iOS UIView背景在移动时变得透明

Question

Right now, I'm using autolayout to update the constraints of this view so that it gets shifted upwards when the keyboard shows. Here is the method:

- (void)keyboardWillShow:(NSNotification *)sender
{
    if ( [self.yelpSearchTextField isFirstResponder] || [self.timeTextField isFirstResponder] || [self.radiusTextField isFirstResponder] ) {
        CGRect frame = [sender.userInfo[UIKeyboardFrameEndUserInfoKey] CGRectValue];
        CGRect viewFrame = self.yelpSearchView.frame;
        self.keyboardHeightConstraint.constant = frame.size.height + viewFrame.size.height;
        [self.view layoutIfNeeded];
    }
}

It works fine, but for some reason, whenever the keyboard appears, the background of the view becomes transparent.

Before: http://imgur.com/Axg3b9c

After: http://imgur.com/WA1zgSL

Any ideas why this is happening?

Here is a picture of my constraints: http://imgur.com/YlfzwhA

Even weirder behavior! Take a look at this - if I move the starting position of the view like in this picture: http://imgur.com/0XKtLC1

Then when it moves up, only half the view seems to show up. What could this mean? http://imgur.com/dYddOLK

Answer 1

First reason: Your problem is in your notification method

- (void)keyboardWillShow:(NSNotification *)sender;

Sender is a uitextfield or uitextview and you set frame of yelpSearchView. I think the yelpSearchView background color is Clearcolor.

Second reason: In your design may have a problem. I see your constraints picture. just Put the search bar in a view and set frame of that view

Answer 2

Try to add height constraint for your view. I suppose, it don't clip subviews and height = 0.

Answer 3

self.keyboardHeightConstraint.constant = frame.size.height + viewFrame.size.height;

This was my problem! I have no idea why I was setting the bottom constraint to this - I only needed to set it to the frame.size.height. I was adding too much extra, so the view was getting pushed past the visible area. I changed it to

self.keyboardHeightConstraint.constant = frame.size.height;