/*
* Copyright 2010 IT Mill 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.lang.reflect.Method;
import com.vaadin.data.Property;
import com.vaadin.data.util.ObjectProperty;
import com.vaadin.terminal.PaintException;
import com.vaadin.terminal.PaintTarget;
import com.vaadin.terminal.gwt.client.ui.VLabel;
/**
* Label component for showing non-editable short texts.
*
* The label content can be set to the modes specified by the final members
* CONTENT_*
*
* <p>
* The contents of the label may contain simple formatting:
* <ul>
* <li><b><b></b> Bold
* <li><b><i></b> Italic
* <li><b><u></b> Underlined
* <li><b><br/></b> Linebreak
* <li><b><ul><li>item 1</li><li>item 2</li></ul></b> List of
* items
* </ul>
* The <b>b</b>,<b>i</b>,<b>u</b> and <b>li</b> tags can contain all the tags in
* the list recursively.
* </p>
*
* @author IT Mill Ltd.
* @version
* 6.3.4
* @since 3.0
*/
@SuppressWarnings("serial")
@ClientWidget(VLabel.class)
public class Label extends AbstractComponent implements Property,
Property.Viewer, Property.ValueChangeListener,
Property.ValueChangeNotifier, Comparable {
/**
* Content mode, where the label contains only plain text. The getValue()
* result is coded to XML when painting.
*/
public static final int CONTENT_TEXT = 0;
/**
* Content mode, where the label contains preformatted text.
*/
public static final int CONTENT_PREFORMATTED = 1;
/**
* Formatted content mode, where the contents is XML restricted to the UIDL
* 1.0 formatting markups.
*
* @deprecated Use CONTENT_XML instead.
*/
@Deprecated
public static final int CONTENT_UIDL = 2;
/**
* Content mode, where the label contains XHTML. Contents is then enclosed
* in DIV elements having namespace of
* "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd".
*/
public static final int CONTENT_XHTML = 3;
/**
* Content mode, where the label contains well-formed or well-balanced XML.
* Each of the root elements must have their default namespace specified.
*/
public static final int CONTENT_XML = 4;
/**
* Content mode, where the label contains RAW output. Output is not required
* to comply to with XML. In Web Adapter output is inserted inside the
* resulting HTML document as-is. This is useful for some specific purposes
* where possibly broken HTML content needs to be shown, but in most cases
* XHTML mode should be preferred.
*/
public static final int CONTENT_RAW = 5;
/**
* The default content mode is plain text.
*/
public static final int CONTENT_DEFAULT = CONTENT_TEXT;
/** Array of content mode names that are rendered in UIDL as mode attribute. */
private static final String[] CONTENT_MODE_NAME = { "text", "pre", "uidl",
"xhtml", "xml", "raw" };
private static final String DATASOURCE_MUST_BE_SET = "Datasource must be set";
private Property dataSource;
private int contentMode = CONTENT_DEFAULT;
/**
* Creates an empty Label.
*/
public Label() {
this("");
}
/**
* Creates a new instance of Label with text-contents.
*
* @param content
*/
public Label(String content) {
this(content, CONTENT_DEFAULT);
}
/**
* Creates a new instance of Label with text-contents read from given
* datasource.
*
* @param contentSource
*/
public Label(Property contentSource) {
this(contentSource, CONTENT_DEFAULT);
}
/**
* Creates a new instance of Label with text-contents.
*
* @param content
* @param contentMode
*/
public Label(String content, int contentMode) {
this(new ObjectProperty(content, String.class), contentMode);
}
/**
* Creates a new instance of Label with text-contents read from given
* datasource.
*
* @param contentSource
* @param contentMode
*/
public Label(Property contentSource, int contentMode) {
setPropertyDataSource(contentSource);
if (contentMode != CONTENT_DEFAULT) {
setContentMode(contentMode);
}
setWidth(100, UNITS_PERCENTAGE);
}
/**
* Set the component to read-only. Readonly is not used in label.
*
* @param readOnly
* True to enable read-only mode, False to disable it.
*/
@Override
public void setReadOnly(boolean readOnly) {
if (dataSource == null) {
throw new IllegalStateException(DATASOURCE_MUST_BE_SET);
}
dataSource.setReadOnly(readOnly);
}
/**
* Is the component read-only ? Readonly is not used in label - this returns
* allways false.
