Javafx：使用FXML的可重用集合 [英] Javafx: Reusable collections using FXML

问题描述

我想将一个集合绑定到FXML中的多个ChoiceBox。
然而我知道如何使用的唯一方法是：

I'd like to bind a single collection to multiple ChoiceBox's in FXML. However the only way I know how is using:

<ChoiceBox fx:id="cb00" prefWidth="150.0" GridPane.rowIndex="0" GridPane.columnIndex="0">
    <items>
        <FXCollections fx:id="test" fx:factory="observableArrayList">
            <String fx:value="1" />
            <String fx:value="2" />
            <String fx:value="3" />
            <String fx:value="4" />
            <String fx:value="5" />
            <String fx:value="6" />
            <String fx:value="7" />
            <String fx:value="8" />
            <String fx:value="9" />
        </FXCollections>
    </items>
</ChoiceBox>

是否可以在控制器中声明集合并在FXML中引用它而不是复制集合对于每个ChoiceBox？

Is it possible to declare the collection in the controller and refer to it in FXML instead of copying the collection for each ChoiceBox?

推荐答案

您可以在控制器中定义项目：

You can define the items in the controller:

public class Controller {

    private ListProperty<String> choiceBoxItems = new SimpleListProperty(FXCollections.observableArrayList());

    public Controller() {
        IntStream.range(1,10).mapToObj(i -> Integer.toString(i))
            .forEach(choiceBoxItems::add);
    }

    public ListProperty<String> choiceBoxItemsProperty() {
        return choiceBoxItems ;
    }

    public ObservableList<String> getChoiceBoxItems() {
        return choiceBoxItemsProperty().get() ;
    }

    public void setComboBoxItems(ObservableList<String> choiceBoxItems) {
        choiceBoxItemsProperty().set(choiceBoxItems) ;
    }

    // ...
}

然后（这没有经过测试，但我认为它会起作用）：

and then (this is not tested, but I think it will work):

<ChoiceBox fx:id="cb00" items="${controller.choiceBoxItems}" prefWidth="150.0" GridPane.rowIndex="0" GridPane.columnIndex="0">

参见表达式绑定。 （实际上没有记录控制器在FXML命名空间中可用，键控制器，但我认为使用它是安全的。）

See expression binding in the FXML documentation. (It's not actually documented that the controller is available in the FXML namespace with key controller, but I think it is safe to use this.)

您也可以使用 fx：define ：

You can also just define the list in the FXML using fx:define:

<fx:define>

    <FXCollections fx:id="choiceBoxItems" fx:factory="observableArrayList">
        <String fx:value="1"/>
        <String fx:value="2"/>
        <String fx:value="3"/>
        <!-- ... -->
    </FXCollections>

</fx:define>

然后在每个选择框中引用它：

and then refer to it in each choice box:

<ChoiceBox fx:id="cb00" items="${choiceBoxItems}" prefWidth="150.0" GridPane.rowIndex="0" GridPane.columnIndex="0">

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