出现iOS键盘时如何向上移动视图? [英] How to move view up when iOS keyboard appears?

问题描述

对于只有三个文本字段和提交按钮的登录屏幕，我希望在键盘出现时视图向上移动，以便在该字段未隐藏时也不会向上移出视图.

For a login screen with just three textfields and submit button, I want the view to move up when the keyboard appears just enough so that while the field is not hidden, it also does not move up out of view.

所需的移动量使得提交按钮位于键盘上方的固定距离.虽然可以通过将页面上的字段向上移动为键盘留出空间，但提交按钮仍处于隐藏状态

The amount of movement needed is such that the submit button is a fixed distance above the keyboard. While it is possible by moving the fields high up on the page to leave room for the keyboard, the submit button is still hidden

我尝试只添加以下内容:

I tried just adding the following:

-(void) viewWillAppear:(BOOL)Animated {
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];
    
}
- (void)viewWillDisappear:(BOOL)animated {
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];
}

这会将视图向上移动一个固定的量，但如此之大，以至于字段对于编辑不可见，即它们太高了.

This moves the view up a fixed amount but so much so that the fields are not visible for editing, i.e. they are too high up.

建议另一个 SO 答案:

Another SO answer suggested:

-(void)textFieldDidBeginEditing:(UITextField *)textField
{
    [self animateTextField:textField up:YES];
}

- (void)textFieldDidEndEditing:(UITextField *)textField
{
    [self animateTextField:textField up:NO];
}

-(void)animateTextField:(UITextField*)textField up:(BOOL)up
{
    const int movementDistance = -200; // tweak as needed
    const float movementDuration = 0.3f; // tweak as needed
    
    int movement = (up ? movementDistance : -movementDistance);
    
    [UIView beginAnimations: @"animateTextField" context: nil];
    [UIView setAnimationBeginsFromCurrentState: YES];
    [UIView setAnimationDuration: movementDuration];
    self.view.frame = CGRectOffset(self.view.frame, 0, movement);
    [UIView commitAnimations];
}

我不知道如何实现这一点.如果你只是保持原样，什么都不会发生.我想你应该用你的文本字段的名称重命名文本字段，但在这种情况下，你会为​​每个文本字段都这样做吗?我无法让它产生任何效果.

I can't figure out how to implement this. If you just leave it as is nothing happens. I guess you are supposed to rename textfield with the name of your textfield but in that case, would you do it for each of the textfields? I cannot get it to have any effect.

另一个建议是使用诸如 TPKeyboardAvoiding 之类的类别，但这需要一个我在这种情况下不需要的滚动视图.

Another suggestion is to use a category such as TPKeyboardAvoiding however this requires a scrollview that I do not need in this case.

2015 年有没有针对这个问题的直接解决方案?

Is there no straightforward solution in 2015 for this issue?

推荐答案

当用户开始输入时，以下动画会将您的视图(在本例中为 viewForLogin)移动 200 像素以上.当文本字段结束编辑时，视图将动画回到原始位置.不要忘记为文本字段设置代表.

The following animation will move your view (viewForLogin in this case) 200 pixels above when the user starts typing. The view will animate back to original position when the textfield ends editing. Do not forget to set the delegates for the textfields.

Swift 3

func textFieldDidBeginEditing(_ textField: UITextField) {
    UIView.animate(withDuration: 0.3, animations: {
        self.view.frame = CGRect(x:self.view.frame.origin.x, y:self.view.frame.origin.y - 200, width:self.view.frame.size.width, height:self.view.frame.size.height);

    })
}

func textFieldDidEndEditing(_ textField: UITextField) {
    UIView.animate(withDuration: 0.3, animations: {
        self.viewSupport.frame = CGRect(x:self.viewSupport.frame.origin.x, y:self.viewSupport.frame.origin.y + 200, width:self.viewSupport.frame.size.width, height:self.viewSupport.frame.size.height);

    })
}

目标 C

-(void)textFieldDidBeginEditing:(UITextField *)textField
{
    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDuration:.3];
    [UIView setAnimationBeginsFromCurrentState:TRUE];
    self.view.frame = CGRectMake(self.view.frame.origin.x, self.view.frame.origin.y -200., self.view.frame.size.width, self.view.frame.size.height);

    [UIView commitAnimations];


}


-(void)textFieldDidEndEditing:(UITextField *)textField
{
    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDuration:.3];
    [UIView setAnimationBeginsFromCurrentState:TRUE];
    self.view.frame = CGRectMake(self.view.frame.origin.x, self.view.frame.origin.y +200., self.view.frame.size.width, self.view.frame.size.height);

    [UIView commitAnimations];

}

这篇关于出现iOS键盘时如何向上移动视图?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！