*
* @return <code>true</code> if the component is in read only mode.
*/
@Override
public boolean isReadOnly() {
if (dataSource == null) {
throw new IllegalStateException(DATASOURCE_MUST_BE_SET);
}
return dataSource.isReadOnly();
}
/**
* Paints the content of this component.
*
* @param target
* the Paint Event.
* @throws PaintException
* if the Paint Operation fails.
*/
@Override
public void paintContent(PaintTarget target) throws PaintException {
if (contentMode != CONTENT_TEXT) {
target.addAttribute("mode", CONTENT_MODE_NAME[contentMode]);
}
if (contentMode == CONTENT_TEXT) {
target.addText(toString());
} else if (contentMode == CONTENT_UIDL) {
target.addUIDL(toString());
} else if (contentMode == CONTENT_XHTML) {
target.startTag("data");
target.addXMLSection("div", toString(),
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd");
target.endTag("data");
} else if (contentMode == CONTENT_PREFORMATTED) {
target.startTag("pre");
target.addText(toString());
target.endTag("pre");
} else if (contentMode == CONTENT_XML) {
target.addXMLSection("data", toString(), null);
} else if (contentMode == CONTENT_RAW) {
target.startTag("data");
target.addAttribute("escape", false);
target.addText(toString());
target.endTag("data");
}
}
/**
* Gets the value of the label. Value of the label is the XML contents of
* the label.
*
* @return the Value of the label.
*/
public Object getValue() {
if (dataSource == null) {
throw new IllegalStateException(DATASOURCE_MUST_BE_SET);
}
return dataSource.getValue();
}
/**
* Set the value of the label. Value of the label is the XML contents of the
* label.
*
* @param newValue
* the New value of the label.
*/
public void setValue(Object newValue) {
if (dataSource == null) {
throw new IllegalStateException(DATASOURCE_MUST_BE_SET);
}
dataSource.setValue(newValue);
}
/**
* @see java.lang.Object#toString()
*/
@Override
public String toString() {
if (dataSource == null) {
throw new IllegalStateException(DATASOURCE_MUST_BE_SET);
}
return dataSource.toString();
}
/**
* Gets the type of the Property.
*
* @see com.vaadin.data.Property#getType()
*/
public Class getType() {
if (dataSource == null) {
throw new IllegalStateException(DATASOURCE_MUST_BE_SET);
}
return dataSource.getType();
}
/**
* Gets the viewing data-source property.
*
* @return the data source property.
* @see com.vaadin.data.Property.Viewer#getPropertyDataSource()
*/
public Property getPropertyDataSource() {
return dataSource;
}
/**
* Sets the property as data-source for viewing.
*
* @param newDataSource
* the new data source Property
* @see com.vaadin.data.Property.Viewer#setPropertyDataSource(com.vaadin.data.Property)
*/
public void setPropertyDataSource(Property newDataSource) {
// Stops listening the old data source changes
if (dataSource != null
&& Property.ValueChangeNotifier.class
.isAssignableFrom(dataSource.getClass())) {
((Property.ValueChangeNotifier) dataSource).removeListener(this);
}
// Sets the new data source
dataSource = newDataSource;
// Listens the new data source if possible
if (dataSource != null
&& Property.ValueChangeNotifier.class
.isAssignableFrom(dataSource.getClass())) {
((Property.ValueChangeNotifier) dataSource).addListener(this);
}
requestRepaint();
}
/**
* Gets the content mode of the Label.
*
* <p>
* Possible content modes include:
* <ul>
* <li><b>CONTENT_TEXT</b> Content mode, where the label contains only plain
* text. The getValue() result is coded to XML when painting.</li>
* <li><b>CONTENT_PREFORMATTED</b> Content mode, where the label contains
* preformatted text.</li>
* <li><b>CONTENT_UIDL</b> Formatted content mode, where the contents is XML
* restricted to the UIDL 1.0 formatting markups.</li>
* <li><b>CONTENT_XHTML</b> Content mode, where the label contains XHTML.
* Contents is then enclosed in DIV elements having namespace of
* "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd".</li>
* <li><b>CONTENT_XML</b> Content mode, where the label contains well-formed
* or well-balanced XML. Each of the root elements must have their default
* namespace specified.</li>
* <li><b>CONTENT_RAW</b> Content mode, where the label contains RAW output.
