To be written…
var button = QPushButton();
function doFade() {
var time = 4000;
var s = Mixxx.getValue("[[Master]]", "crossfader");
var e = -1.0;
if (s < 0.0) {
e = 1.0;
}
Mixxx.startFade("[[Master]]", "crossfader");
Mixxx.point(0, s);
Mixxx.point(time, e);
Mixxx.endFade();
}
button.text = "Crossfade";
button.clicked.connect(doFade);
button.show();