使用keyboardWillShow的UITableView和UIView

Question

我有这个UITableView几乎填满了我的整个UIViewController,我在底部有一个包含按钮和文本字段的UIView.

当我单击文本字段时,我希望UIView和tableview向上推,这样UIView就在键盘顶部.

- UIView:  
  - UITextField
  - UIButton

我在这里尝试了多个建议,但似乎没有一个在我的情况下有用.

Answer 1

第1步:
制作底部约束的出口UIView

步骤2:
添加键盘显示和隐藏的观察者,然后根据键盘高度更改约束常量.

//**In viewDidLoad method** 

    // register for keyboard notifications
    [[NSNotificationCenter defaultCenter] addObserver:self 
                                             selector:@selector(keyboardWillShow:) 
                                                 name:UIKeyboardWillShowNotification 
                                               object:nil];
    // register for keyboard notifications
    [[NSNotificationCenter defaultCenter] addObserver:self 
                                             selector:@selector(keyboardWillHide:) 
                                                 name:UIKeyboardWillHideNotification 
                                               object:nil];  

第3步:
管理约束作为键盘显示和隐藏通知,如下所示

- (void)keyboardWillShow:(NSNotification *)notification
{

    NSDictionary* userInfo = [notification userInfo];

   // get the size of the keyboard
   CGSize keyboardSize = [[userInfo objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;

   CGSize keyboardSizeNew = [[userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;

  [UIView animateWithDuration:0.2
    animations:^{
        _bottomConstraintofView.constant = keyboardSizeNew.height;
        [self.view layoutIfNeeded]; // Called on parent view
    }];
 }

- (void)keyboardWillHide:(NSNotification *)notification
{
    [UIView animateWithDuration:0.2
    animations:^{
        _bottomConstraintofView.constant = 0;
        [self.view layoutIfNeeded]; 
    }];
}  

Swift中的解决方案

func keyboardWillShow(notification: NSNotification){
    let userInfo:NSDictionary = notification.userInfo!
    let keyboardSize:CGSize = userInfo.objectForKey(UIKeyboardFrameBeginUserInfoKey)!.CGRectValue().size

    let keyboardSizeNow:CGSize = userInfo.objectForKey(UIKeyboardFrameEndUserInfoKey)!.CGRectValue().size

    UIView.animateWithDuration(0.2, animations: { () -> Void in
        self.bottomConstraintofView.constant = keyboardSizeNow.height
        self.view.layoutIfNeeded()
    })
}

func keyboardWillHide(notification: NSNotification){
    UIView.animateWithDuration(0.2, animations: { () -> Void in
        self.bottomConstraintofView.constant = 0
        self.view.layoutIfNeeded()
    })
}