org.metawidget.faces.renderkit.html.HtmlLayoutRenderer Maven / Gradle / Ivy
// Metawidget (licensed under LGPL)
//
// This library 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 library 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 library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
package org.metawidget.faces.renderkit.html;
import static org.metawidget.inspector.InspectionResultConstants.*;
import java.io.IOException;
import java.util.List;
import java.util.Map;
import javax.faces.component.UICommand;
import javax.faces.component.UIComponent;
import javax.faces.component.UIInput;
import javax.faces.component.UIOutput;
import javax.faces.component.UIParameter;
import javax.faces.component.html.HtmlInputHidden;
import javax.faces.component.html.HtmlMessage;
import javax.faces.component.html.HtmlOutputLabel;
import javax.faces.context.FacesContext;
import javax.faces.context.ResponseWriter;
import javax.faces.render.Renderer;
import org.metawidget.faces.FacesUtils;
import org.metawidget.faces.component.UIMetawidget;
import org.metawidget.faces.component.UIStub;
import org.metawidget.util.simple.SimpleLayoutUtils;
import org.metawidget.util.simple.StringUtils;
/**
* Base class for all JSF HTML layout renderers. This implementation recognizes the following
* <f:param> parameters:
*
*
* inlineMessages - whether to wrap input components with inline <h:message>
* tags. True by default
* messageStyle
* messageStyleClass
* labelSuffix
*
*
* @author Richard Kennard
*/
public abstract class HtmlLayoutRenderer
extends Renderer {
//
// Private statics
//
private static final String LABEL_ID_SUFFIX = "-label";
//
// Public methods
//
@Override
public void encodeBegin( FacesContext context, UIComponent metawidgetComponent )
throws IOException {
UIMetawidget metawidget = (UIMetawidget) metawidgetComponent;
metawidget.putClientProperty( HtmlLayoutRenderer.class, null );
super.encodeBegin( context, metawidget );
// Determine label suffix
State state = getState( metawidget );
state.labelSuffix = metawidget.getParameter( "labelSuffix" );
// Using inline messages?
String inlineMessagesParameter = metawidget.getParameter( "inlineMessages" );
if ( inlineMessagesParameter != null ) {
state.inlineMessages = Boolean.valueOf( inlineMessagesParameter );
}
// Message styles
state.messageStyle = metawidget.getParameter( "messageStyle" );
state.messageStyleClass = metawidget.getParameter( "messageStyleClass" );
}
/**
* Denotes that this Renderer renders its own children (eg. JSF should not call
* encodeBegin on each child for us)
*/
@Override
public boolean getRendersChildren() {
return true;
}
//
// Protected methods
//
protected String getLabelText( UIComponent componentNeedingLabel ) {
@SuppressWarnings( "unchecked" )
Map metadataAttributes = (Map) componentNeedingLabel.getAttributes().get( UIMetawidget.COMPONENT_ATTRIBUTE_METADATA );
return ( (UIMetawidget) componentNeedingLabel.getParent() ).getLabelString( metadataAttributes );
}
/**
* Render the label text. Rendering is done via an HtmlOutputText renderer, so that
* it is properly escaped. Any JSF EL expressions embedded in the label should have already been
* evaluated by FacesInspectionResultProcessor.
*
* @return whether a label was written
*/
protected boolean layoutLabel( FacesContext context, UIComponent metawidget, UIComponent componentNeedingLabel )
throws IOException {
// Generally speaking, UICommands are their own label (ie. the text on a button)
//
// In cases where a component is defined as a UICommand but you *do* still want a label
// (e.g. the RichFaces ProgressBar), consider wrapping the component in a Stub.
if ( componentNeedingLabel instanceof UICommand ) {
return false;
}
String labelText = getLabelText( componentNeedingLabel );
if ( !SimpleLayoutUtils.needsLabel( labelText, null ) ) {
return false;
}
// Render the label
UIOutput componentLabel = createLabel( context, componentNeedingLabel );
State state = getState( metawidget );
if ( state.labelSuffix == null ) {
state.labelSuffix = StringUtils.SEPARATOR_COLON;
}
// (any embedded expressions should have gotten evaluated by FacesInspectionResultProcessor)
componentLabel.setValue( labelText + state.labelSuffix );
FacesUtils.render( context, componentLabel );
return true;
}
/**
* Create a label component for the given UIComponent. Clients may override this
* method to create a different type of label component.
