ZK Spreadsheet Essentials/Working with ZK Spreadsheet/Implement ZK Spreadsheet Event Listeners/Key Events

Users can write key event listeners for key events such as ctrl+C, ctrl+V and so on.

Purpose

Implement onCtrlKey event listener.

Key event

Key event represents a key pressed by user.

• onCtrlKey - This event is fired when user presses a key along with a ctrl key. Event listeners are provided with org.zkoss.zk.ui.event.KeyEvent in the event listener.

Registering Key Events

Key event can be registered to ZK Spreadsheet by calling AbstractComponent.addEventListener(String, EventListener) as shown below.

...
ss.addEventListener(org.zkoss.zk.ui.event.Events.ON_CTRL_KEY,
		new EventListener() {
			public void onEvent(Event event) throws Exception {
				doCtrlKeyEvent((KeyEvent) event);
			}
		});
...

Note: Here instead of onCtrlKey a corresponding static constant declared in org.zkoss.zk.ui.event.Events class is used.

Example

Here is a sample example ZUL file.

<?page title="ZSS" contentType="text/html;charset=UTF-8"?>
<zk>
	<window title="ZSS Key Events" border="normal" width="100%"
		height="100%" apply="org.zkoss.zss.example.KeyEventComposer">
		<hlayout>
		<label value="Edit Box:"></label>
		<textbox id="editBox"></textbox>
		</hlayout>
		<spreadsheet id="ss" width="800px" height="800px" maxrows="20"
			maxcolumns="10" src="/test2/xls/key.xlsx" ctrlKeys="^c^x^v">
		</spreadsheet>
	</window>
</zk>

In your composer.

public class KeyEventComposer extends GenericForwardComposer {

	private transient Spreadsheet ss;
	private transient Textbox editBox;

	public void doAfterCompose(Component comp) throws Exception {
		super.doAfterCompose(comp);
		ss.addEventListener(org.zkoss.zk.ui.event.Events.ON_CTRL_KEY,
				new EventListener() {
					public void onEvent(Event event) throws Exception {
						doCtrlKeyEvent((KeyEvent) event);
					}
				});
	}

	private void doCtrlKeyEvent(KeyEvent event) {
		editBox.setValue("" + event.getKeyCode());
		char c = (char) event.getKeyCode();
		switch (c) {
		case 'X':
			// do cut operation
			break;
		case 'C':
			// do copy operation
			break;
		case 'V':
			// do paste operation
			break;
		default:
			return;
		}
	}

You can retrieve key pressed from KeyEvent using getKeyCode().

Version History

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All source code listed in this book is at Github.