QML属性绑定

Question

当上下文变量发生变化时，isOn属性是否也会在代码的下面进行修改？

property bool isOn: { 
    if(context === undefined) 
     return false; 
    return true 
} 

Answer 1

诀窍是，尝试一下：

import QtQuick 2.7 
import QtQuick.Controls 2.0 

ApplicationWindow { 
    id: appWindow 
    width: 500 
    height: 800 
    visible: true 

    property bool isOn: { 
     if(context === undefined) 
      return false; 
     return true 
    } 
    property var context 
    Button { 
     text: isOn 
     onClicked: (context ? context = undefined : context = 1) 
    } 
} 

提示：是