How to disable the arrow button in JavaFX combo box - javafx

Question

I have a project I am working on. I am trying to make a dictionary. For that, I have a .csv file with about 55000 words.I am using the trie data structure which has a startsWith() method which checks whether there is a word in the .csv file which matches the given prefix. I had managed to get it to work to find all words that match the given prefix and display them. Now, I have to develop this into a JavaFX app.
So, I thought of using a ComboBox which has its editable attribute set to true so that I could type into it and then the handler associated with the textProperty() of its editor would display all the words starting with given prefix in the listview of the combobox.
Now, the problem I have is that whenever I click the arrow button of the combobox the application stops responding (I think it's because the list view tries to resize itself to fit the items which are 55000).
So, what I want to know is how to disable the arrow button entirely. I have tried to set its background-color to transparent but even then it can still be clicked I want to make it so that it is disabled and transparent basically the combobox ends up looking like a text field.
If there are better, more efficient ways of implementing a dictionary I would appreciate it if you could guide me.

Answer 1

The ListView is a virtual control that only shows a certain number of cells at a time, it doesn't need to "resize itself to the number of items" in any way that would lock up your GUI.
Does this demo program do what you want?
public class Main extends Application {
public static void main(String[] args) throws IOException, URISyntaxException {
launch(args);
}
#Override
public void start(Stage stage) {
List<String> rawWords = Collections.emptyList();
try {
URI wordURI = new URI("https://www-cs-faculty.stanford.edu/~knuth/sgb-words.txt");
BufferedReader reader = new BufferedReader(new InputStreamReader(wordURI.toURL().openStream(), StandardCharsets.UTF_8));
rawWords = reader.lines().collect(Collectors.toCollection(() -> new ArrayList<>(6000)));
} catch (IOException | URISyntaxException ex) {
Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
}
// make the list at least as big as in the question
while(rawWords.size() < 55000) {
ArrayList<String> nextWords = new ArrayList<>(rawWords.size() * 2);
nextWords.addAll(rawWords);
nextWords.addAll(rawWords);
rawWords = nextWords;
}
Collections.sort(rawWords);
ObservableList<String> wordList = FXCollections.observableArrayList(rawWords);
FilteredList<String> filteredList = new FilteredList<>(wordList);
ComboBox<String> combo = new ComboBox<>(filteredList);
combo.setEditable(true);
combo.getEditor().textProperty().addListener((obs, oldVal, newVal) -> {
filteredList.setPredicate(s -> newVal == null || newVal.isEmpty() || s.startsWith(newVal));
});
VBox vbox = new VBox(8,new Label("Dictionary ComboBox"),
combo,
new Label("\n\n\n\nThis space intentionally left blank.\n\n\n\n"));
vbox.setPadding(new Insets(8));
Scene scene = new Scene(vbox, 400, 300);
stage.setTitle("Demo - Filtered Combobox List");
stage.setScene(scene);
stage.show();
}
}