combobox - How to make JavaFX editable comboBox opened?

Question

How to open ComboBox automatically?

I have an editable ComboBox. I want it to be opened automatically, without forcing a user to click on it. How can it be done? I've tried to make something like this:

testButton.fireEvent(new Event(ComboBox.ON_SHOWN));

But it does not work as I need: in the output I can see messages which signals that ON_SHOWN event was fired, but graphically my comboBox is still closed. Also, i've tried

testButton.fireEvent(new Event(ComboBox.ON_SHOWING));

but this shows no reaction at all. As well as

testButton.fireEvent(new Event(ComboBoxBase.ON_SHOWING));

and

testButton.fireEvent(new Event(ComboBoxBase.ON_SHOWN));

PS: saying opened comboBox I mean something like this:

Answer 1

尝试

Button btn = new Button("Show combobox");
btn.setOnAction(new EventHandler<ActionEvent>() {
    @Override
    public void handle(ActionEvent event) {
        comboBox.show();
    }
});

Answer 2

show();方法不适用于CheckComboBox。

请让我们知道如何为 CheckComboBox 做同样的事情。

单击按钮时，CheckComboBox 应自动打开