Question

我对自动布局有零知识，在视图中我有一个高度为115，宽度为320的UITextView，如果我在阵列中有一些图像，那么我将textview高度设置为50到60并在textView下面显示图像，我正在尝试设置为 NSLayoutConstraint ，但我无法更改textview的高度。请给我解决方案，这是我的代码

首先我试试这个

@IBOutlet var txt_description: UITextView!
     override func viewWillAppear(animated: Bool) {
    self.view.addConstraint(NSLayoutConstraint(item: txt_description, attribute: .Top, relatedBy: .Equal, toItem: view_of_segment, attribute: .Top, multiplier: 1, constant:10))
    }

第二是

 override func viewWillAppear(animated: Bool) {
  NSLayoutConstraint.activateConstraints([
            NSLayoutConstraint(item: txt_description, attribute: .Top, relatedBy: .Equal, toItem: txt_title, attribute: .Top, multiplier: 1.0, constant: 24),
            NSLayoutConstraint(item: txt_description, attribute: .Left, relatedBy: .Equal, toItem: txt_title, attribute: .Left, multiplier: 1.0, constant: 0),
            NSLayoutConstraint(item: txt_description, attribute: .Width, relatedBy: .Equal, toItem: txt_title, attribute: .Width, multiplier: 1.0, constant: 0),
            NSLayoutConstraint(item: txt_description, attribute: .Height, relatedBy: .Equal, toItem: nil, attribute: .NotAnAttribute, multiplier: 1.0, constant:4)
            ])


}

第三我试试这个

@IBOutlet var EqualHeight_txt_des: NSLayoutConstraint!
@IBOutlet var txt_description: UITextView!

override func viewWillAppear(animated: Bool) {
        super.viewWillAppear(animated);
 let leftiPadWidth:CGFloat = 50
        txt_description.setTranslatesAutoresizingMaskIntoConstraints(false)
       EqualHeight_txt_des.constant = leftiPadWidth
    }

请给我解决方案我无法改变textview的高度请分享您的宝贵知识

Swift In Autolayout TextView NSLayoutConstraint未更改，Textview Dynamic的高度更改

0 个答案: