Unable to add textfields vertically in iOS? - ios

Question

I have added some text fields through story board vertically.Below them i want to add more text fields programatically but it is always adding only one text field.
Below is the code used
int i;
self.main_view.translatesAutoresizingMaskIntoConstraints = NO;
self.scroll_view.translatesAutoresizingMaskIntoConstraints = NO;
for (i=0; i<[arr_customEdtTxt count]; i++)
{
JVFloatLabeledTextField *tf = [[JVFloatLabeledTextField alloc] initWithFrame:CGRectMake(25, y, 270, 27)];
tf.textColor = [UIColor blackColor];
tf.font = [UIFont fontWithName:#"Helvetica" size:14];
CustomEditText *custom=[arr_customEdtTxt objectAtIndex:i];
tf.placeholder=custom.field_name;
tf.textAlignment=NSTextAlignmentLeft;
previousTextfield=tf;
//add bottom border
[self addBorder:tf];
tf.translatesAutoresizingMaskIntoConstraints = NO;
[self.main_view addSubview:tf];
y=y+27;
[self.main_view addConstraint:[NSLayoutConstraint constraintWithItem:tf attribute:NSLayoutAttributeCenterX relatedBy:NSLayoutRelationEqual toItem:self.main_view attribute:NSLayoutAttributeCenterX multiplier:1.0 constant:0] ];
[self.main_view addConstraint:[ NSLayoutConstraint constraintWithItem:tf
attribute:NSLayoutAttributeHeight
relatedBy:NSLayoutRelationEqual
toItem:nil
attribute:NSLayoutAttributeHeight
multiplier:1.0
constant:27.0]];
[self.main_view addConstraint:[ NSLayoutConstraint constraintWithItem:tf
attribute:NSLayoutAttributeWidth
relatedBy:NSLayoutRelationEqual
toItem:self.txt_email
attribute:NSLayoutAttributeWidth
multiplier:1.0
constant:0]];
if(i==0)
{
[self.main_view addConstraint:[NSLayoutConstraint constraintWithItem:tf attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:self.txt_exprience attribute:NSLayoutAttributeBottom multiplier:1 constant:15.0f]];
}
else
{
[self.main_view addConstraint:[NSLayoutConstraint constraintWithItem:tf attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:previousTextfield attribute:NSLayoutAttributeBottom multiplier:1 constant:15.0f]];
}
[arr_tf addObject:tf];
}
[self.main_view layoutIfNeeded];
[self setDatatoFields];
I am getting constraint error i want to add more text fields below the current text fields.Please tell how can i add more and more text fileds below

Answer 1

It looks like previousTextfield and tf refer to the same textfield in this line:
[self.main_view addConstraint:[NSLayoutConstraint constraintWithItem:tf attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:previousTextfield attribute:NSLayoutAttributeBottom multiplier:1 constant:15.0f]];
Also I noticed that at the end you add the textField to arr_tf but you also have arr_customEdtTxt depending on which one is your array of textFields you should change previousTextfield = tf with:
if(i > 0){
//Change arr_tf for arr_customEdtTxt if that is your array
previousTextfield = [arr_tf objectAtIndex:i-1];
}