demo地址:
https://github.com/weiman152/SwiftCustomInputView
很多应用都有评论功能，评论功能涉及到的问题主要就是两个：
1.键盘弹出的高度
2.动态改变textview的高度
剩下的就是一些动画了。
这里封装的主要是这两部分的实现，可以方便的调用，简单使用如下：
@IBAction func inputButtonAction(_ sender: UIButton) {
let view = CustomInputView.instance(superView: self.view)
view?.delegate = self
}
实现效果：
111.gif
image.png
image.png
image.png
image.png
主要代码：
//
// CustomInputView.swift
// CustomInputView
//
// Created by iOS on 2018/5/24.
// Copyright © 2018年 weiman. All rights reserved.
//
import UIKit
protocol CustomInputViewDelegate: NSObjectProtocol {
/// 发送
func send(text: String)
}
class CustomInputView: UIView {
weak var delegate: CustomInputViewDelegate?
@IBOutlet weak var textView: UITextView!
@IBOutlet weak var sendButton: UIButton!
@IBOutlet weak var bottomViewHeight: NSLayoutConstraint!
@IBOutlet weak var bottomViewBottom: NSLayoutConstraint!
/// 最大限制字数，默认是100
private var maxWords: Int = 300
/// 在textview不滚动的情况下，允许输入的最大行数，超过这个行数，就进行滚动
private var maxRows: Int = 6
private var oneLineHeight: CGFloat = 0
private var origialHeight: CGFloat = 0
override func awakeFromNib() {
super.awakeFromNib()
setup()
setupLayout()
setupNotification()
}
override init(frame: CGRect) {
super.init(frame: frame)
setup()
setupLayout()
setupNotification()
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
private func setup() {
backgroundColor = UIColor(white: 0.5, alpha: 0.3)
textView.layer.borderWidth = 1
textView.layer.borderColor = UIColor.hex("eeeeee").cgColor
textView.layer.cornerRadius = 20
textView.layer.masksToBounds = true
textView.delegate = self
textView.becomeFirstResponder()
// 这句话让光标不会因为圆角而被遮挡一块
textView.textContainerInset = UIEdgeInsets(top: 10, left: 5, bottom: 5, right: 5)
origialHeight = bottomViewHeight.constant
}
private func setupLayout() {
}
/// 通知
private func setupNotification() {
NotificationCenter.default.addObserver(
self,
selector: #selector(keyboardWillChange),
name: .UIKeyboardWillChangeFrame,
object: nil
)
}
}
/// 公有方法
extension CustomInputView {
/// 初始化
class func instance(superView: UIView) -> CustomInputView? {
let view = Bundle.main.loadNibNamed("CustomInputView", owner: nil, options: nil)?.last
guard let customView = view as? CustomInputView else {
return nil
}
superView.addSubview(customView)
customView.frame = superView.bounds
return customView
}
/// 消失
func dismiss() {
removeFromSuperview()
}
/// 设置背景颜色和透明度
func set(backgroundColor: String, alpha: CGFloat = 1.0) {
self.backgroundColor = .hex(backgroundColor, alpha: alpha)
}
/// 最大字数限制
func set(max: Int) {
self.maxWords = max
}
/// 在textview不滚动的情况下，允许输入的最大行数，超过这个行数，就进行滚动
/// 注意，不是最多输入的行数
func set(maxRows: Int) {
self.maxRows = maxRows
}
}
/// 私有方法
extension CustomInputView {
@IBAction func sendButtonAction(_ sender: UIButton) {
delegate?.send(text: textView.text)
}
@objc private func keyboardWillChange(_ notify: Notification) {
guard let userInfo = notify.userInfo else {
return
}
guard
let duration = userInfo[UIKeyboardAnimationDurationUserInfoKey] as?TimeInterval,
let curveRaw = userInfo[UIKeyboardAnimationCurveUserInfoKey] as? Int,
let curve = UIViewAnimationCurve(rawValue: curveRaw),
