在封闭的textview中使用动态字体自动调整大小的视图

时间:2018-10-24 20:01:20

标签: ios swift uiview uitextview

所以这是我似乎无法在此处搜索找到匹配的案例。

我有一个小的UIView,其中包含一个UITextView,并且UIView需要在TextView周围自动调整大小,以便在另一个视图上进行呈现。基本上,TextView需要完全填充UIView,并且UIView的大小应足以容纳TextView。

TextView仅包含几个句子,该句子应保留在屏幕上,直到发生外部事件并且某些值发生更改为止。

当我使用固定大小的字体时,一切都很棒。

但是,嘿。。。我是一个老家伙,我的手机上的文字大小有点大。在我的设备上测试它可以显示我必须丢失的东西。

当在textview属性中使用动态字体样式“标题2”,并在TextView属性中启用“自动调整字体”,并且文本大于默认值时,好像我没有正确捕获在边框上创建新的边框时,TextView的大小(带有较大的文本)。它返回的值看起来很像较小的默认大小的文本值,而不是增大的文本大小。

代码在下面,该视图的类代码以及调用代码(在此处进行超级明确显示)。我想我要么错过了一些愚蠢的事情,例如在字体发生问题之后捕获大小,但是即使将此代码移至新函数并在控件完全绘制后显式调用它似乎也没有实现。

我希望这有道理。

谢谢。

呼叫代码:

let noWView:NoWitnessesYetView = (Bundle.main.loadNibNamed("NoWitnessesYetView", owner: nil, options: nil)!.first as! NoWitnessesYetView)
//if nil != noWView {
let leftGutter:CGFloat = 20.0
let bottomGutter:CGFloat = 24.0
let newWidth = self.view.frame.width - ( leftGutter + leftGutter )
let newTop = (eventMap.frame.minY + eventMap.frame.height) - ( noWView.frame.height + bottomGutter ) // I suspect here is the issue
// I suspect that loading without drawing is maybe not allowing 
// the fonts to properly draw and the 
// TextView to figure out the size...?
noWView.frame = CGRect(x: 20, y: newTop, width: newWidth, height: noWView.frame.height)
self.view.addSubview(noWView)
//}

类代码:

import UIKit
class NoWitnessesYetView: UIView {
    @IBOutlet weak var textView: EyeneedRoundedTextView!
    override func draw(_ rect: CGRect) {
        let newWidth = self.frame.width
        // form up a dummy size just to get the proper height for the popup
        let workingSize:CGSize = self.textView.sizeThatFits(CGSize(width: newWidth, height: CGFloat(MAXFLOAT)))
        // then build the real newSize value
        let newSize = CGSize(width: newWidth, height: workingSize.height)
        textView.frame.size = newSize
        self.textView.isHidden = false
    }
    override func awakeFromNib() {
        super.awakeFromNib()
        self.backgroundColor = UIColor.clear // .blue
        self.layer.cornerRadius = 10
    }
}

1 个答案:

答案 0 :(得分:0)

这种处理内容的完美方法来自:https://www.youtube.com/watch?v=0Jb29c22xu8

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        // let's create our text view
        let textView = UITextView()
        textView.frame = CGRect(x: 0, y: 0, width: 200, height: 100)
        textView.backgroundColor = .lightGray
        textView.text = "Here is some default text that we want to show and it might be a couple of lines that are word wrapped"

        view.addSubview(textView)

        // use auto layout to set my textview frame...kinda
        textView.translatesAutoresizingMaskIntoConstraints = false
        [
            textView.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor),
            textView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
            textView.trailingAnchor.constraint(equalTo: view.trailingAnchor),
            textView.heightAnchor.constraint(equalToConstant: 50)
            ].forEach{ $0.isActive = true }

        textView.font = UIFont.preferredFont(forTextStyle: .headline)

        textView.delegate = self
        textView.isScrollEnabled = false

        textViewDidChange(textView)
    }

}

extension ViewController: UITextViewDelegate {

    func textViewDidChange(_ textView: UITextView) {
        print(textView.text)
        let size = CGSize(width: view.frame.width, height: .infinity)
        let estimatedSize = textView.sizeThatFits(size)

        textView.constraints.forEach { (constraint) in
            if constraint.firstAttribute == .height {
                constraint.constant = estimatedSize.height
            }
        }
    }

}