Main.java Source code

Introduction

Here is the source code for Main.java

Source

import java.awt.BorderLayout;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;

import javax.swing.ComboBoxEditor;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.plaf.basic.BasicComboBoxEditor;

public class Main {
    public static void main(String[] args) {
        JFrame fr = new JFrame();
        JPanel p = new JPanel();
        p.setLayout(new BorderLayout());
        String[] ss = new String[] { "112", "1223", "1124", "1134" };
        fr.getContentPane().add(p);
        AutoCompleteComboBox cb = new AutoCompleteComboBox(ss);

        p.add("South", cb);
        p.add("Center", new JButton("test combo box"));
        fr.pack();
        fr.setVisible(true);
    }
}

class AutoCompleteComboBox extends JComboBox {
    public int caretPos = 0;
    public JTextField tf = null;

    public AutoCompleteComboBox(final Object items[]) {
        super(items);
        this.setEditor(new BasicComboBoxEditor());
        this.setEditable(true);
    }

    public void setSelectedIndex(int ind) {
        super.setSelectedIndex(ind);
        tf.setText(getItemAt(ind).toString());
        tf.setSelectionEnd(caretPos + tf.getText().length());
        tf.moveCaretPosition(caretPos);
    }

    public void setEditor(ComboBoxEditor anEditor) {
        super.setEditor(anEditor);
        if (anEditor.getEditorComponent() instanceof JTextField) {
            tf = (JTextField) anEditor.getEditorComponent();
            tf.addKeyListener(new KeyAdapter() {
                public void keyReleased(KeyEvent ev) {
                    char key = ev.getKeyChar();
                    if (!(Character.isLetterOrDigit(key) || Character.isSpaceChar(key))) {
                        return;
                    }
                    String s = tf.getText();
                    caretPos = tf.getCaretPosition();
                    try {
                        String text = tf.getText(0, caretPos);
                        int n = getItemCount();
                        for (int i = 0; i < n; i++) {
                            int ind = ((String) getItemAt(i)).indexOf(text);
                            if (ind == 0) {
                                setSelectedIndex(i);
                                return;
                            }
                        }
                    } catch (Exception ex) {
                        ex.printStackTrace();
                    }
                }
            });
        }
    }
}