Question

当键盘出现在文本字段上时，我有以下代码用于上下移动视图。

-(void)textFieldDidBeginEditing:(UITextField *)textField{
    NSLog(@"height before animation%f",self.view.frame.size.height);
    NSLog(@"%f",self.view.frame.size.height);
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:0.3];
    [self.view setFrame:CGRectMake(0,-216,320,460)];
    [UIView commitAnimations];
}

-(void)textFieldDidEndEditing:(UITextField *)textField{
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:0.3];
    [self.view setFrame:CGRectMake(0,0,320,460)];
    [UIView commitAnimations];
    NSLog(@"height after animation %f",self.view.frame.size.height);
    }

这是我在键盘出现然后编辑完成后得到的示例日志：

2014-01-21 11:00:51.194 Master-view[456:70b] height before animation 568.000000
2014-01-21 11:00:53.635 Master-view[456:70b] height after animation 460.000000

视图的高度似乎降低了，这使得屏幕的底部不可互动。为什么会这样？

视图正在向上移动并且正在下降而没有问题。在视觉上似乎没有区别。在升空之前存在的所有元素都在下降后存在。但是屏幕底部的元素（超出460.0的高度）并不难解决。

Answer 1

 -(void)textFieldDidBeginEditing:(UITextField *)textField{
NSLog(@"height before animation%f",self.view.frame.size.height);
NSLog(@"%f",self.view.frame.size.height);
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.3];
[self.view setFrame:CGRectMake(0,-216,320,self.view.frame.size.height)];
[UIView commitAnimations];

}

-(void)textFieldDidEndEditing:(UITextField *)textField{
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.3];
[self.view setFrame:CGRectMake(0,0,320,self.view.frame.size.height)];
[UIView commitAnimations];
NSLog(@"height after animation %f",self.view.frame.size.height);
}

我根据视图高度设置框架，你只需在按键开始时改变y位置，并在结束编辑时尝试将其设置回来这可能对你有所帮助

Answer 2

尝试更改

-(void)textFieldDidBeginEditing:(UITextField *)textField{
    NSLog(@"height before animation%f",self.view.frame.size.height);
    NSLog(@"%f",self.view.frame.size.height);
    CGRect viewFrame = self.view.frame;
    viewFrame.origin.y = -216;
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:0.3];
    [self.view setFrame:viewFrame];
    [UIView commitAnimations];
}

-(void)textFieldDidEndEditing:(UITextField *)textField{

     CGRect viewFrame = self.view.frame;
     viewFrame.origin.y = 0;
     [UIView beginAnimations:nil context:NULL];
     [UIView setAnimationDuration:0.3];
     [self.view setFrame:viewFrame];
     [UIView commitAnimations];
     NSLog(@"height after animation %f",self.view.frame.size.height);
}

Answer 3

我们使用NSNotification键盘将显示，键盘将隐藏。

我们使用键盘节目的添加通知并隐藏我们在viewWillAppear中添加通知并删除viewWillDisappear中的通知。

-(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];
}


-(void)keyboardWillShow {

    if (self.view.frame.origin.y >= 0)
    {
        [self setViewMovedUp:YES];
    }
    else if (self.view.frame.origin.y < 0)
    {
        [self setViewMovedUp:NO];
    }
}

-(void)keyboardWillHide {
    if (self.view.frame.origin.y >= 0)
    {
        [self setViewMovedUp:YES];
    }
    else if (self.view.frame.origin.y < 0)
    {
        [self setViewMovedUp:NO];
    }
}



-(void)setViewMovedUp:(BOOL)movedUp
{
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:0.3]; 

    CGRect rect = self.view.frame;
    if (movedUp)
    {

        rect.origin.y -= kOFFSET_FOR_KEYBOARD;
        rect.size.height += kOFFSET_FOR_KEYBOARD;
    }
    else
    {
        rect.origin.y += kOFFSET_FOR_KEYBOARD;
        rect.size.height -= kOFFSET_FOR_KEYBOARD;
    }
    self.view.frame = rect;

    [UIView commitAnimations];
}

IOS：执行动画时视图高度会降低

3 个答案: