Java 在ListView中自定义单元格

我已经学习了如何自定义listview的单元格的教程，它的结构是在FXML中定义的。我像往常一样定义cellFactory：

setCellFactory（（ListView studentListView）->new-SwatchCell（））

使用定义如下的SwatchCell类：

package ui;

import java.io.*;
import javafx.fxml.*;
import javafx.scene.control.*;
import javafx.scene.layout.*;
import javafx.scene.shape.*;
import logic.*;

public class SwatchCell extends ListCell<ColorSwatch>{

private FXMLLoader fxmlLoader;
@FXML private Label name, tagLine;
@FXML private Circle color1, color2, color3, color4, color5;
@FXML private VBox cellRootNode;

@Override
protected void updateItem(ColorSwatch item, boolean empty) {
    super.updateItem(item, empty);

    if (empty || item == null) {
        setText(null);
        setGraphic(null);
    } else {
        if (fxmlLoader == null) {
            loadFXML();
        }
        name.setText(item.getName());
        String tl = "";

        for (Tag t : item.getTagLine()) {
            if ("".equals(tl)) {
                tl += t.getDescription();
            } else {
                tl += ", " + t.getDescription();
            }
        }

        this.tagLine.setText(tl);

        color1.setFill(item.getColors()[0]);
        color2.setFill(item.getColors()[1]);
        color3.setFill(item.getColors()[2]);
        color4.setFill(item.getColors()[3]);
        color5.setFill(item.getColors()[4]);

        setText(null);
        setGraphic(cellRootNode);
    }
}

private void loadFXML() {
    fxmlLoader = new FXMLLoader(getClass().getResource("SwatchCellGraph.fxml"));
    fxmlLoader.setController(this);
    try {
        cellRootNode = fxmlLoader.load();
    } catch (IOException e) {
        System.err.println("failed to load Cell FXML");
        System.exit(0);
    }
}
}

。我希望我包括了所有相关的代码

我要诚实地说，我不完全理解回调和CellFactory是如何详细工作的，这是我第一次以这种方式改变列表单元格。尽管我知道我不应该问“为我解决这个问题”，但对我来说，学习东西的最好方法是学习工作实例。很明显，我想让ListView的单元格采用FXML文件的外观。谢谢你的帮助

PS：所有FXML代码都是在场景生成器中生成的，不会在NetBeans中弹出任何错误，因此在语法上应该是良好的。FX：应该正确分配ID

主窗口的FXML：

    <?xml version="1.0" encoding="UTF-8"?>

<?import javafx.geometry.Insets?>
<?import javafx.geometry.Rectangle2D?>
<?import javafx.scene.control.Button?>
<?import javafx.scene.control.ComboBox?>
<?import javafx.scene.control.ListView?>
<?import javafx.scene.control.Separator?>
<?import javafx.scene.image.Image?>
<?import javafx.scene.image.ImageView?>
<?import javafx.scene.layout.HBox?>
<?import javafx.scene.layout.StackPane?>
<?import javafx.scene.layout.VBox?>

