Menu
I tried to create a simple example of callback from Javascript to Java, based on the last example in WebEngine's javadoc (Calling back to Java from JavaScript). But when I click the link in the WebView, the Java method is not called and the page disappears.
public class TestOnClick extends Application {
@Override
public void start(Stage stage) throws Exception {
try {
final WebView webView = new WebView();
final WebEngine webEngine = webView.getEngine();
Scene scene = new Scene(webView);
stage.setScene(scene);
stage.setWidth(1200);
stage.setHeight(600);
stage.show();
String webPage = "<html>\n"
+ " <body>\n"
+ " <a href=\"\" onclick=\"app.onClick()\">Click here</a>\n"
+ " </body>\n"
+ "</html>";
System.out.println(webPage);
webView.getEngine().loadContent(webPage);
JSObject window = (JSObject) webEngine.executeScript("window");
window.setMember("app", new JavaApp());
} catch (Exception e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
launch(args);
}
public static class JavaApp {
public void onClick() {
System.out.println("Clicked");
}
}
}
Note: I don't see any exceptions being thrown in the WebView when monitoring the load worker with webView.getEngine().getLoadWorker().exceptionProperty().addListener(...).
916
WebView allows you to bind JavaScript code to Android code through an interface. To do this, we must use the addJavaScriptInterface() method, which is passed the class that provides the interface for JS, and the name that will be used to display the instance in JS (for example, “AndroidFunction“).
JavaScript is disabled in a WebView by default. You can enable it through the WebSettings attached to your WebView . You can retrieve WebSettings with getSettings() , then enable JavaScript with setJavaScriptEnabled() . WebView myWebView = (WebView) findViewById(R.
Modify src/MainActivity. java file to add WebView code. Run the application and choose a running android device and install the application on it and verify the results. Following is the content of the modified main activity file src/MainActivity.
Launch an url in an external browser app from your app. startActivity(new Intent(Intent. ACTION_VIEW, Uri.
You are trying to access webview DOM model before it was created.
Wrap your JavaApp related code to the page load listener to achieve your goal:
webEngine.getLoadWorker().stateProperty().addListener(new ChangeListener<Worker.State>() {
@Override
public void changed(ObservableValue<? extends State> ov, State t, State t1) {
if (t1 == Worker.State.SUCCEEDED) {
JSObject window = (JSObject) webEngine.executeScript("window");
window.setMember("app", new JavaApp());
}
}
});
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
