vaadin-framework/src/com/itmill/toolkit/terminal/gwt/client/ui/IOptionGroupBase.java

package com.itmill.toolkit.terminal.gwt.client.ui;

import java.util.Set;

import com.google.gwt.user.client.ui.ChangeListener;
import com.google.gwt.user.client.ui.ClickListener;
import com.google.gwt.user.client.ui.Composite;
import com.google.gwt.user.client.ui.FlowPanel;
import com.google.gwt.user.client.ui.KeyboardListener;
import com.google.gwt.user.client.ui.Panel;
import com.google.gwt.user.client.ui.Widget;
import com.itmill.toolkit.terminal.gwt.client.ApplicationConnection;
import com.itmill.toolkit.terminal.gwt.client.Paintable;
import com.itmill.toolkit.terminal.gwt.client.UIDL;

abstract class IOptionGroupBase extends Composite implements Paintable,
		ClickListener, ChangeListener, KeyboardListener {

	public static final String CLASSNAME_OPTION = "i-select-option";

	ApplicationConnection client;

	String id;

	protected boolean immediate;

	protected Set selectedKeys;

	protected boolean multiselect;

	protected boolean disabled;

	protected boolean readonly;

	/**
	 * Widget holding the different options (e.g. ListBox or Panel for radio
	 * buttons) (optional, fallbacks to container Panel)
	 */
	protected Widget optionsContainer;

	/**
	 * Panel containing the component
	 */
	private Panel container;

	private ITextField newItemField;

	private IButton newItemButton;

	public IOptionGroupBase(String classname) {
		container = new FlowPanel();
		initWidget(container);
		optionsContainer = container;
		container.setStyleName(classname);
		immediate = false;
		multiselect = false;
	}

	/*
	 * Call this if you wish to specify your own container for the option
	 * elements (e.g. SELECT)
	 */
	public IOptionGroupBase(Widget w, String classname) {
		this(classname);
		optionsContainer = w;
		container.add(optionsContainer);
	}

	public void updateFromUIDL(UIDL uidl, ApplicationConnection client) {
		this.client = client;
		this.id = uidl.getId();

		if (client.updateComponent(this, uidl, true))
			return;

		selectedKeys = uidl.getStringArrayVariableAsSet("selected");

		readonly = uidl.getBooleanAttribute("readonly");
		disabled = uidl.getBooleanAttribute("disabled");
		multiselect = "multi".equals(uidl.getStringAttribute("selectmode"));
		immediate = uidl.getBooleanAttribute("immediate");

		UIDL ops = uidl.getChildUIDL(0);

		buildOptions(ops);

		if (uidl.getBooleanAttribute("allownewitem")) {
			if (newItemField == null) {
				newItemButton = new IButton();
				newItemButton.setText("+");
				newItemButton.addClickListener(this);
				newItemField = new ITextField();
				newItemField.addKeyboardListener(this);
				newItemField.setColumns(16);
			}
			newItemField.setEnabled(!disabled && !readonly);
			newItemButton.setEnabled(!disabled && !readonly);

			if (newItemField != null && newItemField.getParent() == container)
				return;
			container.add(newItemField);
			container.add(newItemButton);
		} else if (newItemField != null) {
			container.remove(newItemField);
			container.remove(newItemButton);
		}

	}

	public void onClick(Widget sender) {
		if (sender == newItemButton && !newItemField.getText().equals("")) {
			client.updateVariable(id, "newitem", newItemField.getText(), true);
			newItemField.setText("");
		}
	}

	public void onChange(Widget sender) {
		if (multiselect) {
			client
					.updateVariable(id, "selected", getSelectedItems(),
							immediate);
		} else {
			client.updateVariable(id, "selected", new String[] { ""
					+ getSelectedItem() }, immediate);
		}
	}

	public void onKeyPress(Widget sender, char keyCode, int modifiers) {
		if (sender == newItemField && keyCode == KeyboardListener.KEY_ENTER)
			newItemButton.click();
	}

	public void onKeyUp(Widget sender, char keyCode, int modifiers) {
		// Ignore, subclasses may override
	}

	public void onKeyDown(Widget sender, char keyCode, int modifiers) {
		// Ignore, subclasses may override
	}

	protected abstract void buildOptions(UIDL uidl);

	protected abstract Object[] getSelectedItems();

	protected Object getSelectedItem() {
		Object[] sel = getSelectedItems();
		if (sel.length > 0)
			return sel[0];
		else
			return null;
	}

}