Custom alert view in iOS issue - ios

Question

In my app I've to create a custom alert view like the following:
So I followed this tutorial to create a custom alert view. I finished it but I'm getting issue in the following method:
- (void)addOrRemoveButtonWithTag:(int)tag andActionToPerform:(BOOL)shouldRemove {
NSMutableArray *items = [[NSMutableArray alloc]init];
[items addObject:self.buttonOk];
[items addObject:self.buttonClose];
int buttonIndex = (tag == 1);
if (shouldRemove) {
[items removeObjectAtIndex:buttonIndex];
} else {
if (tag == 1) {
[items insertObject:self.buttonOk atIndex:buttonIndex];
} else {
[items insertObject:self.buttonClose atIndex:buttonIndex];
}
}
}
I edited it than the tutorial because I don't need a UIToolBar for buttons. When I run the app it says me that I can't insert a nil object in an NSMutableArray, but I don't understand what's wrong, I hope you can help me to fix this issue.
UPDATE
Here's all the class code I developed:
#import "CustomAlertViewController.h"
#define ANIMATION_DURATION 0.25
#interface CustomAlertViewController ()
- (IBAction)buttonOk:(UIButton *)sender;
- (IBAction)buttonCancel:(UIButton *)sender;
#property (weak, nonatomic) IBOutlet UIButton *buttonClose;
#property (weak, nonatomic) IBOutlet UIButton *buttonOk;
#property (strong, nonatomic) IBOutlet UIView *viewAlert;
-(void)addOrRemoveButtonWithTag:(int)tag andActionToPerform:(BOOL)shouldRemove;
#end
#implementation CustomAlertViewController
- (id)init
{
self = [super init];
if (self) {
[self.viewAlert setFrame:CGRectMake(self.labelAlertView.frame.origin.x,
self.labelAlertView.frame.origin.y,
self.labelAlertView.frame.size.width,
self.viewAlert.frame.size.height)];
[self.buttonOk setTag:1];
[self.buttonClose setTag:0];
}
return self;
}
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view from its nib.
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (void)showCustomAlertInView:(UIView *)targetView withMessage:(NSString *)message {
CGFloat statusBarOffset;
if (![[UIApplication sharedApplication] isStatusBarHidden]) {
CGSize statusBarSize = [[UIApplication sharedApplication] statusBarFrame].size;
if (statusBarSize.width < statusBarSize.height) {
statusBarOffset = statusBarSize.width;
} else {
statusBarOffset = statusBarSize.height;
}
} else {
statusBarOffset = 0.0;
}
CGFloat width, height, offsetX, offsetY;
if ([[UIApplication sharedApplication] statusBarOrientation] == UIInterfaceOrientationLandscapeLeft ||
[[UIApplication sharedApplication] statusBarOrientation] == UIInterfaceOrientationLandscapeRight) {
width = targetView.frame.size.width;
height = targetView.frame.size.height;
offsetX = 0.0;
offsetY = -statusBarOffset;
}
[self.view setFrame:CGRectMake(targetView.frame.origin.x, targetView.frame.origin.y, width, height)];
[self.view setFrame:CGRectOffset(self.view.frame, offsetX, offsetY)];
[targetView addSubview:self.view];
[self.viewAlert setFrame:CGRectMake(0.0, -self.viewAlert.frame.size.height, self.viewAlert.frame.size.width, self.viewAlert.frame.size.height)];
[UIView beginAnimations:#"" context:nil];
[UIView setAnimationDuration:ANIMATION_DURATION];
[UIView setAnimationCurve:UIViewAnimationCurveEaseOut];
[self.viewAlert setFrame:CGRectMake(0.0, 0.0, self.viewAlert.frame.size.width, self.viewAlert.frame.size.height)];
[UIView commitAnimations];
[self.labelAlertView setText:#"CIAO"];
}
- (void)removeCustomAlertFromView {
[UIView beginAnimations:#"" context:nil];
[UIView setAnimationDuration:ANIMATION_DURATION];
[UIView setAnimationCurve:UIViewAnimationCurveEaseOut];
[self.viewAlert setFrame:CGRectMake(0.0, -self.viewAlert.frame.size.height, self.viewAlert.frame.size.width, self.viewAlert.frame.size.height)];
[UIView commitAnimations];
[self.view performSelector:#selector(removeFromSuperview) withObject:nil afterDelay:ANIMATION_DURATION];
}
- (void)removeCustomAlertFromViewInstantly {
[self.view removeFromSuperview];
}
- (BOOL)isOkayButtonRemoved {
if (self.buttonOk == nil) {
return YES;
} else {
return NO;
}
}
- (BOOL)isCancelButtonRemoved {
if (self.buttonClose == nil) {
return YES;
} else {
return NO;
}
}
- (void)removeOkayButton:(BOOL)shouldRemove {
if ([self isOkayButtonRemoved] != shouldRemove) {
[self addOrRemoveButtonWithTag:1 andActionToPerform:shouldRemove];
}
}
- (void)removeCancelButton:(BOOL)shouldRemove {
if ([self isCancelButtonRemoved] != shouldRemove) {
[self addOrRemoveButtonWithTag:0 andActionToPerform:shouldRemove];
}
}
- (void)addOrRemoveButtonWithTag:(int)tag andActionToPerform:(BOOL)shouldRemove {
NSMutableArray *items = [[NSMutableArray alloc]init];
[items addObject:self.buttonOk];
[items addObject:self.buttonClose];
int buttonIndex = (tag == 1);
if (shouldRemove) {
[items removeObjectAtIndex:buttonIndex];
} else {
if (tag == 1) {
[items insertObject:self.buttonOk atIndex:buttonIndex];
} else {
[items insertObject:self.buttonClose atIndex:buttonIndex];
}
}
}
- (IBAction)buttonOk:(UIButton *)sender {
[self.delegate customAlertOk];
}
- (IBAction)buttonCancel:(UIButton *)sender {
[self.delegate customAlertCancel];
}
#end
UPDATE 2
Code in which I use the CustomAlertView:
#import "PromotionsViewController.h"
#import "CustomAlertViewController.h"
#interface PromotionsViewController () <CustomAlertViewControllerDelegate> {
BOOL isDeletingItem;
}
#property(nonatomic,strong) CustomAlertViewController *customAlert;
- (IBAction)buttonBack:(UIButton *)sender;
#property (weak, nonatomic) IBOutlet UIButton *buttonAlert;
- (IBAction)buttonAlert:(UIButton *)sender;
#end
#implementation PromotionsViewController
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view.
[self.buttonAlert setTitle:self.promotionSelected forState:UIControlStateNormal];
[self.customAlert setDelegate:self];
isDeletingItem = NO;
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (IBAction)buttonBack:(UIButton *)sender {
[self dismissViewControllerAnimated:YES completion:nil];
}
- (IBAction)buttonAlert:(UIButton *)sender {
self.customAlert = [[CustomAlertViewController alloc]init];
[self.customAlert removeOkayButton:NO];
[self.customAlert removeCancelButton:NO];
NSString *message = [NSString stringWithFormat:#"La tua offerta %# del 20%% è stata convertita in punti IoSi x10", self.promotionSelected];
[self.customAlert showCustomAlertInView:self.view withMessage:message];
isDeletingItem = YES;
}
- (void)customAlertOk {
if (isDeletingItem) {
[self.customAlert removeCustomAlertFromViewInstantly];
} else {
[self.customAlert removeCustomAlertFromView];
}
}
- (void)customAlertCancel {
[self.customAlert removeCustomAlertFromView];
if (isDeletingItem) {
isDeletingItem = NO;
}
}
#end

