title: Hiding Qt widget and keeping widget space
body: <p>In a simple form I made a few buttons and put a horizontal layout. When mouse leaves the area one of the buttons, the last one, should be hidden. Using <code>button-&gt;hide()</code> it works, but all the buttons are rearranged by the layout manager. What I want is that all other buttons remain in their positions. I tried replacing the widget with a widget placeholder and swapping the button and placeholder <code>hide()</code>/<code>show()</code>, calling <code>placeholder-&gt;resize(button-&gt;size())</code>, but the layout manager doesn't respect the resize, and the placeholder is set with its minimum size. What is the best way to remove a widget and keep its space?</p>