Need help on bar button item in xcode

I have the weirdest issue today. I always use toolbar and bar button item button and never have problem. Here is the issue: I have view and the bottom has toolbar. In the toolbar, I create two bar button items which are 'back' button and 'next' button. For some reason, when i build into simulator or i开发者_StackOverflowphone, those buttons are not sensitive like before. On other words, the buttons do not really work. I found out that the half part (top) of the buttons are working when you touch it or use mouse cursor to click it. But the other half (down) of the buttons are not working at all. Anybody has this kind of issue?

Half of the toolbar means status bar's height. Double check your view's height and change according to your status bar.