How do I load live DOM in Java Application? - java

I'm not really sure how to ask this question but here is what I am trying to do. I am looking for the ability to load a website in java application and being able to click the buttons, text, box, etc and get the underlying DOM code.
For example:
-It loads google.com the webpage as well as the LIVE DOM under it, different frame. It can't be HTML since google is javascript.
-I want to click the google search box, or anything on the page, and application will print any attribute, such as name="q" or just q.
I've looked into XULrunner but it is deprecated for java.

You can use JavascriptExecutor for that. It is implemented by all WebDrivers. See JavaDoc for details. Use documentto refer to the DOM.

You can use JavaFX WebView.
You can call back to your Java code from Javascript. So you could write a small amount of Javascript that detects when the user clicked on element, and call some Java code that shows attribute value, for example. See "Calling back to Java from Javascript" in the WebEngine API docs.
Sample code:
public class HTMLMouseOverTest extends Application {
#Override
public void start(Stage primaryStage) {
final BorderPane root = new BorderPane();
final WebView webView = new WebView();
final WebEngine engine = webView.getEngine();
final BooleanProperty mouseOver = new SimpleBooleanProperty();
engine.getLoadWorker().stateProperty().addListener(new ChangeListener<State>() {
#Override
public void changed(ObservableValue<? extends State> observable,
State oldValue, State newValue) {
if (newValue == State.SUCCEEDED) {
// Here's how to add the Javascript if you don't have
// direct access to the HTML:
// final Document doc = engine.getDocument();
// Element div = doc.getElementById("important-div");
// div.setAttribute("onmouseover", "mouseOverProperty.set(true)");
// div.setAttribute("onmouseout", "mouseOverProperty.set(false)");
final JSObject window = (JSObject) engine.executeScript("window");
window.setMember("mouseOverProperty", mouseOver);
}
}
});
engine.loadContent("<html><body style='font-family:sans-serif';><h2>Hello World</h2>"+
"<div id='important-div' onmouseover='mouseOverProperty.set(true)'"+
"onmouseout='mouseOverProperty.set(false)' style='background: #ffd; padding:40px;'>"+
"Move mouse here</div>"+
"<h3>Thanks and good night</h3></body></html>");
root.setCenter(webView);
final Label label = new Label();
label.textProperty().bind(Bindings.when(mouseOver).then("Mouse in position").otherwise("Mouse out of area"));
root.setBottom(label);
final Scene scene = new Scene(root, 400, 250);
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}

Related

Graph not rendering in JavaFX on startup under Java 11

The issue I'm having is that the mxGraph object does not load correctly on startup. It requires me to click a cell inside of it for it to appear, and even then it does not reveal the entire graph, just the cell that was clicked. In order to reveal all of it I have to refresh the graph via another control or drag a cell around the entire graph area.
When I initially developed this I was working with Java 8 and this was not an issue. This has only occurred since updating to Java 11 (OpenJDK). Everything else was kept the same when upgrading to 11, only the updated dependencies changed.
I am wrapping the mxGraphComponent inside of a SwingNode in order to place it inside of a JavaFX node. I've had issues in the past with Swing nodes inside JavaFX but I am creating all of the Swing components using the SwingUtilities.invokeLater() method. I am using the 3.9.8.1 version of JGraphX from Maven, but I have also tried the updated 4.0.0 from GitHub with no success.
Here's my MCVE:
public final class Main {
public static void main(final String[] args) {
Application.launch(JGraphExample.class);
}
}
public final class JGraphExample extends Application {
private mxGraph graph;
#Override
public void start(final Stage primaryStage) {
final SwingNode value = new SwingNode();
final BorderPane root = new BorderPane();
root.setCenter(value);
root.setBottom(createRefreshButton());
SwingUtilities.invokeLater(() -> value.setContent(buildGraphComponent()));
primaryStage.setWidth(500);
primaryStage.setHeight(500);
primaryStage.setScene(new Scene(root));
primaryStage.show();
}
private mxGraphComponent buildGraphComponent() {
graph = buildGraph();
return new mxGraphComponent(graph);
}
private mxGraph buildGraph() {
final mxGraph graph = new mxGraph();
graph.insertVertex(graph.getDefaultParent(), "x", "Hello", 100, 100, 100, 100);
return graph;
}
private Button createRefreshButton() {
final Button refresh = new Button("Refresh");
refresh.setOnAction(actionEvent -> graph.refresh());
return refresh;
}
}
Until clicking the refresh button the graph will not render correctly. This was not the case with Java 8 as it worked as intended. It seems the update to 11 has teased this issue out.
Has anyone come across this before or have any ideas? Thanks in advance.

