javafX8初探（超链接）

本章我们来介绍，如何把文本转化成超链接。

Hyperlink类代表了另一种形式的Label。下图描述了3中状态的超链接：

创建超链接

 

下面的代码块创建了一个超链接

Hyperlink link = new Hyperlink();
link.setText("http://example.com");
link.setOnAction((ActionEvent e) -> {
    System.out.println("This link is clicked");
});

 

实例方法setText定义了超链接的文本内容。因为Hyperlink类是Labeled类的扩展，所以我们可以指定内容和字体。setOnAction方法设置了一个特定的事件，当超链接被点击的时候这个事件就触发了，这和Button是一样的。上面的例子当点击的时候打印一行字符串，当然在你的例子中你可能会做更复杂的操作。

连接本地内容

源码如下：

import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.scene.*;
import javafx.scene.control.*;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class HyperlinkSample extends Application {

    final static String[] imageFiles = new String[]{
        "product.png",
        "education.png",
        "partners.png",
        "support.png"
    };
    final static String[] captions = new String[]{
        "Products",
        "Education",
        "Partners",
        "Support"
    };
    final ImageView selectedImage = new ImageView();
    final ScrollPane list = new ScrollPane();
    final Hyperlink[] hpls = new Hyperlink[captions.length];
    final Image[] images = new Image[imageFiles.length];

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

    @Override
    public void start(Stage stage) {
        Scene scene = new Scene(new Group());
        stage.setTitle("Hyperlink Sample");
        stage.setWidth(300);
        stage.setHeight(200);

        selectedImage.setLayoutX(100);
        selectedImage.setLayoutY(10);

        for (int i = 0; i < captions.length; i++) {
            final Hyperlink hpl = hpls[i] = new Hyperlink(captions[i]);
            final Image image = images[i] = new Image(
                getClass().getResourceAsStream(imageFiles[i])
            );
            hpl.setOnAction((ActionEvent e) -> {
                selectedImage.setImage(image);
            });
        }

        final Button button = new Button("Refresh links");
        button.setOnAction((ActionEvent e) -> {
            for (int i = 0; i < captions.length; i++) {
                hpls[i].setVisited(false);
                selectedImage.setImage(null);
            }
        });

        VBox vbox = new VBox();
        vbox.getChildren().addAll(hpls);
        vbox.getChildren().add(button);
        vbox.setSpacing(5);

        ((Group) scene.getRoot()).getChildren().addAll(vbox, selectedImage);
        stage.setScene(scene);
        stage.show();
    }
}

 

连接远程内容

如果我们在应用中使用WebView浏览器，我们就可以加载HTML的内容。WebView提供了基本的网页浏览能力。它可以加载web网页并且支持交互，比如：导航链接和执行javaScript命令。

import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.geometry.Pos;
import javafx.scene.*;
import javafx.scene.control.*;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.layout.HBox;
import javafx.scene.layout.Priority;
import javafx.scene.layout.VBox;
import javafx.scene.text.Font;
import javafx.scene.web.WebEngine;
import javafx.scene.web.WebView;
import javafx.stage.Stage;

public class HyperlinkWebViewSample extends Application {

    final static String[] imageFiles = new String[]{
        "product.png",
        "education.png",
        "partners.png",
        "support.png"
    };
    final static String[] captions = new String[]{
        "Products",
        "Education",
        "Partners",
        "Support"
    };

    final static String[] urls = new String[]{
        "http://www.oracle.com/us/products/index.html",
        "http://education.oracle.com/",
        "http://www.oracle.com/partners/index.html",
        "http://www.oracle.com/us/support/index.html"
    };

    final ImageView selectedImage = new ImageView();
    final Hyperlink[] hpls = new Hyperlink[captions.length];
    final Image[] images = new Image[imageFiles.length];   

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

    @Override
    public void start(Stage stage) {
        VBox vbox = new VBox();
        Scene scene = new Scene(vbox);
        stage.setTitle("Hyperlink Sample");
        stage.setWidth(570);
        stage.setHeight(550);

        selectedImage.setLayoutX(100);
        selectedImage.setLayoutY(10);

        final WebView browser = new WebView();
        final WebEngine webEngine = browser.getEngine();

        for (int i = 0; i < captions.length; i++) {
            final Hyperlink hpl = hpls[i] = new Hyperlink(captions[i]);
            final Image image = images[i] =
                new Image(getClass().getResourceAsStream(imageFiles[i]));
            hpl.setGraphic(new ImageView (image));
            hpl.setFont(Font.font("Arial", 14));
            final String url = urls[i];

            hpl.setOnAction((ActionEvent e) -> {
                webEngine.load(url);
            });
        }

        HBox hbox = new HBox();
        hbox.setAlignment(Pos.BASELINE_CENTER);
        hbox.getChildren().addAll(hpls);
        vbox.getChildren().addAll(hbox, browser);
        VBox.setVgrow(browser, Priority.ALWAYS);

        stage.setScene(scene);
        stage.show();
    }
}

运行如下图所示：