Answer 1

Maybe you're calling addOrRemoveButtonWithTag:andActionToPerform: at a time where your UI is not fully created, since UI elements are created asynchronously. So if you call this method, right after custom alert view instanciation, you'll get your crash because the buttons in the view are not created.
To solve this issue, you need to call addOrRemoveButtonWithTag:andActionToPerform: only once your custom alert has been added to the view hierarchy.
EDIT :
With the example code you gave in edit 2, you call these lines :
- (IBAction)buttonAlert:(UIButton *)sender {
self.customAlert = [[CustomAlertViewController alloc]init];
[self.customAlert removeOkayButton:NO];
[self.customAlert removeCancelButton:NO];
}
but when you have just instantiated CustomAlertViewController, its 2 buttons are not yet created, so I suggest you add 2 properties hasOkButton and hasCancelButton and a new constructor to your custom class like this one :
- (instancetype) initWithOk:(BOOL)OkButton AndCancel:(BOOL) CancelButton
{
if(self = [super init])
{
hasOkButton = OkButton;
hasCancelButton = CancelButton;
}
}
-(void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
// At this time, the custom UI buttons will be created in the UI view hierarchy
[self removeOkayButton: hasOkButton];
[self removeOkayButton: hasCancelButton];
}
And in the caller you can use the following to display a custom alert View:
- (IBAction)buttonAlert:(UIButton *)sender {
self.customAlert = [[CustomAlertViewController alloc] initWithOk:NO AndCancel:NO];
// ...
}
EDIT #2
I tried your solution in a real project, I made it work by using these lines int the caller :
- (IBAction)buttonAlert:(UIButton *)sender {
self.customAlert = [self.storyboard instantiateViewControllerWithIdentifier:#"customAlertView"];
self.customAlert.hasOK = NO;
self.customAlert.hasCancel = YES;
NSString *message = [NSString stringWithFormat:#"La tua offerta %# del 20%% è stata convertita in punti IoSi x10", self.promotionSelected];
[self.customAlert showCustomAlertInView:self.view withMessage:message];
isDeletingItem = YES;
}
In the CustomAlertViewController declare 2 visible properties hasOK and hasCancel in.h.
And modify your .m by adding method :
-(void)viewWillAppear:(BOOL)animated
{
[self removeOkayButton:self.hasOK];
[self removeCancelButton:self.hasCancel];
}
Be sure to modify your storyboard (if eligible) to have the "customAlertView" defined this way :
Don't forget also to bind your UIButton to the controller this can be a mistake too in your implementation :
Hope this will help you :)

Answer 2

I found on the web a tutorial to create custom alert view by using code, if you are interested you can go to this tutorial. I used it for my issue and it worked great! You have to fix a few things, because it uses deprecated command but it's easy to fix it.
If you are interested just take a look about this tutorial. I think you can integrate it in your app and after you can easily use for other stuff if it's necessary. I hope that my answer will help someone.