JSException in Javafx webview

I'm getting some weird behaviour that I don't understand. I have a class MonologueTab:
public final class MonologueTab extends VBox{
private MonologueNode node;
WebView webView;
WebEngine webEngine;
public MonologueTab(){
this.node = Game.getInstance().getMonologueDatabase().getMonologueNode();
webView = new WebView();
webEngine = webView.getEngine();
createGui();
}
public void createGui(){
Label textLabel = new Label ();
textLabel.setGraphic(webView);
textLabel.setContentDisplay(ContentDisplay.GRAPHIC_ONLY);
webEngine.loadContent(node.getNextLine());
this.getChildren().add(textLabel);
textLabel.setOnMouseClicked((MouseEvent event) -> {
String nextLine = node.getNextLine();
if (nextLine!=null){
webEngine.executeScript("document.getElementById('content').insertAdjacentHTML( 'beforeend'," + nextLine + ");");
webEngine.executeScript("window.scrollTo(0, document.body.scrollHeight);");
}
else{
EventManager.getInstance().notifyObserver("end" + node.getStartTrigger());
}
});
}
}
that works as expected. But when I try to port basically the same code in to a new class DialogueTab:
public final class DialogueTab extends VBox implements EventObserver{
WebView webView;
WebEngine webEngine;
public DialogueTab(){
webView = new WebView();
webEngine = webView.getEngine();
EventManager.getInstance().addObserver(this);
createGui();
}
public void createGui(){
this.getChildren().removeAll(this.getChildren());
Label conversation = new Label();
conversation.setGraphic(webView);
conversation.setContentDisplay(ContentDisplay.GRAPHIC_ONLY);
webEngine.loadContent("<body><b>Available Conversations</b><br><div id='content'></div></body>");
this.getChildren().add(conversation);
for (Person p: Game.getInstance().getPeopleAt()){
webEngine.executeScript("document.getElementById('content').insertAdjacentHTML('beforeend', " + p.getShortDesc() + ");");
//some irrelevance removed
}
}
It's throwing a:
netscape.javascript.JSException: TypeError: null is not an object (evaluating 'document.getElementById('content').insertAdjacentHTML')
Now, I'm assuming that this is related to the issue here but I don't understand why it's working fine in one place but not in another.
I think why the first example works is because the scripts are only executed upon mouseclick (by which time the page should be fully loaded); While the second example execute the scripts direcly after it has requested to start loading (which is so fast after starting that it can't possibly be finnished loading).
As for the solution, you provided the answer yourself in the post you linked. If you need any further explanation, feel free to ask.

JavaFX Webview : load succeeds but render fails

I have a Webview (JavaFX 8) that load an article from Wikipedia.
I put a refresh button to allow a refresh, basically, it does another call to the load method of the webEngine of the WebView with the same URL. But about 50% of the time the article is never rendered. In this case, I can right-click on the web view to manually refresh, then it will be rendered successfully.
I tried to look at the LoadWorker state, it always says "SUCCEED"...
Below is a short runnable Test class that demonstrates my point.
public class Test1 extends Application {
#Override
public void start(Stage primaryStage) throws Exception {
final WebView webView = new WebView();
webView.getEngine()
.load("http://fr.wikipedia.org/wiki/Sp%C3%A9cial:Page_au_hasard");
Tab tab = new Tab("webView", webView);
TabPane tabPane = new TabPane(tab);
BorderPane borderPane = new BorderPane(tabPane);
Button buttonRefresh = new Button("Refresh");
buttonRefresh.setOnAction(new EventHandler<ActionEvent>() {
public void handle(ActionEvent event) {
webView.getEngine()
.load("http://fr.wikipedia.org/wiki/Sp%C3%A9cial:Page_au_hasard");
}
});
borderPane.setBottom(buttonRefresh);
Scene scene = new Scene(borderPane);
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main (String[] args) {
launch(args);
}
}
Am I doing something wrong? Does anyone know where this problem might come from?
EDIT
I added a few lines to bypass the problem, I check the header in the DOM when the state of the loadWorker becomes SUCCESS. If it is empty, I reload. Now it (looks) 100% ok, but still I am very curious why it didn't simply work all the time first.
Some thoughts that may be useful
The link http://fr.wikipedia.org/wiki/Sp%C3%A9cial:Page_au_hasard redirects to a random article (that's why my refresh button can't use webView.getEngine.reload()).
Putting a ChangeListener on the stateProperty of the workLoader to call the reload method of webEngine actually works. Each page is rendered successfully, but already rendered page will also be re-rendered, which is terrible.

