Style QComboBox popup menu margin Qt 4

Question

After countless hours trying to style a QComboBox, I'm stuck with the top and bottom margin where the items are inserted.

I would like to either remove or apply a background-color to the popup menu top and bottom white spaces.

QComboBox screen http://img576.imageshack.us/img576/3402/screenshot20120130at144.png

I added a min-height to the QListView not to show top and bottom arrows. I also looked at the QComboBoxPrivate class in Qt sources but it seems that the top and bottom margins are hardcoded.

Thanks for your help.

Edited: This is my stylesheet so far

QComboBox {
    border: 1px solid rgb(95, 95, 95);
    border-radius: 3px;
    padding: 1px 18px 1px 3px;
    min-width: 6em;
    color: rgb(220, 220, 220);
    background-color: rgb(80, 80, 80);
    margin: 0 0 0 0;
}

QComboBox:editable {
    background: rgb(80, 80, 80);
}

QComboBox:!editable {
    background: qlineargradient(x1: 0, y1: 0, x2: 0, y2: 1,
                                  stop: 0 rgb(51, 51, 51), stop: 0.4 rgb(39, 39, 39),
                                  stop: 0.5 rgb(32,32,32), stop: 1.0 rgb(38,38,38));;
}

QComboBox::drop-down:editable {
}

QComboBox:!editable:on {
}

QComboBox::drop-down:editable:on {
}

QComboBox:on { /* shift the text when the popup opens */
    padding-top: 3px;
    padding-left: 4px;
    background-color: rgb(80, 80, 80);
}

QComboBox::drop-down {
    subcontrol-origin: padding;
    subcontrol-position: center right;
    width: 15px; 
    right:3px;
    border-top-right-radius: 3px; /* same radius as the QComboBox */
    border-bottom-right-radius: 3px;
    background:none;
}

QComboBox::down-arrow {
    image: url(:/images/arrow-down-inverted.png);
    height: 10px;
}

QComboBox::down-arrow:on { /* shift the arrow when popup is open */
    top: 1px;
    left: 1px;
}

QListView#comboListView {
    background: rgb(80, 80, 80);
    color: rgb(220, 220, 220);
    min-height: 90px;
    margin: 0 0 0 0;
}

QListView#comboListView::item {
    background-color: rgb(80, 80, 80);
}

QListView#comboListView::item:hover {
    background-color: rgb(95, 95, 95);
}

Answer 1

The solution I found to remove the white margin is to set the combobox to read-only.

QCombobox* choiceBox = new QCombobox;
choiceBox->lineEdit()->setReadOnly(true);

Answer 2

You need to customize the QAbstractItemView in the QComboBox:

QComboBox QAbstractItemView {
    margin-top: 0px;
    padding-bottom: 0px;
}

Answer 3

Try the following stylesheet:

QComboBox {
  margin-top: 0px;
  margin-bottom: 0px;
}

This should set the margins to 0. Also here is a qt reference to the stylesheets.