Why is this code not updating my UITextField? - objective-c

Question

if (![value integerValue]) {
textField.text = [[NSString alloc] initWithFormat:#"%d", *x];
[slider setValue:(float)*x];
}
if ([value integerValue]>100) {
textField.text = [[NSString alloc] initWithFormat:#"255"];
[slider setValue:100.0];
}
if ([value integerValue]<0) {
textField.text = [[NSString alloc] initWithFormat:#"0"];
[slider setValue:0.0];
}
[textField setText:value];
The textfield's value remains the one typed in, ignoring when I set it to a new value.
Can someone please explain why?

Answer 1

[textField setText:value];
sets the UITextField value back to value.

Answer 2

You are overwriting the textField.text property at the end of your method, no matter if it was "corrected" under one of your case-descisions.
Check that last line within your original code and note that textField.text = xyz is semantically equal to [textField setText:xyz].
To fix your issue, use this corrected version of your code:
if (![value integerValue]) {
textField.text = [[NSString alloc] initWithFormat:#"%d", *x];
[slider setValue:(float)*x];
}
else if ([value integerValue]>100) {
textField.text = [[NSString alloc] initWithFormat:#"255"];
[slider setValue:100.0];
}
else if ([value integerValue]<0) {
textField.text = [[NSString alloc] initWithFormat:#"0"];
[slider setValue:0.0];
}
else {
textField.text = value;
}