javafx combobox dropdown go out from the edges of the screen

I have the last version of java(8_40) and javaFX.
I have a checkbox with 10 items.
I compile and run the program.
If i move the program window to the bottom of the monitor screen, the dropdown list go out from the monitor screen. It is impossible to click the items out the screen.
Instead, if I try to do the same layout with scenes builder 2.0, click on preview, the dropdown is moved automatically up for not exit the screen.
Why with scenes builder is properly displayed, instead with "compile and run" not?
The problem is the same that if I do graphics via code is that if I use the files fxml.
I put below a small program example that gives me this error:
Component CustomControl.java
public class CustomControl extends VBox {
public CustomControl() {
ComboBox<String> asd = new ComboBox<String>();
ObservableList<String> data = FXCollections.observableArrayList();
asd.setItems(data);
data.add("1");
data.add("2");
data.add("3");
data.add("4");
data.add("5");
data.add("6");
data.add("7");
data.add("8");
data.add("9");
data.add("10");
getChildren().add(asd);
}
}
Main.java
public class CustomControlExample extends Application {
public static void main(String[] args) {
launch(args);
}
String address = " ";
#Override public void start(Stage stage) {
stage.setTitle("ComboBoxSample");
Scene scene = new Scene(new CustomControl());
stage.setScene(scene);
stage.show();
}
}
EDIT:
Screen-shot on the left the pop-up go out of the screen border (eclipse)
While, on the right the pop-up is automatically moved (Scene builder)
See this image:
It is easy to solve, just change the visible row count.

javafx snapshot without showing application or Scene

Hi i'm using JavaFx WebView to create Screenshot of HTML pages and it works fine but i wanted to know is it possible to do this without launching the application in Graphical Windows!! I mean aren't there any more lightweight method to get the screenshot then this:
public class WebViewSample extends Application {
private Scene scene;
#Override
public void start(Stage stage) {
// create scene
scene = new Scene(new Browser(snapshot), 750, 500, Color.web("#666970"));
stage.setScene(scene);
// show stage
stage.show();
}
WritableImage snapshot;
public static void main(String[] args) {
launch(args);
System.err.println("launched!");
}
}
class Browser extends Region {
final ImageView selectedImage = new ImageView();
final WebView browser = new WebView();
final WebEngine webEngine = browser.getEngine();
private final WritableImage snapshotImage;
public Browser(WritableImage snapshot) {
this.snapshotImage= snapshot;
// process page loading
webEngine.getLoadWorker().stateProperty().addListener(
new ChangeListener<State>() {
#Override
public void changed(ObservableValue<? extends State> ov,
State oldState, State newState) {
if (newState == State.SUCCEEDED) {
WritableImage newSnapshot = browser.snapshot(null, snapshotImage);
File file = new File("test2.png");
RenderedImage renderedImage = SwingFXUtils.fromFXImage(newSnapshot, null);
try {
ImageIO.write(renderedImage, "png", file);
} catch (IOException e1) {
e1.printStackTrace();
}
System.exit(0);
}
}
}
);
// load the home page
webEngine.load("http://localhost/");
//add components
getChildren().add(browser);
}
}
For JavaFX 2.2 and below, there's not functionality of the kind.
Headless JavaFX applications are currently not possible, and a main JavaFX thread is mandatory.
The best you can do is read upon several workarounds for achieving this.
Related StackOverflow questions:
JavaFX for server-side image generation
Generating image at server side using Java FX
JavaFx in headless mode
How to test JavaFX 2 in a headless environment?

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