CANCEL){
// CANCEL BUTTON ACTION
}else
if(index == ALERTACTION_OTHER){
// OTHER BUTTON ACTION
}
[alertController dismissViewControllerAnimated:YES completion:nil];
}];
NOTE: If you want to add more than two buttons then add another
more UIAlertAction to the UIAlertController.
Use UIAlertController instead of UIAlertView
-(void)showMessage:(NSString*)message withTitle:(NSString *)title
{
UIAlertController * alert= [UIAlertController
alertControllerWithTitle:title
message:message
preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *okAction = [UIAlertAction actionWithTitle:#"OK" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action){
//do something when click button
}];
[alert addAction:okAction];
UIViewController *vc = [[[[UIApplication sharedApplication] delegate] window] rootViewController];
[vc presentViewController:alert animated:YES completion:nil];
}
I tried the above methods, and no one can show the alert view, only when I put the presentViewController: method in a dispatch_async sentence:
dispatch_async(dispatch_get_main_queue(), ^ {
[self presentViewController:alert animated:YES completion:nil];
});
Refer to Alternative to UIAlertView for iOS 9?.
-(void)showAlert{
UIAlertController* alert = [UIAlertController alertControllerWithTitle:#"Title"
message:#"Message"
preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction* defaultAction = [UIAlertAction actionWithTitle:#"OK" style:UIAlertActionStyleDefault
handler:^(UIAlertAction * action) {}];
[alert addAction:defaultAction];
[self presentViewController:alert animated:YES completion:nil];
}
[self showAlert]; // calling Method
Check this:
UIAlertController *alertctrl =[UIAlertController alertControllerWithTitle:#"choose Image" message:nil preferredStyle:UIAlertControllerStyleActionSheet];
UIAlertAction *camera =[UIAlertAction actionWithTitle:#"camera" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action) {
[self Action]; //call Action need to perform
}];
[alertctrl addAction:camera];
-(void)Action
{
}
UIAlertController * alert = [UIAlertController
alertControllerWithTitle:#"Are you sure you want to logout?"
message:#""
preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction* yesButton = [UIAlertAction
actionWithTitle:#"Logout"
style:UIAlertActionStyleDestructive
handler:^(UIAlertAction * action)
{
}];
UIAlertAction* noButton = [UIAlertAction
actionWithTitle:#"Cancel"
style:UIAlertActionStyleDefault
handler:^(UIAlertAction * action) {
//Handle no, thanks button
}];
[alert addAction:noButton];
[alert addAction:yesButton];
[self presentViewController:alert animated:YES completion:nil];