i have a problem to set a background image on main window. i discovered that qt can use css to give some appearance. for my application i have created the image and put in into folder name image in source code folder. i have successfully code the css syntax
Qt Code: 
  1. QWidget#centralwidget { background-image: url(:/image/mainbg2.png); background-repeat: repeat-x; }
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when I click apply there nothing happen on my main window. my question here is does this thing work on the spot or we need to compile first to see the result?