How do I limit characters in UITextView ? - iphone

Question

I have been looking for solutions and found the following piece of code. But I do not know how to use it, unfortunately.
- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)string {
NSUInteger newLength = [textField.text length] + [string length] - range.length;
return (newLength > 25) ? NO : YES;
}
Just for testing purposes I set up an IBACTION
-(IBAction)checkIfCorrectLength:(id)sender{
[self textView:myTextView shouldChangeTextInRange: ?? replacementText: ?? ];
}
What do I pass for shouldChangeTextInRange and replacementText ?
Or am I getting it completely wrong ?

Answer 1

Calling textView:shouldChangeTextInRange:replacementText: from checkIfCorrectLength: doesn't make sense. If you want to test the length from multiple methods, factor the test out into its own method:
- (BOOL)isAcceptableTextLength:(NSUInteger)length {
return length <= 25;
}
- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)string {
return [self isAcceptableTextLength:textField.text.length + string.length - range.length];
}
-(IBAction)checkIfCorrectLength:(id)sender{
if (![self isAcceptableTextLength:self.textField.text.length]) {
// do something to make text shorter
}
}

Answer 2

Hi I found and modified the code here. So for xamarin users. try the following:
textView.ShouldChangeText += delegate
{
if(textView.Text.Length > 159) // limit to one sms length
{
return false;
}
return true;
}

Answer 3

You don't call this method yourself, the text view calls it whenever it's about to change its text. Just set the text view's delegate property (e.g. to your view controller) and implement the method there.

Answer 4

If the current object is the delegate of the text view, then you can use the following snippet:
- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text
{
return weightTextView.text.length + text.length - range.length < 7;
}
This worked for me.

Answer 5

- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text
{
if([text length] == 0)
{
if([textView.text length] != 0)
{
return YES;
}
else {
return NO;
}
}
else if([[textView text] length] > your limit value )
{
return NO;
}
return YES;
}