Example usage for javax.swing.plaf ComboBoxUI isPopupVisible

Introduction

In this page you can find the example usage for javax.swing.plaf ComboBoxUI isPopupVisible.

Prototype

public abstract boolean isPopupVisible(JComboBox<?> c);

Source Link

Document

Determine the visibility of the popup

Usage

From source file:Main.java

public void actionPerformed(ActionEvent e) {
    JComboBox jcb = (JComboBox) e.getSource();
    System.out.println("down action");
    ComboBoxUI ui = jcb.getUI();

    if (ui.isPopupVisible(jcb)) {
        int i = jcb.getSelectedIndex();
        if (i < jcb.getModel().getSize() - 1) {
            jcb.setSelectedIndex(i + 1);
            jcb.repaint();/*from  www .  j ava  2 s.  c o  m*/
        }
    } else {
        int nItems = jcb.getItemCount();

        ComboBoxEditor cbe = jcb.getEditor();

        String st; // Search text

        st = ((String) cbe.getItem()).toUpperCase();

        for (int i = 0; i < nItems; i++) {
            String item = ((String) jcb.getItemAt(i)).toUpperCase();

            if (item.startsWith(st)) {
                jcb.setSelectedIndex(i);
                break;
            }
        }

        ui.setPopupVisible(jcb, true);
    }
}

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