/*
* Copyright 2000-2016 Vaadin Ltd.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package com.vaadin.ui;
import java.util.Collections;
import java.util.Iterator;
import java.util.Objects;
import java.util.Optional;
import com.vaadin.server.ErrorMessage;
import com.vaadin.server.Resource;
import com.vaadin.shared.composite.CompositeState;
import com.vaadin.shared.ui.ContentMode;
/**
* Composite allows creating new UI components by composition of existing
* server-side components.
* <p>
* A composite is created by extending the Composite class and setting the
* composition root component using {@link #setCompositionRoot(Component)}.
* </p>
* <p>
* The composition root itself can contain more components. The advantage of
* wrapping it in a composite is that the details of the composition root, such
* as its public API, are hidden from the users of the composite.
* </p>
* <p>
* A composite itself does not contribute to the DOM in any way (contrary to
* {@link CustomComponent} which adds a {@code <div>} to the DOM.
* </p>
*
* @author Vaadin Ltd.
* @since 8.1
*/
public class Composite extends AbstractComponent implements HasComponents {
private static final String COMPOSITE_HAS_NO_DOM_OR_WIDGET = "A composite has no DOM or widget";
/**
* The contained component.
*/
private Component root = null;
/**
* Constructs a new empty composite.
* <p>
* Use {@link #setCompositionRoot(Component)} to define the contents of the
* composite.
*/
public Composite() {
}
/**
* Constructs a new composite containing the given component.
*
* @param compositionRoot
* the root of the composition component tree. It must not be
* null.
*/
public Composite(AbstractComponent compositionRoot) {
this();
Objects.requireNonNull(compositionRoot);
setCompositionRoot(compositionRoot);
}
/**
* Returns the composition root.
*
* @return the Component Composition root.
*/
protected Component getCompositionRoot() {
return root;
}
/**
* Sets the component contained in the composite.
* <p>
* You must set the composition root to a non-null value before the
* component can be used. It cannot be changed.
* </p>
*
* @param compositionRoot
* the root of the composition component tree.
*/
protected void setCompositionRoot(Component compositionRoot) {
if (root != null) {
throw new IllegalStateException(
"Composition root cannot be changed");
}
if (compositionRoot == null) {
throw new IllegalArgumentException(
"Composition root cannot be null");
}
// set new component
if (compositionRoot.getParent() != null) {
// If the component already has a parent, try to remove it
AbstractSingleComponentContainer.removeFromParent(compositionRoot);
}
compositionRoot.setParent(this);
root = compositionRoot;
markAsDirty();
}
/* Basic component features ------------------------------------------ */
@Override
public Iterator<Component> iterator() {
if (getCompositionRoot() != null) {
return Collections.singletonList(getCompositionRoot()).iterator();
} else {
return Collections.<Component> emptyList().iterator();
}
}
/**
* Gets the number of contained components.
*
* @return the number of contained components (zero or one)
*/
public int getComponentCount() {
return (getCompositionRoot() != null ? 1 : 0);
}
@Override
protected CompositeState getState() {
return (CompositeState) super.getState();
}
@Override
protected CompositeState getState(boolean markAsDirty) {
return (CompositeState) super.getState(markAsDirty);
}
@Override
public void beforeClientResponse(boolean initial) {
super.beforeClientResponse(initial);
if (getComponentCount() != 1) {
throw new IllegalStateException(
"A composite must always have a composition root");
}
}
@Override
public String getStyleName() {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
@Override
public void setStyleName(String style) {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
@Override
public void setStyleName(String style, boolean add) {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
@Override
public void addStyleName(String style) {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
@Override
public void removeStyleName(String style) {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
@Override
public String getPrimaryStyleName() {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
@Override
public void setPrimaryStyleName(String style) {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
private Component getRootOrThrow() {
return Optional.ofNullable(getCompositionRoot())
.orElseThrow(() -> new IllegalStateException(
"Composition root has not been set"));
}
@Override
public float getWidth() {
return getRootOrThrow().getWidth();
}
@Override
public float getHeight() {
return getRootOrThrow().getHeight();
}
@Override
public Unit getWidthUnits() {
return getRootOrThrow().getWidthUnits();
}
@Override
public Unit getHeightUnits() {
return getRootOrThrow().getHeightUnits();
}
@Override
public void setHeight(String height) {
getRootOrThrow().setHeight(height);
}
@Override
public void setWidth(float width, Unit unit) {
getRootOrThrow().setWidth(width, unit);
}
@Override
public void setHeight(float height, Unit unit) {
getRootOrThrow().setHeight(height, unit);
}
@Override
public void setWidth(String width) {
getRootOrThrow().setWidth(width);
}
@Override
public void setSizeFull() {
getRootOrThrow().setSizeFull();
}
@Override
public void setSizeUndefined() {
getRootOrThrow().setSizeUndefined();
}
@Override
public void setWidthUndefined() {
getRootOrThrow().setWidthUndefined();
}
@Override
public void setHeightUndefined() {
getRootOrThrow().setHeightUndefined();
}
@Override
public void setId(String id) {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
@Override
public String getId() {
// Design.read relies on being able to call this
return null;
}
@Override
public void setDebugId(String id) {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
@Override
public String getDebugId() {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
@Override
public String getCaption() {
// Design.read relies on being able to call this
return null;
}
@Override
public void setCaption(String caption) {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
@Override
public void setCaptionAsHtml(boolean captionAsHtml) {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
@Override
public boolean isCaptionAsHtml() {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
@Override
public Resource getIcon() {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
@Override
public void setIcon(Resource icon) {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
@Override
public String getDescription() {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
@Override
public void setDescription(String description) {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
@Override
public void setDescription(String description, ContentMode mode) {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
@Override
public ErrorMessage getErrorMessage() {
return null;
}
@Override
public ErrorMessage getComponentError() {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
@Override
public void setComponentError(ErrorMessage componentError) {
throw new UnsupportedOperationException(COMPOSITE_HAS_NO_DOM_OR_WIDGET);
}
}