let endRect = userInfo[UIKeyboardFrameEndUserInfoKey] as? CGRect else {
return
}
handleKeyBoardFrame(duration: duration, curve: curve, endRect: endRect)
}
private func handleKeyBoardFrame(duration: TimeInterval,
curve: UIViewAnimationCurve,
endRect: CGRect) {
// 注意：endRect在第三方键盘上获取的时候会先后出现两个高度，所以设置高度的时候，不要把下面这句话放在动画里面执行，不然的话，第三方键盘会抖一下
self.bottomViewBottom.constant = endRect.height
UIView.animate(withDuration: duration, animations: { [weak self] in
self?.layoutIfNeeded()
}) { (_) in
}
}
private func handleBottomHeight(currentHeight: CGFloat, maxHeight: CGFloat) {
// 一行的高度
if oneLineHeight == 0 {
oneLineHeight = currentHeight
}
if currentHeight <= oneLineHeight {
bottomViewHeight.constant = origialHeight
} else {
if CGFloat(currentHeight) < maxHeight {
bottomViewHeight.constant = CGFloat(currentHeight)
} else {
bottomViewHeight.constant = maxHeight
}
}
UIView.animate(withDuration: 0.2) {
self.layoutIfNeeded()
}
}
private func handleTextHeight(textView: UITextView) {
// 一行的高度（居然还有这种方法，涨知识）
guard let lineHeight = textView.font?.lineHeight else {
return
}
// ceilf:向上取整
let textMaxHeight = ceilf(Float(lineHeight) * Float(maxRows))
// 最大高度,别忘了上下间距
let maxHeight: CGFloat = CGFloat(textMaxHeight) + extraSize().paddingTop + extraSize().paddingBottom + extraSize().marginTop + extraSize().marginBottom
let size = textView.sizeThatFits(CGSize(width: textView.bounds.width, height: CGFloat(MAXFLOAT)))
let currentHeight = CGFloat(ceilf(Float(size.height))) + extraSize().paddingTop + extraSize().paddingBottom + extraSize().marginTop + extraSize().marginBottom
handleBottomHeight(currentHeight: currentHeight, maxHeight: maxHeight)
}
private func extraSize() -> (paddingTop: CGFloat, paddingBottom: CGFloat, marginTop: CGFloat, marginBottom: CGFloat) {
let textTop: CGFloat = textView.textContainerInset.top
let textBottom: CGFloat = textView.textContainerInset.bottom
let textViewTop: CGFloat = 10
let textViewBottom: CGFloat = 10
return (textTop,textBottom,textViewTop,textViewBottom)
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
dismiss()
}
}
/// 代理方法
extension CustomInputView: UITextViewDelegate {
func textViewDidChange(_ textView: UITextView) {
// 判断输入是否超出规定长度
if let text = textView.text, text.count >= maxWords {
let result = text.prefix(maxWords)
textView.text = String(result)
return
}
if textView.text.count > 0 {
sendButton.isSelected = true
} else {
sendButton.isSelected = false
}
// 计算当前textview内容的高度，动态改变textview以及父view的高度
handleTextHeight(textView: textView)
}
}
/// UIColor的扩展
extension UIColor {
static func hex(_ string: String, alpha: CGFloat = 1.0) -> UIColor {
let scanner = Scanner(string: string)
scanner.scanLocation = 0
var rgbValue: UInt64 = 0
scanner.scanHexInt64(&rgbValue)
let r = (rgbValue & 0xff0000) >> 16
let g = (rgbValue & 0x00ff00) >> 8
let b = (rgbValue & 0x0000ff)
if #available(iOS 10.0, *) {
return UIColor(
displayP3Red: CGFloat(r) / 0xff,
green: CGFloat(g) / 0xff,
blue: CGFloat(b) / 0xff,
alpha: alpha
)
} else {
return UIColor(
red: CGFloat(r) / 0xff,
green: CGFloat(g) / 0xff,
blue: CGFloat(b) / 0xff,
alpha: alpha
)
}
}
}
是不是挺简单的？明白了不？
备注：有些属性是在xib上设置的，需要的话，可以下载demo。
祝开心。
