Adding an image into a JavaFX TableView column

You have misnamed the property name used in the PropertyValueFactory.

In general, don't use PropertyValueFactories, instead use a lambda:

• Why should I avoid using PropertyValueFactory in JavaFX?

Also, as a general principle, place data in the model, not nodes. For example, instead of an ImageView, store either an Image or a URL to the image in the model. Then use nodes only in the views of the model. For example, to display an image in a table cell, use a cell factory.

An LRU cache can be used for the images if needed (it may not be needed).

Often the images displayed in a table might be smaller than the full-size image, i.e. like a thumbnail. For efficiency, you might want to load images in the background using a sizing image constructor.

If you need help placing and locating your image resources, see:

• How do I determine the correct path for FXML files, CSS files, Images, and other resources needed by my JavaFX Application?

Example code

The example in this answer uses some of the principles from the answer text:

• Uses a Lambda instead of PropertyValue.
• The model for list items is represented as a record using immutable data.
  • Replace the record with a standard class if you want read/write access to data.
• An Image URL is stored as a String in the model rather than as an ImageView node.
• A cell factory is used to provide an ImageView node to view the image.
• Images are loaded in the background and resized to thumbnail size on loading.
  • You can skip the thumbnail sizing and use full-size images if your app requires that.
  • You can load in the foreground if you want the UI to wait until the images are loaded before displaying (not recommended, but for small local images you won't see any difference).
• Images are loaded in an LRU cache.
  • If you don't have a lot of images (e.g. thousands), you could instead store the Image (not the ImageView) directly in the model and use that, removing the LRU cache from the solution.

Though I didn't test it, this solution should scale fine to a table with thousands of rows, each with different images.

The images used in this answer are provided here:

• JavaFX: ComboBox with custom cell factory - buggy rendering

ImageCell.java

import javafx.scene.control.TableCell;
import javafx.scene.image.ImageView;

public class ImageCell<S> extends TableCell<S, String> {
    private final ImageView imageView = new ImageView();
    private final ImageCache imageCache = ImageCache.getInstance();

    @Override
    protected void updateItem(String url, boolean empty) {
        super.updateItem(url, empty);

        if (url == null || empty || imageCache.getThumbnail(url) == null) {
            imageView.setImage(null);
            setGraphic(null);
        } else {
            imageView.setImage(imageCache.getThumbnail(url));
            setGraphic(imageView);
        }
    }
}

ImageCache.java

import javafx.scene.image.Image;

import java.util.Map;
import java.util.Objects;

public class ImageCache {
    private static final int IMAGE_CACHE_SIZE = 10;
    private static final int THUMBNAIL_SIZE = 64;

    private static final ImageCache instance = new ImageCache();

    public static ImageCache getInstance() {
        return instance;
    }

    private final Map<String, Image> imageCache = new LruCache<>(
            IMAGE_CACHE_SIZE
    );

    private final Map<String, Image> thumbnailCache = new LruCache<>(
            IMAGE_CACHE_SIZE
    );

    public Image get(String url) {
        if (!imageCache.containsKey(url)) {
            imageCache.put(
                    url,
                    new Image(
                            Objects.requireNonNull(
                                    ImageCache.class.getResource(
                                            url
                                    )
                            ).toExternalForm(),
                            true
                    )
            );
        }

        return imageCache.get(url);
    }

    public Image getThumbnail(String url) {
        if (!thumbnailCache.containsKey(url)) {
            thumbnailCache.put(
                    url,
                    new Image(
                            Objects.requireNonNull(
                                    ImageCache.class.getResource(
                                            url
                                    )
                            ).toExternalForm(),
                            THUMBNAIL_SIZE,
                            THUMBNAIL_SIZE,
                            true,
                            true,
                            true
                    )
            );
        }

        return thumbnailCache.get(url);
    }
}

LruCache.java

import java.util.LinkedHashMap;
import java.util.Map;

public final class LruCache<A, B> extends LinkedHashMap<A, B> {
    private final int maxEntries;

    public LruCache(final int maxEntries) {
        super(maxEntries + 1, 1.0f, true);
        this.maxEntries = maxEntries;
    }

    @Override
    protected boolean removeEldestEntry(final Map.Entry<A, B> eldest) {
        return super.size() > maxEntries;
    }
}

Student.java

public record Student(
        String last,
        String first,
        String avatar
) {}

StudentTableApp.java

import javafx.application.Application;
import javafx.beans.property.ReadOnlyStringWrapper;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class StudentTableApp extends Application {
    @Override
    public void start(Stage stage) {
        TableView<Student> table = createTable();
        populateTable(table);

        VBox layout = new VBox(
                10,
                table
        );
        layout.setPadding(new Insets(10));
        layout.setPrefSize(340, 360);

        layout.setStyle("-fx-font-size:20px; -fx-base: antiquewhite");

        stage.setScene(new Scene(layout));
        stage.show();
    }

    private TableView<Student> createTable() {
        TableView<Student> table = new TableView<>();

        TableColumn<Student, String> lastColumn = new TableColumn<>("Last");
        lastColumn.setCellValueFactory(
                p -> new ReadOnlyStringWrapper(
                        p.getValue().last()
                ).getReadOnlyProperty()
        );

        TableColumn<Student, String> firstColumn = new TableColumn<>("First");
        firstColumn.setCellValueFactory(
                p -> new ReadOnlyStringWrapper(
                        p.getValue().first()
                ).getReadOnlyProperty()
        );

        TableColumn<Student, String> avatarColumn = new TableColumn<>("Avatar");
        avatarColumn.setCellValueFactory(
                p -> new ReadOnlyStringWrapper(
                        p.getValue().avatar()
                ).getReadOnlyProperty()
        );
        avatarColumn.setCellFactory(
                p -> new ImageCell<>()
        );
        avatarColumn.setPrefWidth(70);

        table.getColumns().addAll(
                List.of(
                        lastColumn, firstColumn, avatarColumn
                )
        );

        return table;
    }

    private void populateTable(TableView<Student> table) {
        table.getItems().addAll(
                new Student("Dragon", "Smaug", "Dragon-icon.png"),
                new Student("Snake-eyes", "Shifty", "Medusa-icon.png"),
                new Student("Wood", "Solid", "Treant-icon.png"),
                new Student("Rainbow", "Magical", "Unicorn-icon.png")
        );
    }
}