CODEWITHSUNDEEP
iosios-autolayoutautolayout
zedzhao
zedzhao

Reputation: 517

How to convert constraints to VFL

       NSLayoutConstraint *constraint = [NSLayoutConstraint constraintWithItem:label1 attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:label2 attribute:NSLayoutAttributeTop multiplier:1.0 constant:5];

I tried to write this code in VFL,but it seems the VFL only provide the NSLayoutFormatAlignAllTop property. So I can't set label1 is lower than label2 in 5 points.

I want to know if this constraint can't be written in VFL.

Upvotes: 0

Views: 347

Answers (1)

Ketan Parmar
Ketan Parmar

Reputation: 27438

You can do something like,

  NSArray *verticalConstraints1 =[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-20-[label1]-20-|" options:0 metrics:nil views:views];  // this set top and bottom vertical constraint

 NSArray *verticalConstraints1 =[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-20-[label1]" options:0 metrics:nil views:views];  // this will set only top

 NSArray *horizontalConstraints =[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-20-[label1]-20-[label2]-20-|" options:0 metrics:nil views:views]; //this will vertical constraint between two label and top and bottom to label1 and label2 respactively

You can refer this link for more details.

Update :

For example,

 |-[button1(button2)]-[button2]-|

This constraints means, button1 must be the same width as button2, they have a standard spacing between them, button1 is a standard spacing from the left edge of the superview, and button2 is a standard spacing from the right edge of the superview.

If here you take button1(button2/2) then it's mean it's half width of button2. If you need this scenario in height manner then just add V: before statement.

another examle,

  V:|-(==padding)-[imageView]->=0-[button]-(==padding)-|

This constraints mean,

  • The top of the image view must be padding points from the top of the superview

  • The bottom of the image view must be greater than or equal to 0 points from the top of the button

  • The bottom of the button must be padding points from the bottom of the superview.

     |[button(==200@750)]-[label]|

This constrains means, The button’s width should be 200 points, with a priority of 750.

      |-30.0@200-[label]

The label should be spaced 30 points from the left of the superview, with a priority of 200.

In short you can set any type of constraints in VFL format.

Refer this link as reference for more details!

Hope this will help :)

Upvotes: 2

Related Questions