Customize ListView in JavaFX with FXML

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無奈伤痛
無奈伤痛 2020-11-29 22:05

I want to make a customize list view in javafx. Here I need to bind multiple component in list cell as follow, like one label, one textfield, one button under one HBox and

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  • 2020-11-29 22:12

    The answer by Anvay for some reason didnt work for me, what i had to do to fix it was just some very small tweaks:

    1. remove import data statement from listCellItem.fxml
    2. as the comment below the post states in Data.java put hBox = fmxlLoader.load()
    3. I also had a main class (intellij auto generated).

      public class MainMain extends Application {
      
      @Override
      public void start(Stage primaryStage) throws Exception{
      
      FXMLLoader fxmlLoader = new 
      FXMLLoader(getClass().getResource("MainController.fxml"));
      try
      {
          Parent root = fxmlLoader.load();
      
          Scene scene = new Scene(root);
          primaryStage.setScene(scene);
          primaryStage.setTitle("Title");
          primaryStage.show();
      }
      catch (IOException e)
      {
          throw new RuntimeException(e);
      }
      }
      
      
      
      public static void main(String[] args) {
          launch(args);
      }
      

    I know this was probably obvious for most of the experts here, but these issues perplexed me for hours while i was debugging.

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  • 2020-11-29 22:14

    I understand your question. There are mainly two ways to set items in a Listview:

    1. Create the ObservableList and set the items of the ListView with the ObservableList (listView.setItems(observableList)).

    2. Use the setCellFactory() method of the ListView class.

    You would prefer to use the setCellFactory() method, because this approach simplies the process as well as it helps to separate out the business logic and the UI (FXML).


    Here is a more detailed explaination:


    1. Create a new FXML file with the name listview.fxml to contain the ListView, and set the ListViewController class as its controller:

    File: listview.fxml:

    <?import javafx.scene.layout.GridPane?>
    <?import javafx.scene.control.ListView?>
    <?import demo.ListViewController?>
    
    <GridPane xmlns:fx="http://javafx.com/fxml" alignment="CENTER">
         <ListView fx:id="listView"/>
    </GridPane>
    

    2. Create the controller and name it ListViewController.
    The controller can load the listview.fxml file and access the listview.

    File: ListViewController.java:

    package demo;
    
    import javafx.collections.FXCollections;
    import javafx.collections.ObservableList;
    import javafx.fxml.FXML;
    import javafx.fxml.FXMLLoader;
    import javafx.scene.*;
    import javafx.scene.control.*;
    import javafx.util.Callback;
    import java.io.IOException;
    import java.util.Set;
    
    public class ListViewController
    {
        @FXML
        private ListView listView;
        private Set<String> stringSet;
        ObservableList observableList = FXCollections.observableArrayList();
    
        public ListViewController()
        {
            FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("/fxml/listview.fxml"));
            fxmlLoader.setController(this);
            try
            {
                Parent parent = (Parent)fxmlLoader.load();
                Scene scene = new Scene(parent, 400.0 ,500.0);
            }
            catch (IOException e)
            {
                throw new RuntimeException(e);
            }
        }
    
        public void setListView()
        {
            stringSet.add("String 1");
            stringSet.add("String 2");
            stringSet.add("String 3");
            stringSet.add("String 4");
            observableList.setAll(stringSet);
            listView.setItems(observableList);
            listView.setCellFactory(new Callback<ListView<String>, javafx.scene.control.ListCell<String>>()
            {
                @Override
                public ListCell<String> call(ListView<String> listView)
                {
                    return new ListViewCell();
                }
            });
        }
    }
    

    3. First you need to set the value of the ObservableList. This is very important.
    Then, set the items of list using the ObservableList and call the setCellFactory() method on the ListView. In the given example I just take the String values an add them to the String set (the Set<String> stringSet).


    4. When the setCellFactory() method is called on the ListView, it will return the ListCell. So for sake of simplicity, I added a class which extends the ListCell, and the setGraphic() method is present for the ListCell() and will set the items of the ListCell.

