按Tab键切换2段文字的焦点，哪段文字的焦点为true，则字体颜色变为红色。

import QtQuickWindow {width: 640height: 480visible: truetitle: qsTr("2.2 属性")Rectangle {Text {id: thislabeltext: qsTr("hello world")font.pixelSize: 20font.family: "Consolas"focus: truecolor: focus ? "black" : "red"x: 100; y:100KeyNavigation.tab: thatlabel}Text {id: thatlabeltext: qsTr("hello world")font.pixelSize: 20font.family: "Consolas"color: focus ? "black" : "red"x: 100; y:150KeyNavigation.tab: thislabelfocus: !thislabel.focus}}
}