How to position UIbuttons in a table like way flexibly? - ios

Question

I need to position UIButtons flexibly like this in a vertical list:
A
B
C
D
The issue is that it need to be flexible, like when B is missing it should look like:
A
C
D
So there should be no blank space but the UIButtons should move up
Now I position the UIButtons programmatically like this, but this is only possible in iOS7 if I turn Autolayout off
But this in turn now requires to position ALL other Elements - esp on the bottom of the screen - also programmatically, which I do not want to do.
How can I position the UIButtons in such a way WITHOUT having to programmatically position all other elements on the screen programmatically.
In Android there is the tablelayout or linearLayout which handles that automatically!
EDIT:
It's all a big pain, but this is how it works:
position all your btns nicely left aligned, under each other so you can see them nicely in IB. at this stage the vertical spacing does not matter since we delete all these constranints created by IB anyway and programmatically add the vertical spacing we want later
make sure now that there are only the constraints you want, and NO constraints created by IB that you do not want.
In particular remove all vertical spacing constraints between the btns you want to programmatically reposition. Add the constraints you DO want one by one with IB by clicking on "Add constraint" in the grey popup. After that do not touch your layout anymore - you can easily mess it up!
Use this code to reposition now A in relation to C for example. don't forget to set B invisible
UIView *superview = self.view;
NSMutableArray *mutableConstraintsArray =[[NSMutableArray alloc]init];
NSLayoutConstraint *constraint = [NSLayoutConstraint constraintWithItem:A
attribute:NSLayoutAttributeBottom
relatedBy:NSLayoutRelationEqual toItem:C
attribute:NSLayoutAttributeTop multiplier:1.0 constant:-20.0];//C is 20 points under A
[mutableConstraintsArray addObject:constraint];
for (int i = 0; i<mutableConstraintsArray.count; i++) {
[superview addConstraint:mutableConstraintsArray[i]];
}
I used mutableConstraintsArray here so I could add multuple constraints at this time!
Lot's of effort IMHO!
Please correct/improve if there is an easier way!
Thanks to matt for pointing me in the right direction.

Answer 1

Now I programmatically position the UIButtons programmatically like this, but this is only possible in iOS7 if I turn Autolayout off
That's not true. You can also programmatically work with autolayout constraints. Let's say the deleted button B has a constraint to the button above it, A, and a constraint to the button below it, C. When you delete B, make a constraint (programmatically) between A and C and add that constraint to their common superview. Done! C now moves into position, D moves into position, and the rest follows.

Answer 2

try doing programmatically:
for( i=1 ; i<[no of buttons you want to create]; i++)
{
button =[UIButton buttonWithType:UIButtonTypeRoundedRect];
button.frame = CGRectMake(5 , y + 30, 82, 82);
button.Tag= i;
[self.view addSubView: button];
}
Now it all depends on your input, that how many button you wan't there on screen, regarding frames, you can manipulate the logic in terms of x and y coordinates to adjust correct position. and also you can use each single button using their tags....
It would be nice if you put no of buttons in array then comparing i with count of that array.
I did this and was working fine.