Xcode 将UIView底部空间约束设置为键盘高度

我是autolayout的忠实粉丝，但我一直在故事板中实现它

我有一个UIView，我希望底部空间约束位于键盘结束的位置

我已经定义了所有约束，有人能告诉我如何在代码中实现这个约束吗？以及如何根据特定的iDevice获取键盘高度值，并将其与约束匹配

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谢谢

像这样走出视野的底部限制

@property (weak, nonatomic) IBOutlet NSLayoutConstraint *constraintContainerBottom;

用这个

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
    [self setupKeyboard:YES];
}

- (void)viewWillDisappear:(BOOL)animated
{
    [super viewWillDisappear:animated];
    [self setupKeyboard:NO];
}

- (void)setupKeyboard:(BOOL)appearing
{
    if (appearing) {
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];
    }else{
        [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil];
        [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];
    }
}

- (void)keyboardWillShow:(NSNotification*)notification
{
    CGSize keyboardSize = [[[notification userInfo] objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;
    double duration = [[[notification userInfo] objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
    int curve = [[[notification userInfo] objectForKey:UIKeyboardAnimationCurveUserInfoKey] intValue];
    [UIView beginAnimations:@"keyboardShown" context:nil];
    [UIView setAnimationDuration:duration];
    [UIView setAnimationCurve:curve];

    self.constraintContainerBottom.constant = keyboardSize.height;
    [self.view layoutIfNeeded];

    [UIView setAnimationDelegate:self];
    [UIView commitAnimations];
}

- (void)keyboardWillHide:(NSNotification*)notification
{
    double duration = [[[notification userInfo] objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
    int curve = [[[notification userInfo] objectForKey:UIKeyboardAnimationCurveUserInfoKey] intValue];
    [UIView beginAnimations:@"keyboardHidden" context:nil];
    [UIView setAnimationDuration:duration];
    [UIView setAnimationCurve:curve];

    self.constraintContainerBottom.constant = 0;
    [self.view layoutIfNeeded];

    [UIView setAnimationDelegate:self];
    [UIView commitAnimations];
}

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@Akshay Kheveria链接没有意义。这里重复了。“constraint”不是NSLayoutConstraint IBOutlet的属性…？@nickjf89它取决于您的处理方式。它的解决方案很好。：）我认为这是可行的。它实际上是恒定的……我已经更新了答案。对不起，如果我太笨了……我如何将约束的IBOutlet设置为我的UIView？只需双击约束，然后在左窗格中选择一个约束。只需将其拖动到所需的类文件并设置名称。