7 Managing Web Pop-Up Windows
This chapter explains how to work with pop-up windows in the browser created by using the WebView
component and how to implement this functionality in the WebViewSample application.
When you need to open a new browser window in your application, the instances of the PopupFeatures
class are passed into pop-up handlers registered on a WebEngine
object by using the setCreatePopupHandler
method.
Using Pop-Up Windows to Set
In the WebViewSample application, you can set an alternative WebView
object for the documents that will be opened in a separate window. Figure 7-1 shows a context menu a user can open by right-clicking any link.
To specify a new browser window for the target document, use the PopupFeatures
instance as shown in the modified application code in Example 7-1.
Example 7-1 Processing a Command of a Pop-Up Window
import javafx.application.Application; import javafx.application.Platform; import javafx.beans.value.ObservableValue; import javafx.concurrent.Worker.State; import javafx.event.ActionEvent; import javafx.geometry.HPos; import javafx.geometry.Pos; import javafx.geometry.VPos; import javafx.scene.Node; import javafx.scene.Scene; import javafx.scene.control.Button; import javafx.scene.control.Hyperlink; import javafx.scene.image.Image; import javafx.scene.image.ImageView; import javafx.scene.layout.HBox; import javafx.scene.layout.Priority; import javafx.scene.layout.Region; import javafx.scene.paint.Color; import javafx.scene.web.PopupFeatures; import javafx.scene.web.WebEngine; import javafx.scene.web.WebView; import javafx.stage.Stage; import netscape.javascript.JSObject; public class WebViewSample extends Application { private Scene scene; @Override public void start(Stage stage) { // create scene stage.setTitle("Web View Sample"); scene = new Scene(new Browser(stage), 900, 600, Color.web("#666970")); stage.setScene(scene); // apply CSS style scene.getStylesheets().add("webviewsample/BrowserToolbar.css"); // show stage stage.show(); } public static void main(String[] args) { launch(args); } } class Browser extends Region { private final HBox toolBar; final private static String[] imageFiles = new String[]{ "product.png", "blog.png", "documentation.png", "partners.png", "help.png" }; final private static String[] captions = new String[]{ "Products", "Blogs", "Documentation", "Partners", "Help" }; final private static String[] urls = new String[]{ "http://www.oracle.com/products/index.html", "http://blogs.oracle.com/", "http://docs.oracle.com/javase/index.html", "http://www.oracle.com/partners/index.html", WebViewSample.class.getResource("help.html").toExternalForm() }; final ImageView selectedImage = new ImageView(); final Hyperlink[] hpls = new Hyperlink[captions.length]; final Image[] images = new Image[imageFiles.length]; final WebView browser = new WebView(); final WebEngine webEngine = browser.getEngine(); final Button toggleHelpTopics = new Button("Toggle Help Topics"); private boolean needDocumentationButton = false; final WebView smallView = new WebView(); public Browser(final Stage stage) { //apply the styles getStyleClass().add("browser"); for (int i = 0; i < captions.length; i++) { // create hyperlinks Hyperlink hpl = hpls[i] = new Hyperlink(captions[i]); Image image = images[i] = new Image(getClass().getResourceAsStream(imageFiles[i])); hpl.setGraphic(new ImageView(image)); final String url = urls[i]; final boolean addButton = (hpl.getText().equals("Help")); // process event hpl.setOnAction((ActionEvent e) -> { needDocumentationButton = addButton; webEngine.load(url); }); } // create the toolbar toolBar = new HBox(); toolBar.setAlignment(Pos.CENTER); toolBar.getStyleClass().add("browser-toolbar"); toolBar.getChildren().addAll(hpls); toolBar.getChildren().add(createSpacer()); //set action for the button toggleHelpTopics.setOnAction((ActionEvent t) -> { webEngine.executeScript("toggle_visibility('help_topics')"); }); smallView.setPrefSize(120, 80); //handle popup windows webEngine.setCreatePopupHandler( (PopupFeatures config) -> { smallView.setFontScale(0.8); if (!toolBar.getChildren().contains(smallView)) { toolBar.getChildren().add(smallView); } return smallView.getEngine(); }); // process page loading webEngine.getLoadWorker().stateProperty().addListener( (ObservableValue<? extends State> ov, State oldState, State newState) -> { toolBar.getChildren().remove(toggleHelpTopics); if (newState == State.SUCCEEDED) { JSObject win = (JSObject) webEngine.executeScript("window"); win.setMember("app", new JavaApp()); if (needDocumentationButton) { toolBar.getChildren().add(toggleHelpTopics); } } }); // load the home page webEngine.load("http://www.oracle.com/products/index.html"); //add components getChildren().add(toolBar); getChildren().add(browser); } // JavaScript interface object public class JavaApp { public void exit() { Platform.exit(); } } private Node createSpacer() { Region spacer = new Region(); HBox.setHgrow(spacer, Priority.ALWAYS); return spacer; } @Override protected void layoutChildren() { double w = getWidth(); double h = getHeight(); double tbHeight = toolBar.prefHeight(w); layoutInArea(browser,0,0,w,h-tbHeight,0,HPos.CENTER,VPos.CENTER); layoutInArea(toolBar,0,h-tbHeight,w,tbHeight,0,HPos.CENTER,VPos.CENTER); } @Override protected double computePrefWidth(double height) { return 900; } @Override protected double computePrefHeight(double width) { return 600; } }
When a user selects the Open Link in New Window option from the pop-up menu, the smallView
browser is added to the application toolbar. This behavior is defined by the setCreatePopupHandler
method, which returns the web engine of an alternative browser to notify the application where to render the target page. The result of compiling and running the modified application is shown in Figure 7-2.
Note that context menus are enabled by default for all WebView
objects. To disable a context menu for a particular WebView
instance, pass the false value to the setContextMenuEnabled
method: browser.setContextMenuEnabled(false);
.