Check if any textfield, textview or label changed for a UIViewController..? - iphone

Question

I have a view controller and it contains n number of UITextFields and UItextViews and UILabels, is there anyhow I can get notified if any of them changes..?
I can do it by manually looking at each of them in their respective TextDidChangeNotification and similar but I am looking for a more optimized way of doing this, where I don't have to worry about each of them .

Answer 1

// Assumes you don't use tag values now - if you do small change to create
// and index set, add the ones you use, so all new ones assigned are unique.
// assumes ARC
1) New ivar:
{
NSMutableDictionary *savedValues;
}
1) When you want to baseline the values:
savedValues = [self snapshot];
2) call this to baseline current values initially then at any later point:
- (NSMutableDictionary *)snapshot
{
NSInteger tag = 1;
NSMutableDictionary *dict = [NSMutableDictionary dictionaryWithCapacity:[self.view.subviews count]];
for(UIView *v in self.view.subviews) {
if([v isKindOfClass:[UILabel class]] || [v isKindOfClass:[UITextField class]] || [v isKindOfClass:[UITextView class]]) {
if(v.tag == 0) v.tag = tag++; // will happen once
// EDIT below
    [dict setObject:[NSString stringWithString:[(id)v text]] forKey:[NSNumber numberWithInteger:tag]];
}
}
return dict;
}
4) When you want to see if anything changed:
- (BOOL)anyChanges
{
NSDictionary *currentDict = [self snapshot];
return [currentDict isEqualToDictionary:savedValues];
}

Answer 2

You should use one method for all textFields, textView and Labels. and give a unique tag to textFields and textViews and labels. which help you for define it's textField ,textView or Label.
if(sender.tag == 1000)//UILabel
{
UILabel *label=(UILabel *)sender
//write own code for label what do you want.
}
else if(sender.tag == 2000)//UITextField
{
UITextField *textField=(UITextField *)sender
//write own code for textField what do you want.
}
else if(sender.tag == 3000)// UITextView
{
UITextView *textView=(UITextView *)sender
//write own code for textView what do you want.
}

Answer 3

Make your class to handle UIControlEventValueChanged event in your textfield, textview or label's value is changed. Add this line ViewDidLoad method:
[youLabel addTarget:self action:#selector(valueChanged:)
forControlEvents:UIControlEventValueChanged];
// add for textfield, textview also if needed
[youTextField addTarget:self action:#selector(valueChanged:)
forControlEvents:UIControlEventValueChanged];
[youTextView addTarget:self action:#selector(valueChanged:)
forControlEvents:UIControlEventValueChanged];
Now selector would be called when ever value is changed
- (void) valueChanged:(id)sender{
if(sender isKindofClass[UILabel class])
{
//label value changed here to differntiate used tag
if([sender tag] == 0)
....
....
}
else if(sender isKindofClass[UITextField class])
{
// textField value changed to differntiate used tag
if([sender tag] == 0)
....
....
}
else if(sender isKindofClass[UITextView class])
{
// textview value changed to differntiate used tag
if([sender tag] == 0)
....
....
}
}