在iOS点击输入框时，为了避免输入框被键盘覆盖，可以让输入框所在的控件往上移动。
Swift 3代码示例
func animateTextField(textField: UITextField, up: Bool)
{
let movementDistance:CGFloat = -130
let movementDuration: Double = 0.3
var movement:CGFloat = 0
if up
{
movement = movementDistance
}
else
{
movement = -movementDistance
}
UIView.beginAnimations("animateTextField", context: nil)
UIView.setAnimationBeginsFromCurrentState(true)
UIView.setAnimationDuration(movementDuration)
self.view.frame = self.view.frame.offsetBy(dx: 0, dy: movement)
UIView.commitAnimations()
}
func textFieldDidBeginEditing(textField: UITextField)
{
self.animateTextField(textField: textField, up:true)
}
func textFieldDidEndEditing(textField: UITextField)
{
self.animateTextField(textField: textField, up:false)
}
使用方法是：调用self.animationTextField() 来设置让文本框是否向上移动。
Swift 2代码示例
func animateTextField(textField: UITextField, up: Bool)
{
let movementDistance:CGFloat = -130
let movementDuration: Double = 0.3
var movement:CGFloat = 0
if up
{
movement = movementDistance
}
else
{
movement = -movementDistance
}
UIView.beginAnimations("animateTextField", context: nil)
UIView.setAnimationBeginsFromCurrentState(true)
UIView.setAnimationDuration(movementDuration)
self.view.frame = CGRectOffset(self.view.frame, 0, movement)
UIView.commitAnimations()
}
func textFieldDidBeginEditing(textField: UITextField)
{
self.animateTextField(textField, up:true)
}
func textFieldDidEndEditing(textField: UITextField)
{
self.animateTextField(textField, up:false)
}