Where i can find Checkbox component in QML ?

[duc_bkav]

Hi everybody, i have read the code about checkbox in QML

CheckBox {
id: checkBox
text: "Check box text"
}
Text {
text: checkBox.checked ? "Checked" : "Unchecked"
font.pixelSize: platformStyle.fontSizeMedium
font.family: platformStyle.fontFamilyRegular
color: platformStyle.colorNormalLight
}

i use Qt 4.7, but the code doesn't work.
Is there any module that i have to add into program ???
Please help me , thank you so much ..