我怎样才能绑定属性（例如枚举），以不同类型（例如每个枚举的图像）的一个组成部分的财产？ [英] How can I bind a property (e.g. an Enum) to a component property of a different type (e.g. an image for each Enum)?

问题描述

我继承了使用JGoodies数据绑定到域模型连接到GUI的项目。不过，也有，我发现这也导致了一些错误一些不一致的地方。

I have inherited a project that uses JGoodies Binding to connect the domain model to the GUI. However, there are some inconsistencies that I have found which also cause some bugs.

在这个具体的例子，该GUI是重新通过两个单选按钮和标签psented $ P $。根据选择了哪个按钮，标签应显示一定的图像。按钮被绑定到不同的枚举值，如：

In this concrete case, the GUI is represented by two radio buttons and a label. Depending on which button is selected, the label should display a certain image. The buttons are bound to different Enum values, like this:

AbstractValueModel enumSelectionModel = presentationModel.getModel("selection");

radioBtn1 = BasicComponentFactory.createRadioButton(enumSelectionModel,
        Selection.selection1, "");

radioBtn2 = BasicComponentFactory.createRadioButton(enumSelectionModel,
        Selection.selection2, "");

选择是绑定属性，而选择是枚举，这意味着当不同的按钮被改变，在我的模型的选属性设置为相应的枚举值。

"selection" is the bound property, and Selection is the Enum, which means that when a different button is changed, the selection property in my model is set to the corresponding Enum value.

我的问题是：我怎么能这个属性绑定到由标签显示的图像

这是我所看到的，JGoodies数据是极好的结合就像琴弦的东西文本字段，但在这种情况下，也应该有一个转变，其中一些决定逻辑枚举属性映射到图像。

From what I saw, JGoodies is excellent for binding things like strings to text fields, but in this case, there should also be a transformation, some logic which decides maps the enum property to the image.

推荐答案

好像我只是不得不采取绑定API中一探究竟。一个 AbstractConverter 正是我一直在寻找。

Seems like I just had to take a closer look in the Binding API. An AbstractConverter is exactly what I was looking for.

Bindings.bind((JComponent) pictureLabel, "icon", new EnumToIconConverter(enumSelectionModel));

的绑定方法绑定pictureLabel的图标，通过转换器描述的模型。该转换器看起来是这样的：

The bind method binds the pictureLabel's icon to the model described by the converter. The converter looks like this:

class EnumToIconConverter extends AbstractConverter {

    EnumToIconConverter(ValueModel subject) {
        super(subject);
    }

    @Override
    public Object convertFromSubject(Object enum) {
        return enum == Selection.selection1 ? image1 : image2;
    }

    @Override
    public void setValue(Object obj) {
        throw new UnsupportedOperationException("setValue makes no sense for this converter");
    }
}

的 convertFromSubject 的方法是从哪儿来枚举形象改造已经完成。我没有落实的setValue ，因为它使得在这种情况下，没有任何意义。图像无法改变自己的，我只是想更新一条路可走 - 从枚举属性图片

The convertFromSubject method is where the transformation from Enum to image is done. I didn't implement setValue because it makes no sense in this case. The image cannot change on its own, I only want updates to go one way - from the enum property to image.

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