JavaFx:如何将ImageView放在ListView中

Question

我一直在搜索关于JavaFx ListView的一些线程,但仍然很难找到一个简单而简单的解决方案,用于将JavaFx ImageView放入JavaFx ListView中.我正在尝试使用JavaFx框架创建一个聊天应用程序.它应该看起来像那样.这不是重复的,因为另一个线程对于像我这样的初学者来说是模糊的.带有imageview的ListView

我试过这样的事.我提前感谢你们!

import javafx.application.Application;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.Scene;
import javafx.scene.control.ListCell;
import javafx.scene.control.ListView;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.layout.Priority;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class Main extends Application {
     ImageView imageView = new ImageView();
     Image image = new Image(Main.class.getResourceAsStream("bell.jpg"));
    ListView<String> list = new ListView<String>();
    ObservableList<String> data = FXCollections.observableArrayList(
            "chocolate", "salmon", "gold", "coral", "darkorchid",
            "darkgoldenrod", "lightsalmon", "black", "rosybrown", "blue",
            "blueviolet", "brown");
   Image pic;

    @Override
    public void start(Stage stage) {
        VBox box = new VBox();
        Scene scene = new Scene(box, 200, 200);
        stage.setScene(scene);
        stage.setTitle("ListViewSample");
        box.getChildren().addAll(list);
        VBox.setVgrow(list, Priority.ALWAYS);
        list.setItems(data);

        list.setCellFactory(listView -> new ListCell<String>() {
            public void updateItem(String friend, boolean empty) {
                super.updateItem(friend, empty);
                if (empty) {
                    setText(null);
                    setGraphic(null);
                } else {

                    imageView.setImage(image);
                    setText(friend);
                    setGraphic(imageView);
                }
            }

        });

        stage.show();
    }


    public static void main(String[] args) {
        launch(args);
    }
}`

Answer 1

每次要在ListView中设置图像时,都不需要创建新的HBox.您可以直接使用setCellFactory()ListView来实现相同的结果.

此示例只是JavaFX ListView中答案Image的扩展,包含一个可以尝试和测试的Minimal,Complete和Verifiable示例.如果你想了解它是如何工作的,我建议你首先查看链接的问题.

更新 - 如何调整图像大小

要调整图像大小以适合您想要的大小,请使用ImageView的fitWidth()和fitHeight()方法.还有其他方法,如setSmooth()和setPreserveRatio(),它们也可以派上用场.

MCVE

import javafx.application.Application;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.ListCell;
import javafx.scene.control.ListView;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class ListViewWithImages extends Application {

    private final Image IMAGE_RUBY  = new Image("https://upload.wikimedia.org/wikipedia/commons/f/f1/Ruby_logo_64x64.png");
    private final Image IMAGE_APPLE  = new Image("http://findicons.com/files/icons/832/social_and_web/64/apple.png");
    private final Image IMAGE_VISTA  = new Image("http://antaki.ca/bloom/img/windows_64x64.png");
    private final Image IMAGE_TWITTER = new Image("http://files.softicons.com/download/social-media-icons/fresh-social-media-icons-by-creative-nerds/png/64x64/twitter-bird.png");

    private Image[] listOfImages = {IMAGE_RUBY, IMAGE_APPLE, IMAGE_VISTA, IMAGE_TWITTER};

    @Override
    public void start(Stage primaryStage) throws Exception {

        ListView<String> listView = new ListView<String>();
        ObservableList<String> items =FXCollections.observableArrayList (
                "RUBY", "APPLE", "VISTA", "TWITTER");
        listView.setItems(items);

        listView.setCellFactory(param -> new ListCell<String>() {
            private ImageView imageView = new ImageView();
            @Override
            public void updateItem(String name, boolean empty) {
                super.updateItem(name, empty);
                if (empty) {
                    setText(null);
                    setGraphic(null);
                } else {
                    if(name.equals("RUBY"))
                        imageView.setImage(listOfImages[0]);
                    else if(name.equals("APPLE"))
                        imageView.setImage(listOfImages[1]);
                    else if(name.equals("VISTA"))
                        imageView.setImage(listOfImages[2]);
                    else if(name.equals("TWITTER"))
                        imageView.setImage(listOfImages[3]);
                    setText(name);
                    setGraphic(imageView);
                }
            }
        });
        VBox box = new VBox(listView);
        box.setAlignment(Pos.CENTER);
        Scene scene = new Scene(box, 200, 200);
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }
}

OUTPUT