<StackPane fx:id="background" maxHeight="1.7976931348623157E308" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="550.0" prefWidth="275.0" stylesheets="@MainWindowCSS.css" xmlns="http://javafx.com/javafx/8.0.171" xmlns:fx="http://javafx.com/fxml/1" fx:controller="ui.MainWindowGraphController">
   <padding>
      <Insets bottom="10.0" left="10.0" right="10.0" top="10.0" />
   </padding>
   <children>
      <VBox fx:id="content" alignment="TOP_CENTER" maxHeight="1.7976931348623157E308" maxWidth="-Infinity" prefWidth="265.0" spacing="5.0">
         <children>
            <HBox prefHeight="32.0" prefWidth="200.0" spacing="5.0">
               <children>
                  <ImageView fitHeight="34.0" fitWidth="170.0" pickOnBounds="true" preserveRatio="true">
                     <image>
                        <Image url="@../resources/header.png" />
                     </image>
                     <viewport>
                        <Rectangle2D height="32.0" width="170.0" />
                     </viewport>
                  </ImageView>
                  <Button fx:id="miniButton" contentDisplay="GRAPHIC_ONLY" maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" mnemonicParsing="false" onAction="#minimize" prefHeight="32.0" prefWidth="32.0" styleClass="util-button" text="_">
                     <graphic>
                        <ImageView fitHeight="32.0" fitWidth="32.0" pickOnBounds="true" preserveRatio="true">
                           <image>
                              <Image url="@../resources/minimize.png" />
                           </image>
                        </ImageView>
                     </graphic>
                     <padding>
                        <Insets bottom="-5.0" left="-5.0" right="-5.0" top="-5.0" />
                     </padding>
                  </Button>
                  <Button fx:id="closeButton" contentDisplay="GRAPHIC_ONLY" maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" mnemonicParsing="false" onAction="#kill" prefHeight="32.0" prefWidth="32.0" styleClass="util-button" text="x">
                     <graphic>
                        <ImageView fitHeight="32.0" fitWidth="32.0" pickOnBounds="true" preserveRatio="true">
                           <image>
                              <Image url="@../resources/cross.png" />
                           </image>
                        </ImageView>
                     </graphic>
                     <padding>
                        <Insets bottom="-5.0" left="-5.0" right="-5.0" top="-5.0" />
                     </padding>
                  </Button>
               </children>
            </HBox>
            <Separator maxHeight="0.0" minHeight="0.0" prefHeight="0.0" prefWidth="177.0" />
            <ComboBox fx:id="comboBox" focusTraversable="false" maxWidth="1.7976931348623157E308" onAction="#repopulateListView" prefHeight="33.0" prefWidth="284.0" VBox.vgrow="ALWAYS" />
            <HBox spacing="5.0">
               <children>
                  <Button fx:id="addButton" contentDisplay="RIGHT" maxWidth="1.7976931348623157E308" mnemonicParsing="false" prefHeight="33.0" prefWidth="59.0" text="Add" HBox.hgrow="ALWAYS">
                     <graphic>
                        <ImageView fitHeight="14.0" fitWidth="14.0" pickOnBounds="true" preserveRatio="true">
                           <image>
                              <Image url="@../resources/add.png" />
                           </image>
                           <viewport>
                              <Rectangle2D height="14.0" width="14.0" />
                           </viewport>
                        </ImageView>
                     </graphic>
                  </Button>
                  <Button fx:id="editButton" contentDisplay="RIGHT" maxWidth="1.7976931348623157E308" mnemonicParsing="false" prefHeight="33.0" prefWidth="54.0" text="Edit" HBox.hgrow="ALWAYS">
                     <graphic>
                        <ImageView fitHeight="14.0" fitWidth="14.0" pickOnBounds="true" preserveRatio="true">
                           <image>
                              <Image url="@../resources/edit.png" />
                           </image>
                           <viewport>
                              <Rectangle2D height="14.0" width="14.0" />
                           </viewport>
                        </ImageView>
                     </graphic>
                  </Button>
                  <Button fx:id="deleteButton" contentDisplay="RIGHT" maxWidth="1.7976931348623157E308" mnemonicParsing="false" prefHeight="33.0" prefWidth="73.0" text="Delete" HBox.hgrow="ALWAYS">
                     <graphic>
                        <ImageView fitHeight="14.0" fitWidth="14.0" pickOnBounds="true" preserveRatio="true">
                           <image>
                              <Image url="@../resources/remove.png" />
                           </image>
                           <viewport>
                              <Rectangle2D height="14.0" width="14.0" />
                           </viewport>
                        </ImageView>
                     </graphic>
                  </Button>
               </children>
            </HBox>
            <Separator maxHeight="0.0" minHeight="0.0" prefHeight="0.0" prefWidth="177.0" />
            <ListView fx:id="itemListView" prefHeight="397.0" prefWidth="216.0" VBox.vgrow="ALWAYS" />
         </children>
         <padding>
            <Insets bottom="5.0" left="5.0" right="5.0" top="5.0" />
         </padding></VBox>
   </children>
</StackPane>

