为什么有些 QtQuick 控件有隐藏变量？

Question

这个问题实际上来自。 QtQuick 项的某些属性被隐藏，例如 TreeView 中的 __listView。我知道有一些复杂的 UI 组件基于其他一些基本组件。

Qt 提供了使用它的可访问性但没有在文档中提及它，这样的隐藏属性确实按预期工作得很好。那么为什么 Qt 隐藏属性呢？我要用吗？

Answer 1

这是Qt4中QML开头创建的约定，我们可以在这个link中找到，Qt5中似乎没有记录：

Private Properties

QML and JavaScript do not enforce private properties like C++. There is a need to hide these private properties, for example, when the properties are part of the implementation. As a convention, private properties begin with two underscore characters. For example, __area, is a property that is accessible but is not meant for public use. Note that QML and JavaScript will grant the user access to these properties.
 Item {
     id: component
     width: 40; height: 50
     property real __area: width * height * 0.5    //not meant for outside use
 }

为什么有些 QtQuick 控件有隐藏变量？

Why some QtQuick Controls have the hidden variable?

qt

qml

qt5

qtquick2

qtquickcontrols2