Question

I know the ARC in iOS 5 but I’m now developing pre-iOS 5 code style, and want to solve this problem by a manual release approach.

My only goal for this is to make a very handy custom alert view with UITextField.

I have a ‘BigView’ view that has many functions in it. And it can possibly generate many UIAlertView for many different situation on the display with that view. So I know the way use UIAlertViewDelegate for each alert view, but kind of experimentally try want to make this as like UIButton’s ‘addTarget'(actually it’s UIControl’s method).

Briefly,

This is in the part of ‘BigView’ class and my ‘TextAlert’ instance fired by a button for email gathering .

BigView.m

- (void)emailFeedback:(id)sender
{
    TextAlert *textAlert = [[TextAlert alloc] initWithTitle:@"Enter your email address"];
    [textAlert setTarget:self action:@selector(textAlertInputed:)];
//    [textAlert release];
}

- (void)textAlertInputed:(NSString *)text
{
    NSLog(@"text alert inputed, text: %@", text);
}

and these are full my TextAlert files.

TextAlert.h

#import <Foundation/Foundation.h>

@interface TextAlert : NSObject <UIAlertViewDelegate>
{
    UIAlertView *alertView;
    UITextField *textField;
    id target;
    SEL action;
}

- (id)initWithTitle:(NSString *)title;
- (void)setTarget:(id)target action:(SEL)action;

@end

TextAlert.m

#import "TextAlert.h"

@implementation TextAlert

- (id)initWithTitle:(NSString *)title
{
    if (self = [super init]) 
    {
        alertView = [[UIAlertView alloc] initWithTitle:title message:@"beneath" delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles:@"OK", nil];
        textField = [[UITextField alloc] initWithFrame:CGRectMake(12, 45, 260, 25)];
        CGAffineTransform myTransform = CGAffineTransformMakeTranslation(0, 60);
        [alertView setTransform:myTransform];
        [textField setBackgroundColor:[UIColor whiteColor]];
        [alertView addSubview:textField];
        [alertView show];

    }
    return self;
}

- (void)dealloc
{
    [alertView release]; alertView = nil;
    [textField release]; textField = nil;
    [super dealloc];
}

- (void)setTarget:(id)_target action:(SEL)_action
{
    target = _target;
    action = _action;
}

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
    [target performSelector:action withObject:textField.text];
}

@end

So my main problem is the releasing point of TextAlert instance in the ‘BigView’ as you can see the only comment part full codes above. Of course if I remove that comment out, I got crash for call for method of deallocated.

And I also get error make textAlert instance as autoreleased one.

For me, the only solution for this is to make the ‘textAlert’ object in the ‘BigView’ a member of ‘BigView’ not local object. But in that case, my initial goal for handy and lightweight approach for this is not satisfied, I think. And the ‘BigView’ has already many member instances so I don’t want to add any more.

So any suggestions? Or It will be welcome any comment for this trying. I’m ready to hear any
reproves to my insufficient code, really.

Thanks in advance,

MK

Answer 1

This isn’t directly what you asked for, but could help you anyway.

Handling multiple UIAlertViews in a single UIViewController can be painful. When I ran into this problem, I found an alternative control on github, called BlockAlertsAndActionSheets. It uses blocks instead of delegates, the appearance can be fully customized (even to the default Apple-style) and there is also an “AlertView with an UITextField”. Works good for me and I didn’t have to reinvent that wheel! 😉