当单击下面的区域时，导航栏按钮单击事件触发。

I am having navigation bar with custom view as right bar button item. Custom view has two buttons in it. But when i touch area below navigation bar on right side it fires button touch event. I have checked frames of buttons and view by changing background color all are set perfectly. I checked for default iOS apps like clock, calendar, setting, notes etc they all have same behaviour. Touching in red rectangle in screenshots(of default iOS calendar app.) fires touch event of button same is happening with my app too..I am having navigation bar with custom view