Show gif animation popup while processing in JAVAFX - javafx

Question

I have a method inside of one of my controllers that requires some seconds to process. I would like to have a gif animation popup while this occurs but I only get a static image. This is my code:
#FXML
public void search(ActionEvent e) {
final Stage dialog = new Stage();
Group popup = new Group();
Image image = new Image("file:resources/images/bender.gif");
ImageView view = new ImageView(image);
popup.getChildren().add(view);
Scene dialogScene = new Scene(popup);
dialog.setScene(dialogScene);
dialog.show();
Platform.runLater(new Runnable() {
#Override
public void run() {
Match msg = stablishSearchConditions();
TreeItem<String> root = new TreeItem<>("ROOT");
int indexName = 1;
String mensaje = "Mensaje ";
treeLabelResults.setText("");
arbol.setRoot(root);
for (Match message : msg.each()) {
TreeItem<String> nodo = new TreeItem<String>(mensaje + indexName);
root.getChildren().add(nodo);
root.setExpanded(true);
String mens = message.getMessage();
TreeItem<String> nodo2 = new TreeItem<String>(mens);
nodo.getChildren().add(nodo2);
indexName++;
}
dialog.close();
}
});
}

Answer 1

You are blocking the fx application thread by running the expensive operation on this thread. This prevents your UI from updating, including animating the GIF.
Move the expensive operations to a non-application thread instead and only use Platform.runLater() to "commit" the ui updates:
Runnable expensiveTask = () -> {
// expensive operations that should not run on the application thread
Match msg = stablishSearchConditions();
TreeItem<String> root = new TreeItem<>("ROOT");
int indexName = 1;
String mensaje = "Mensaje ";
for (Match message : msg.each()) {
TreeItem<String> nodo = new TreeItem<String>(mensaje + indexName);
root.getChildren().add(nodo);
root.setExpanded(true);
String mens = message.getMessage();
TreeItem<String> nodo2 = new TreeItem<String>(mens);
nodo.getChildren().add(nodo2);
indexName++;
}
// update ui -> application thread
Platform.runLater(() -> {
treeLabelResults.setText("");
arbol.setRoot(root);
dialog.close();
});
};
// start new thread for expensiveTask
new Thread(expensiveTask).start();