键盘通知

n键盘状态改变的时候,系统会发出一些特定的通知
ØUIKeyboardWillShowNotification // 键盘即将显示
ØUIKeyboardDidShowNotification //键盘显示完毕
ØUIKeyboardWillHideNotification // 键盘即将隐藏
ØUIKeyboardDidHideNotification // 键盘隐藏完毕
ØUIKeyboardWillChangeFrameNotification // 键盘的位置尺寸即将发生改变
ØUIKeyboardDidChangeFrameNotification //键盘的位置尺寸改变完毕



n系统发出键盘通知时,会附带一下跟键盘有关的额外信息(字典),字典常见的key以下:
ØUIKeyboardFrameBeginUserInfoKey // 键盘刚开始的frame
ØUIKeyboardFrameEndUserInfoKey // 键盘最终的frame(动画执行完毕后)
ØUIKeyboardAnimationDurationUserInfoKey // 键盘动画的时间
ØUIKeyboardAnimationCurveUserInfoKey // 键盘动画的执行节奏(快慢)

 

/*
 UIKeyboardAnimationCurveUserInfoKey = 7; // 动画执行的节奏
 UIKeyboardAnimationDurationUserInfoKey = "0.25"; 键盘弹出/隐藏的动画所须要的时间
 UIKeyboardBoundsUserInfoKey = "NSRect: {{0, 0}, {320, 216}}”;//键盘的bounds
 UIKeyboardCenterBeginUserInfoKey = "NSPoint: {160, 588}”;//键盘准备弹出时的X,Y的中心坐标
 UIKeyboardCenterEndUserInfoKey = "NSPoint: {160, 372}”;//键盘弹出后的X,Y的中心坐标
 
 // 键盘弹出刚开始的那一刻的frame
 UIKeyboardFrameBeginUserInfoKey = "NSRect: {{0, 480}, {320, 216}}";
 // 弹出完毕的时候，键盘的frame
 UIKeyboardFrameEndUserInfoKey = "NSRect: {{0, 264}, {320, 216}}";
 
 // 键盘退出的frame
 // 键盘刚要退出那一刻的frame
 UIKeyboardFrameBeginUserInfoKey = "NSRect: {{0, 264}, {320, 216}}";
 // 键盘退出完毕那一刻的frame
 UIKeyboardFrameEndUserInfoKey = "NSRect: {{0, 480}, {320, 216}}";

 */