org.richfaces.component.AbstractPlaceholder Maven / Gradle / Ivy
/*
* JBoss, Home of Professional Open Source
* Copyright , Red Hat, Inc. and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.richfaces.component;
import javax.el.ValueExpression;
import javax.faces.component.UIComponent;
import javax.faces.component.UIOutput;
import javax.faces.context.FacesContext;
import javax.faces.event.AbortProcessingException;
import javax.faces.event.ComponentSystemEvent;
import javax.faces.event.ListenerFor;
import javax.faces.event.PostAddToViewEvent;
import org.richfaces.cdk.annotations.Attribute;
import org.richfaces.cdk.annotations.JsfComponent;
import org.richfaces.cdk.annotations.JsfRenderer;
import org.richfaces.cdk.annotations.Tag;
import org.richfaces.cdk.annotations.TagType;
import org.richfaces.component.event.PreRenderParentListener;
import org.richfaces.renderkit.PlaceholderRendererBase;
/**
* Adds placeholder capability to HTML input and textarea elements. A placeholder typically appears as light gray text within an
* input or textarea element whenever the element is empty and does not have focus. This provides a hint to the user as to what
* the input or textarea element is used for, or the type of input that is required.
*/
@JsfComponent(tag = @Tag(name = "placeholder", type = TagType.Facelets), renderer = @JsfRenderer(family = AbstractPlaceholder.COMPONENT_FAMILY, type = PlaceholderRendererBase.RENDERER_TYPE), attributes = { "javax.faces.component.ValueHolder.xml" })
@ListenerFor(systemEventClass = PostAddToViewEvent.class)
public abstract class AbstractPlaceholder extends UIOutput {
// ------------------------------ FIELDS ------------------------------
public static final String COMPONENT_FAMILY = "org.richfaces.Placeholder";
public static final String COMPONENT_TYPE = "org.richfaces.Placeholder";
@Attribute(required = true)
public abstract Object getValue();
/**
* The jQuery selector used to filter which child DOM elements will be a placeholder attached to.
*/
@Attribute
public abstract String getSelector();
/**
* Space-separated list of CSS style class(es) which will be applied to the target input component when placeholder is
* active.
*/
@Attribute
public abstract String getStyleClass();
/**
* Registers component for processing before its parent component when it has empty selector - this logic is used as
* workaround for text components which does not render children (RF-12589).
*/
@Override
public void processEvent(ComponentSystemEvent event) throws AbortProcessingException {
if (event.getSource() == this) {
if (event instanceof PostAddToViewEvent) {
// only for nested usage (workaround for RF-12589)
if (this.getSelector() == null || this.getSelector().isEmpty()) {
UIComponent component = ((PostAddToViewEvent) event).getComponent();
UIComponent parent = component.getParent();
new PlaceholderParentPreRenderListener(parent, component);
}
}
}
super.processEvent(event);
}
/**
* Renders component before its parent.
*/
private static class PlaceholderParentPreRenderListener extends PreRenderParentListener {
private static final long serialVersionUID = 1870218106060075543L;
public PlaceholderParentPreRenderListener(UIComponent parent, UIComponent component) {
super(parent, component);
}
@Override
protected void preRenderParent(FacesContext facesContext, UIComponent component) {
AbstractPlaceholder placeholder = (AbstractPlaceholder) component;
UIComponent parent = component.getParent();
PlaceholderRendererBase renderer = (PlaceholderRendererBase) placeholder.getRenderer(facesContext);
if (parent instanceof InplaceComponent) {
if (placeholder.isRendered() && placeholder.getValue() != null) {
// backup defaultLabel attribute
ValueExpression originalExpression = parent.getValueExpression("defaultLabel");
if (originalExpression != null) {
parent.getAttributes().put("originalDefaultLabel", originalExpression);
} else if (((InplaceComponent) parent).getDefaultLabel() != null) {
parent.getAttributes().put("originalDefaultLabel", ((InplaceComponent) parent).getDefaultLabel());
}
String text = renderer.getConvertedValue(facesContext, placeholder);
((InplaceComponent) parent).setDefaultLabel(text);
} else {
Object defaultLabel = parent.getAttributes().get("originalDefaultLabel");
((InplaceComponent) parent).setDefaultLabel(null);
if (defaultLabel instanceof ValueExpression) {
parent.setValueExpression("defaultLabel", (ValueExpression) defaultLabel);
} else if (defaultLabel != null) {
((InplaceComponent) parent).setDefaultLabel((String) defaultLabel);
}
}
} else {
try {
if (component.isRendered()) {
renderer.doEncodeEnd(facesContext.getResponseWriter(), facesContext, component);
}
} catch (Exception e) {
throw new IllegalStateException("Rendering of placeholder before its parent has failed", e);
}
}
}
}
}