使用C ++对象Q_PROPERTY绑定复选框“checked”属性 [英] Binding Checkbox 'checked' property with a C++ object Q_PROPERTY

问题描述

我正在学习QtQuick，我正在使用C ++类和QML属性之间的数据绑定。

I'm learning QtQuick and I'm playing with data binding between C++ classes and QML properties.

在我的C ++对象模型中，我有两个属性： / p>

In my C++ object Model, I have two properties :

Q_PROPERTY(QString name READ getName WRITE setName NOTIFY nameChanged)
Q_PROPERTY(bool status READ getStatus WRITE setStatus NOTIFY statusChanged)

在我的.qml文件中：

And in my .qml file :

TextEdit {
    placeholderText: "Enter your name"
    text: user.name
}

Checkbox {
    checked: user.status
}

当我用 setName 从我的C ++代码，它会自动反映在视图中。
当我检查/取消选中复选框，或者当我从我的C ++代码调用 setStatus（）时，没有任何反应。看起来属性检查的复选框与 TextEdit 组件的行为不同。

When I change the user name with setName from my C++ code, it is automatically reflected in the view. When I check/uncheck the checkbox, or when I call setStatus() from my C++ code, nothing happens. It seems the property checked of checkboxes haven't the same behavior as TextEdit components.

我不想以声明方式绑定我的属性。不是Qt Quick支持属性绑定？

I don't want to bind my properties in a declarative way. Doesn't Qt Quick support property binding ?

感谢您的帮助。

推荐答案

如leemes指出，用户单击复选框将打破您创建的绑定。所以，不要创建绑定，而是直接连接到更改信号来处理get情况。使用onClicked处理set大小写。此解决方案还需要您在Component.onCompleted（）中初始化。例如...

As leemes points out, user clicking the check box breaks the binding you've created. So, don't create the binding, but instead connect to the change signal directly to handle the "get" case. Use "onClicked" to handle the "set" case. This solution requires you also initialize in Component.onCompleted(). For example...

CheckBox {
    id: myCheck
    onClicked: user.status = checked
    Component.onCompleted: checked = user.status
    Connections {
        target: user
        onStatusChanged: myCheck.checked = user.status
    }
}

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