样本单元格的FXML：

    <?xml version="1.0" encoding="UTF-8"?>

<?import javafx.geometry.Insets?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.image.Image?>
<?import javafx.scene.image.ImageView?>
<?import javafx.scene.layout.HBox?>
<?import javafx.scene.layout.StackPane?>
<?import javafx.scene.layout.VBox?>
<?import javafx.scene.shape.Circle?>
<?import javafx.scene.text.Font?>

<VBox fx:id="cellRootNode" maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="107.0" prefWidth="255.0" spacing="5.0" style="-fx-background-color: #191919;" stylesheets="@MainWindowCSS.css" xmlns="http://javafx.com/javafx/8.0.171" xmlns:fx="http://javafx.com/fxml/1">
   <children>
      <Label fx:id="name" maxWidth="1.7976931348623157E308" text="ColorSwatch Name" textFill="WHITE" VBox.vgrow="ALWAYS" />
      <Label fx:id="tagLine" maxWidth="1.7976931348623157E308" text="TagLine" textFill="#b3b3b3">
         <graphic>
            <ImageView fitHeight="21.0" fitWidth="21.0" pickOnBounds="true" preserveRatio="true">
               <image>
                  <Image url="@../resources/tag.png" />
               </image>
            </ImageView>
         </graphic>
         <font>
            <Font size="12.0" />
         </font>
      </Label>
      <HBox prefHeight="12.0" prefWidth="64.0" spacing="5.0" VBox.vgrow="NEVER">
         <children>
            <StackPane minHeight="-Infinity" minWidth="-Infinity" prefHeight="44.0" prefWidth="44.0" styleClass="swatchBackground" HBox.hgrow="NEVER">
               <children>
                  <Circle fx:id="color1" fill="DODGERBLUE" radius="15.0" stroke="#ffffff00" strokeType="INSIDE" />
               </children>
            </StackPane>
            <StackPane minHeight="-Infinity" minWidth="-Infinity" prefHeight="44.0" prefWidth="44.0" styleClass="swatchBackground">
               <children>
                  <Circle fx:id="color2" fill="DODGERBLUE" radius="15.0" stroke="#ffffff00" strokeType="INSIDE" />
               </children>
            </StackPane>
            <StackPane minHeight="-Infinity" minWidth="-Infinity" prefHeight="44.0" prefWidth="44.0" styleClass="swatchBackground">
               <children>
                  <Circle fx:id="color3" fill="DODGERBLUE" radius="15.0" stroke="#ffffff00" strokeType="INSIDE" />
               </children>
            </StackPane>
            <StackPane minHeight="-Infinity" minWidth="-Infinity" prefHeight="44.0" prefWidth="44.0" styleClass="swatchBackground">
               <children>
                  <Circle fx:id="color4" fill="DODGERBLUE" radius="15.0" stroke="#ffffff00" strokeType="INSIDE" />
               </children>
            </StackPane>
            <StackPane minHeight="-Infinity" minWidth="-Infinity" prefHeight="44.0" prefWidth="44.0" styleClass="swatchBackground">
               <children>
                  <Circle fx:id="color5" fill="DODGERBLUE" radius="15.0" stroke="#ffffff00" strokeType="INSIDE" />
               </children>
            </StackPane>
         </children>
      </HBox>
   </children>
   <padding>
      <Insets bottom="5.0" left="5.0" right="5.0" top="5.0" />
   </padding>
</VBox>

我在我的一个项目中遇到了同样的问题，我通过在fxml文件中提供

fx:controller=

来修复它。您已经在主fxml中指定了，也可以使用

fx:controller=“SwatchCell”

