iOS键盘弹出 视图向上滚动键盘高度
2017-04-11 本文已影响1738人
打瞌睡de小男孩
1.先添加对键盘的监听
[[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];
[[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];
当系统消息出现UIKeyboardWillShowNotification和UIKeyboardWillHideNotification消息就会调用我们的keyboardWillShow和keyboardWillHide方法。
2.实现监听方法
#pragma mark ---- 根据键盘高度将当前视图向上滚动同样高度
///键盘显示事件
- (void)keyboardWillShow:(NSNotification *)notification {
//获取键盘高度,在不同设备上,以及中英文下是不同的
CGFloat kbHeight = [[notification.userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size.height;
//计算出键盘顶端到inputTextView panel底端的距离(加上自定义的缓冲距离INTERVAL_KEYBOARD)
CGFloat offset = kbHeight;
// 取得键盘的动画时间,这样可以在视图上移的时候更连贯
double duration = [[notification.userInfo objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
//将视图上移计算好的偏移
if(offset > 0) {
[UIView animateWithDuration:duration animations:^{
self.view.frame = CGRectMake(0.0f, -offset, self.view.frame.size.width, self.view.frame.size.height);
}];
}
}
#pragma mark ---- 当键盘消失后,视图需要恢复原状
///键盘消失事件
- (void)keyboardWillHide:(NSNotification *)notify {
// 键盘动画时间
double duration = [[notify.userInfo objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
//视图下沉恢复原状
[UIView animateWithDuration:duration animations:^{
self.view.frame = CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height);
}];
}
3.注销通知
-(void)dealloc
{
[[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil];
[[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];
}
4.然后在这里安利一个很好的第三方 IQKeyboardManager 特别好用
有需要的可以直接去下载 https://github.com/hackiftekhar/IQKeyboardManager