    File: ListViewCell.java:

    package demo;
    
    import javafx.scene.control.ListCell;
    
    public class ListViewCell extends ListCell<String>
    {
        @Override
        public void updateItem(String string, boolean empty)
        {
            super.updateItem(string,empty);
            if(string != null)
            {
                Data data = new Data();
                data.setInfo(string);
                setGraphic(data.getBox());
            }
        }
    }
    

    5. I just added a class which will load the listCellItem.fxml and return the HBox, which will contain the other components as children.
    The HBox is then set to the ListCell.

    File: listCellItem.fxml:

     <?import demo.Data?>
     <?import javafx.scene.layout.HBox?>
     <?import javafx.scene.control.Label?>
    
    <HBox xmlns:fx="http://javafx.com/fxml" fx:id="hBox">
    <children>
        <Label  fx:id="label1"/>
        <Label  fx:id="label2"/>
    </children>
    </HBox>
    

    File: Data.java:

    package demo;
    
    import javafx.fxml.FXML;
    import javafx.fxml.FXMLLoader;
    import javafx.scene.control.Label;
    import javafx.scene.layout.HBox;
    import java.io.IOException;
    
    public class Data
    {
        @FXML
        private HBox hBox;
        @FXML
        private Label label1;
        @FXML
        private Label label2;
    
        public Data()
        {
            FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("/fxml/listCellItem.fxml"));
            fxmlLoader.setController(this);
            try
            {
                fxmlLoader.load();
            }
            catch (IOException e)
            {
                throw new RuntimeException(e);
            }
        }
    
        public void setInfo(String string)
        {
            label1.setText(string);
            label2.setText(string);
        }
    
        public HBox getBox()
        {
            return hBox;
        }
    }
    

    Using this way, you can use the setCellFactory() method to separate the things that are business logic and FXML.

    Hope this is helpful.

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  • 2020-11-29 22:26

    The example above by @Anvay needs a couple of tweaks to work. These are simple things to set on-track.

    1. The ListViewController needs to be running on the JavaFX application thread.
    2. You can only call the injected @FXML elements from the JavaFX initialize() method
    3. Need to call setListView()
    4. The stringSet in the example needs to be allocated with a new before calling setListView().

    The ListViewController below works with these changes. I changed "stringSet" to a list, "stringList". The controller is pretty much the sample controller provided by Scene Builder 2

     public class ListViewController 
     {
    
         @FXML private   ResourceBundle      resources;
    
         @FXML private   URL                 location;
    
         @FXML private   ListView            listView;
    
         private         List<String>        stringList     = new ArrayList<>(5);
         private         ObservableList      observableList = FXCollections.observableArrayList();
    
         public void setListView(){
    
             stringList.add("String 1");
             stringList.add("String 2");
             stringList.add("String 3");
             stringList.add("String 4");
    
             observableList.setAll(stringList);
    
             listView.setItems(observableList);
    
             listView.setCellFactory(
                 new Callback<ListView<String>, javafx.scene.control.ListCell<String>>() {
                     @Override
                     public ListCell<String> call(ListView<String> listView) {
                         return new ListViewCell();
                     }
                 });
         }
    
         @FXML
         void initialize() {
             assert listView != null : "fx:id=\"listView\" was not injected: check your FXML file 'CustomList.fxml'.";
    
             setListView();
         }
    
     }//ListViewController
    

    The JavaFX platform needs to be started in the main() method from a JavaFX Application. Netbeans conviently provides most of this structure from the Maven JavaFX application template.

    public class MainApp extends Application {
    
        @Override
        public void start(Stage stage) throws Exception {
    
            Parent root = FXMLLoader.load(getClass().getResource("/fxml/CustomList.fxml"));
    
            Scene scene = new Scene(root);
            scene.getStylesheets().add("/styles/Styles.css");
    
            stage.setTitle("CustomList");
            stage.setScene(scene);
            stage.show();
        }
    
        /**
         *  The main() method is ignored in correctly deployed JavaFX application.
         * 
         *  @param args the command line arguments
         **/
        public static void main(String[] args) {
    
            launch(args);
        }
    }
    
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