//在样例fxml文件中设置控制器。无论您的类包是什么

添加您的

fxml

。如果fxml添加到原始姿势，则我无法运行您的程序。这不是MCVE。我只是看看教程。我看不到哪里

cellRootNode=fxmloader.load（）在教程中完成。本教程似乎做了
fxmloader.load（）
，仅此而已。您是如何提出您的产品线的？如前所述：请提供一个演示问题的示例；）是的，这是问题的一部分。我最终通过设置fx:controller使它工作起来，并且在单元格是否为空的情况下也出现了问题，我错过了bc。突然，我的NetBeans拒绝正确地自动格式化（缩进）我的代码。谢谢你的回答
    <?xml version="1.0" encoding="UTF-8"?>

<?import javafx.geometry.Insets?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.image.Image?>
<?import javafx.scene.image.ImageView?>
<?import javafx.scene.layout.HBox?>
<?import javafx.scene.layout.StackPane?>
<?import javafx.scene.layout.VBox?>
<?import javafx.scene.shape.Circle?>
<?import javafx.scene.text.Font?>

<VBox fx:id="cellRootNode" maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="107.0" prefWidth="255.0" spacing="5.0" style="-fx-background-color: #191919;" stylesheets="@MainWindowCSS.css" xmlns="http://javafx.com/javafx/8.0.171" xmlns:fx="http://javafx.com/fxml/1">
   <children>
      <Label fx:id="name" maxWidth="1.7976931348623157E308" text="ColorSwatch Name" textFill="WHITE" VBox.vgrow="ALWAYS" />
      <Label fx:id="tagLine" maxWidth="1.7976931348623157E308" text="TagLine" textFill="#b3b3b3">
         <graphic>
            <ImageView fitHeight="21.0" fitWidth="21.0" pickOnBounds="true" preserveRatio="true">
               <image>
                  <Image url="@../resources/tag.png" />
               </image>
            </ImageView>
         </graphic>
         <font>
            <Font size="12.0" />
         </font>
      </Label>
      <HBox prefHeight="12.0" prefWidth="64.0" spacing="5.0" VBox.vgrow="NEVER">
         <children>
            <StackPane minHeight="-Infinity" minWidth="-Infinity" prefHeight="44.0" prefWidth="44.0" styleClass="swatchBackground" HBox.hgrow="NEVER">
               <children>
                  <Circle fx:id="color1" fill="DODGERBLUE" radius="15.0" stroke="#ffffff00" strokeType="INSIDE" />
               </children>
            </StackPane>
            <StackPane minHeight="-Infinity" minWidth="-Infinity" prefHeight="44.0" prefWidth="44.0" styleClass="swatchBackground">
               <children>
                  <Circle fx:id="color2" fill="DODGERBLUE" radius="15.0" stroke="#ffffff00" strokeType="INSIDE" />
               </children>
            </StackPane>
            <StackPane minHeight="-Infinity" minWidth="-Infinity" prefHeight="44.0" prefWidth="44.0" styleClass="swatchBackground">
               <children>
                  <Circle fx:id="color3" fill="DODGERBLUE" radius="15.0" stroke="#ffffff00" strokeType="INSIDE" />
               </children>
            </StackPane>
            <StackPane minHeight="-Infinity" minWidth="-Infinity" prefHeight="44.0" prefWidth="44.0" styleClass="swatchBackground">
               <children>
                  <Circle fx:id="color4" fill="DODGERBLUE" radius="15.0" stroke="#ffffff00" strokeType="INSIDE" />
               </children>
            </StackPane>
            <StackPane minHeight="-Infinity" minWidth="-Infinity" prefHeight="44.0" prefWidth="44.0" styleClass="swatchBackground">
               <children>
                  <Circle fx:id="color5" fill="DODGERBLUE" radius="15.0" stroke="#ffffff00" strokeType="INSIDE" />
               </children>
            </StackPane>
         </children>
      </HBox>
   </children>
   <padding>
      <Insets bottom="5.0" left="5.0" right="5.0" top="5.0" />
   </padding>
</VBox>