brainbaking/content/wiki/code/java/vaadin.md

+++ title = "vaadin" draft = false tags = [ "code", "java", "vaadin" ] date = "2013-03-12" +++

Vaadin 7

Javascript uitvoeren in de frontent

@JavaScript({ "https://ajax.googleapis.com/ajax/libs/jquery/1.9.0/jquery.min.js", "js_label.js" })
public class JsLabel extends AbstractJavaScriptComponent {

	public JsLabel(String xhtml) {
		getState().xhtml = xhtml;
	}

	@Override
	protected JsLabelState getState() {
		return (JsLabelState) super.getState();
	}

	public static class JsLabelState extends JavaScriptComponentState {
		public String xhtml;
	}

}

en bijbehorende js_label.js file - plaats in src/main/resources onder zelfde subdir als package van java file...

be_vdab_nonstop_presentation_form_JsLabel = function() {
  var e = this.getElement();
	
  this.onStateChange = function() {
    jQuery(e).html(this.getState().xhtml); 
  }
}

MainUI

@PreserveOnRefresh
@Theme("yourTheme")
public class MainUI extends UI {
	@Override
	protected final void init(VaadinRequest request) {
		setNavigator(new MyNavigator(this));
		initDefaultScreen();
		getNavigator().navigate();
	}

	private void initDefaultScreen() {
		getNavigator().addView("", BlahScherm.class);
	}

	public void refresh() {
		Component content = getContent();
		setContent(new VerticalLayout());
		setContent(content);
	}

}

Waarbij BlahScherm View implementeert (extends CustomComponent)

Parameters van de URL afhalen en afhankelijk daarvan ergens naar navigeren kan gebeuren in MyNavigator die extends Navigator. In de constructor addView() aanroepen (keyvalue pair)

Utilities om in componenten te zoeken

public class VaadinUtilties {

	public static <T extends AbstractComponent> T findComponentWithin(HasComponents otherComponent, Class<T> componentClass, String id) {
		return findOnly(otherComponent, componentClass, metId(id));
	}

	public static <E extends Component> E findOnly(HasComponents container, final Class<E> componentClass, Predicate<? super E> predicate) {
		return getOnlyElement(filter(findAll(container, componentClass), predicate));
	}

	public static <E extends Component> E findOnly(HasComponents container, final Class<E> componentClass) {
		return findOnly(container, componentClass, alwaysTrue());
	}

	public static <E extends Component> Set<E> findAll(HasComponents container, Class<E> componentClass) {
		if (container instanceof CustomField) {
			initCustomField((CustomField<?>) container);
		}
		Set<E> result = newHashSet(filter(container, componentClass));
		for (HasComponents subContainer : filter(container, HasComponents.class)) {
			result.addAll(findAll(subContainer, componentClass));
		}
		return result;
	}

	public static void initCustomField(CustomField<?> customField) {
		customField.iterator().next();
	}

	public static boolean isVisibleOnScreen(Component component) {
		return component.isVisible() && parentIsVisible(component);
	}

	private static boolean parentIsVisible(Component component) {
		if (component.getParent() ###### null) {
			return true;
		} else {
			return isVisibleOnScreen(component.getParent());
		}
	}

	public static Predicate<Component> metCaption(final String caption) {
		return new Predicate<Component>() {
			public boolean apply(Component component) {
				return StringUtils.equals(component.getCaption(), caption);
			}
		};
	}

	public static Predicate<Component> captionContains(final String caption) {
		return new Predicate<Component>() {
			public boolean apply(Component component) {
				return StringUtils.contains(component.getCaption(), caption);
			}
		};
	}

	public static Predicate<Label> value(final String value) {
		return new Predicate<Label>() {
			public boolean apply(Label label) {
				return StringUtils.equals(label.getValue(), value);
			}
		};
	}

	public static Predicate<Label> valueContains(final String value) {
		return new Predicate<Label>() {
			public boolean apply(Label label) {
				return StringUtils.contains(label.getValue(), value);
			}
		};
	}

	public static Predicate<Component> metId(final String id) {
		return new Predicate<Component>() {
			public boolean apply(Component component) {
				return StringUtils.equals(component.getId(), id);
			}
		};
	}

}