最近在项目中需要解决苹果系统输入法遮挡输入框的问题,预期结果为:
- 若键盘弹出后会遮挡输入框,则输入框随键盘弹起上移,输入法切换时输入框始终保持在键盘上方;
- 若键盘弹出后不会遮挡输入框,但切换输入法后会遮挡输入框,则输入框需要在切换后上移,随后输入法切换时输入框始终保持在键盘上方。
一. 背景
开发环境:iOS14 + Xcode v12.0.1 + Swift5
设备:iPhoneSE(其他机型测试有效)
页面采用自动布局
二. 实现方式
1. 监听键盘变化,获取键盘高度
在viewWillAppear中添加键盘弹出、收起、frame变化的通知
NotificationCenter.default.addObserver(self,
selector: #selector(keyboardWillAppear),
name: UIResponder.keyboardWillShowNotification,
object: nil)
NotificationCenter.default.addObserver(self,
selector: #selector(keyboardHasAppear),
name: UIResponder.keyboardDidShowNotification,
object: nil)
NotificationCenter.default.addObserver(self,
selector: #selector(keyboardWillDisappear),
name: UIResponder.keyboardWillHideNotification,
object: nil)
NotificationCenter.default.addObserver(self,
selector: #selector(keyboardFrameDidChange),
name: UIResponder.keyboardDidChangeFrameNotification,
object: nil)
(附:iOS键盘通知 https://www.jianshu.com/p/6af9feb7f86f)
实现 keyboardWillAppear:
@objc
func keyboardWillAppear(noti: Notification) {
// 获得软键盘的高
let keyboardSize = (noti.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue
let keyboardHeight = keyboardSize?.height
// 计算输入框和软键盘的高度差
let rect = self.nickNameEditView.containerView
.convert(self.nickNameEditView.containerView.bounds,
to: self.view) // 将rect由rect所在视图转换到目标视图view中,返回在目标视图view中的rect
self.nameFieldBottomHeight = self.view.bounds.height - (rect.origin.y + rect.size.height)
self.deltaHeight = (keyboardHeight ?? 0) - self.nameFieldBottomHeight
if self.keyboardFlag == 0, self.deltaHeight > 0 {
// 键盘原来是收起的,且遮挡输入框
self.pageContainerView.transform = CGAffineTransform(a: 1, b: 0, c: 0, d: 1,
tx: 0, ty: -self.deltaHeight - 4)
self.transformDistance = -self.deltaHeight - 4
}
}
实现keyboardHasAppear:
@objc
func keyboardHasAppear() {
self.keyboardFlag = 1 // 键盘已弹出
}
留坑,后续待补充