*/
protected UIOutput createLabel( FacesContext context, UIComponent componentNeedingLabel ) {
HtmlOutputLabel componentLabel = (HtmlOutputLabel) context.getApplication().createComponent( HtmlOutputLabel.COMPONENT_TYPE );
if ( componentNeedingLabel instanceof UIStub ) {
// Not setFor on UIStub, because stubs never render id. However we can take a guess if
// there's only one child component
if ( componentNeedingLabel.getChildren().size() == 1 ) {
componentLabel.setFor( componentNeedingLabel.getChildren().get( 0 ).getId() );
}
} else if ( componentNeedingLabel.getId() != null ) {
componentLabel.setFor( componentNeedingLabel.getId() );
}
// Call .setParent before .setId to avoid 'unable to find component with id' warning and/or
// 'duplicate component' error (depending on the JSF implementation)
if ( componentLabel.getFor() != null ) {
componentLabel.setParent( componentNeedingLabel.getParent() );
componentLabel.setId( componentLabel.getFor() + LABEL_ID_SUFFIX );
}
return componentLabel;
}
protected void layoutChild( FacesContext context, UIComponent metawidget, UIComponent childComponent )
throws IOException {
FacesUtils.render( context, childComponent );
// No need for inline messages?
if ( childComponent instanceof HtmlInputHidden ) {
return;
}
String messageFor = childComponent.getId();
if ( childComponent instanceof UIMetawidget ) {
// (drill into single component UIMetawidgets)
UIComponent childOfChild = null;
for ( UIComponent child : childComponent.getChildren() ) {
if ( child instanceof UIParameter ) {
continue;
}
if ( childOfChild != null ) {
return;
}
childOfChild = child;
}
if ( childOfChild == null ) {
return;
}
messageFor = childOfChild.getId();
} else if ( !( childComponent instanceof UIInput ) ) {
return;
}
@SuppressWarnings( "unchecked" )
Map metadataAttributes = (Map) childComponent.getAttributes().get( UIMetawidget.COMPONENT_ATTRIBUTE_METADATA );
if ( metadataAttributes != null ) {
if ( TRUE.equals( metadataAttributes.get( READ_ONLY ) ) || ( (UIMetawidget) metawidget ).isReadOnly() ) {
return;
}
}
// Not using inline messages?
State state = getState( metawidget );
if ( !state.inlineMessages ) {
return;
}
// Render inline message
//
// Temporarily create an HtmlMessage and render it. It needs a parent to be able to render,
// so add it/remove it again from the Metawidget. Do not call setParent directly, as
// cautioned here:
//
// http://javaserverfaces.java.net/nonav/docs/2.0/javadocs/javax/faces/component/UIComponent.html#setParent(javax.faces.component.UIComponent)
List children = metawidget.getChildren();
UIComponent inlineMessage = createInlineMessage( context, metawidget, messageFor );
try {
children.add( inlineMessage );
FacesUtils.render( context, inlineMessage );
} finally {
children.remove( inlineMessage );
}
}
/**
* Creates an inline HtmlMessage attached to the given messageFor id.
*
* Subclasses can override this method to create a different messaging object, such as an
* HtmlMessages (with an 's').
*/
protected UIComponent createInlineMessage( FacesContext context, UIComponent metawidget, String messageFor ) {
HtmlMessage message = (HtmlMessage) context.getApplication().createComponent( HtmlMessage.COMPONENT_TYPE );
message.setId( FacesUtils.createUniqueId() );
message.setFor( messageFor );
// Parse styles
State state = getState( metawidget );
FacesUtils.setStyleAndStyleClass( message, state.messageStyle, state.messageStyleClass );
return message;
}
protected void writeStyleAndClass( UIMetawidget metawidget, ResponseWriter writer, String style )
throws IOException {
String styleParameter = metawidget.getParameter( style + "Style" );
if ( styleParameter != null ) {
writer.writeAttribute( "style", styleParameter, "style" );
}
String styleClassParameter = metawidget.getParameter( style + "StyleClass" );
if ( styleClassParameter != null ) {
writer.writeAttribute( "class", styleClassParameter, "class" );
}
}
//
// Private methods
//
private State getState( UIComponent metawidget ) {
State state = (State) ( (UIMetawidget) metawidget ).getClientProperty( HtmlLayoutRenderer.class );
if ( state == null ) {
state = new State();
( (UIMetawidget) metawidget ).putClientProperty( HtmlLayoutRenderer.class, state );
}
return state;
}
//
// Inner class
//
/**
* Simple, lightweight structure for saving state.
*/
/* package private */static class State {
/* package private */boolean inlineMessages = true;
/* package private */String messageStyle;
/* package private */String messageStyleClass;
/* package private */String labelSuffix;
}
}