MultiKey Combo : ComboBox « Swing JFC « Java

1. Java
2. Swing JFC
3. ComboBox

MultiKey Combo

  
/*
Definitive Guide to Swing for Java 2, Second Edition
By John Zukowski     
ISBN: 1-893115-78-X
Publisher: APress
*/

import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;

import javax.swing.ComboBoxModel;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.Timer;

public class MultiKeyCombo {
  public static void main(String args[]) {
    String labels[] = { "One", "Only", "Once", "Okay", "oneself",
        "onlooker", "Onslaught", "Onyx", "onus", "onward" };
    JFrame f = new JFrame("Example JList");
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JComboBox jc = new JComboBox(labels);
    MultiKeySelectionManager mk = new MultiKeySelectionManager();
    jc.setKeySelectionManager(mk);
    //    jc.setKeySelectionManager (new JComboBox.KeySelectionManager() {
    //      public int selectionForKey (char aKey, ComboBoxModel aModel) {
    //        return -1;
    //      }
    //    });
    Container c = f.getContentPane();
    c.add(jc, BorderLayout.NORTH);
    f.setSize(200, 200);
    f.setVisible(true);
  }
}

class MultiKeySelectionManager implements JComboBox.KeySelectionManager {
  private StringBuffer currentSearch = new StringBuffer();

  private Timer resetTimer;

  private final static int RESET_DELAY = 3000;

  public MultiKeySelectionManager() {
    resetTimer = new Timer(RESET_DELAY, new ActionListener() {
      public void actionPerformed(ActionEvent actionEvent) {
        currentSearch.setLength(0);
      }
    });
  }

  public int selectionForKey(char aKey, ComboBoxModel aModel) {
    // Reset if invalid character
    if (aKey == KeyEvent.CHAR_UNDEFINED) {
      currentSearch.setLength(0);
      return -1;
    }
    // Since search, don't reset search
    resetTimer.stop();
    // Convert input to uppercase
    char key = Character.toUpperCase(aKey);
    // Build up search string
    currentSearch.append(key);
    // Find selected position within model to starting searching from
    Object selectedElement = aModel.getSelectedItem();
    int selectedIndex = -1;
    if (selectedElement != null) {
      for (int i = 0, n = aModel.getSize(); i < n; i++) {
        if (aModel.getElementAt(i) == selectedElement) {
          selectedIndex = i;
          break;
        }
      }
    }
    boolean found = false;
    String search = currentSearch.toString();
    // Search from selected forward, wrap back to beginning if not found
    for (int i = 0, n = aModel.getSize(); i < n; i++) {
      String element = aModel.getElementAt(selectedIndex).toString()
          .toUpperCase();
      if (element.startsWith(search)) {
        found = true;
        break;
      }
      selectedIndex++;
      if (selectedIndex == n) {
        selectedIndex = 0; // wrap
      }
    }
    // Restart timer
    resetTimer.start();
    return (found ? selectedIndex : -1);
  }
}

           
         
    
  

Related examples in the same category

1.	Combobox combines a button or editable field and a drop-down list.
2.	Using drop-down lists
3.	A fancy example of JComboBox with a custom renderer and editor
4.	Editable ComboBox
5.	Create a simple combobox
6.	Font Chooser ComboBox
7.	Color combobox renderer
8.	Select the combobox by choose the nearby label
9.	ComoboBox loads and saves items automatically from a file
10.	Sharing a Model between a JList and JComboBox
11.	ComboBox Demo 2
12.	Custom ComboBox with Image
13.	ComboBox Demo
14.	List: Shared Data Sample
15.	Selecting Combo Sample
16.	PopupCombo Sample
17.	Dual Sample: JList and ComboBox
18.	ComboBox Sample
19.	Color ComboBox: ComboBoxEditor Demo
20.	Determining When the Menu of a JComboBox Component Is Displayed
21.	Listening for Action Events from a JComboBox Component
22.	Listening for Changes to the Selected Item in a JComboBox Component
23.	Setting the Number of Visible Items in the Menu of a JComboBox Component
24.	Displaying the Menu in a JComboBox Component Using a Keystroke If the Selected Item Is Not Unique
25.	Displaying the Menu in a JComboBox Component Using a Keystroke
26.	Determining If the Menu of a JComboBox Component Is Visible
27.	Selecting an Item in a JComboBox Component with Multiple Keystrokes
28.	Adding and Removing an Item in a JComboBox Component
29.	Add an item after the first item
30.	Add an item to the end of the list
31.	Remove first item
32.	Remove the last item
33.	Remove all items
34.	Getting the Items in a JComboBox Component
35.	Getting and Setting the Selected Item in a JComboBox Component
36.	If the combobox is editable, the new value can be any value
37.	Creating a read-only and editable JComboBox Component
38.	ArrayListComboBoxModel Demo
39.	A frame with a sample text label and a combo box for selecting font faces