Game Programming Using Qt

Time for action – adding needles to the clock

The next step is to add the hour, minute, and second needles to the clock. Let's start by creating a new component called Needle in a file called Needle.qml (remember that component names and files representing them need to start with a capital letter):

import QtQuick 2.0

Rectangle {
  id: root

  property int value: 0
  property int granularity: 60
  property alias length: root.height
  width: 2
  height: parent.height/2
  radius: width/2
  antialiasing: true
  anchors.bottom: parent.verticalCenter
  anchors.horizontalCenter: parent.horizontalCenter
  transformOrigin: Item.Bottom
  rotation: 360/granularity * (value % granularity)
}

Needle is basically a rectangle anchored to the center of its parent by its bottom edge, which ...