* Output is not required to comply to with XML. In Web Adapter output is
* inserted inside the resulting HTML document as-is. This is useful for
* some specific purposes where possibly broken HTML content needs to be
* shown, but in most cases XHTML mode should be preferred.</li>
* </ul>
* </p>
*
* @return the Content mode of the label.
*/
public int getContentMode() {
return contentMode;
}
/**
* Sets the content mode of the Label.
*
* <p>
* Possible content modes include:
* <ul>
* <li><b>CONTENT_TEXT</b> Content mode, where the label contains only plain
* text. The getValue() result is coded to XML when painting.</li>
* <li><b>CONTENT_PREFORMATTED</b> Content mode, where the label contains
* preformatted text.</li>
* <li><b>CONTENT_UIDL</b> Formatted content mode, where the contents is XML
* restricted to the UIDL 1.0 formatting markups.</li>
* <li><b>CONTENT_XHTML</b> Content mode, where the label contains XHTML.
* Contents is then enclosed in DIV elements having namespace of
* "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd".</li>
* <li><b>CONTENT_XML</b> Content mode, where the label contains well-formed
* or well-balanced XML. Each of the root elements must have their default
* namespace specified.</li>
* <li><b>CONTENT_RAW</b> Content mode, where the label contains RAW output.
* Output is not required to comply to with XML. In Web Adapter output is
* inserted inside the resulting HTML document as-is. This is useful for
* some specific purposes where possibly broken HTML content needs to be
* shown, but in most cases XHTML mode should be preferred.</li>
* </ul>
* </p>
*
* @param contentMode
* the New content mode of the label.
*/
public void setContentMode(int contentMode) {
if (contentMode != this.contentMode && contentMode >= CONTENT_TEXT
&& contentMode <= CONTENT_RAW) {
this.contentMode = contentMode;
requestRepaint();
}
}
/* Value change events */
private static final Method VALUE_CHANGE_METHOD;
static {
try {
VALUE_CHANGE_METHOD = Property.ValueChangeListener.class
.getDeclaredMethod("valueChange",
new Class[] { Property.ValueChangeEvent.class });
} catch (final java.lang.NoSuchMethodException e) {
// This should never happen
throw new java.lang.RuntimeException(
"Internal error finding methods in Label");
}
}
/**
* Value change event
*
* @author IT Mill Ltd.
* @version
* 6.3.4
* @since 3.0
*/
public class ValueChangeEvent extends Component.Event implements
Property.ValueChangeEvent {
/**
* New instance of text change event
*
* @param source
* the Source of the event.
*/
public ValueChangeEvent(Label source) {
super(source);
}
/**
* Gets the Property that has been modified.
*
* @see com.vaadin.data.Property.ValueChangeEvent#getProperty()
*/
public Property getProperty() {
return (Property) getSource();
}
}
/**
* Adds the value change listener.
*
* @param listener
* the Listener to be added.
* @see com.vaadin.data.Property.ValueChangeNotifier#addListener(com.vaadin.data.Property.ValueChangeListener)
*/
public void addListener(Property.ValueChangeListener listener) {
addListener(Label.ValueChangeEvent.class, listener, VALUE_CHANGE_METHOD);
}
/**
* Removes the value change listener.
*
* @param listener
* the Listener to be removed.
* @see com.vaadin.data.Property.ValueChangeNotifier#removeListener(com.vaadin.data.Property.ValueChangeListener)
*/
public void removeListener(Property.ValueChangeListener listener) {
removeListener(Label.ValueChangeEvent.class, listener,
VALUE_CHANGE_METHOD);
}
/**
* Emits the options change event.
*/
protected void fireValueChange() {
// Set the error message
fireEvent(new Label.ValueChangeEvent(this));
requestRepaint();
}
/**
* Listens the value change events from data source.
*
* @see com.vaadin.data.Property.ValueChangeListener#valueChange(Property.ValueChangeEvent)
*/
public void valueChange(Property.ValueChangeEvent event) {
fireValueChange();
}
/**
* Compares the Label to other objects.
*
* <p>
* Labels can be compared to other labels for sorting label contents. This
* is especially handy for sorting table columns.
* </p>
*
* <p>
* In RAW, PREFORMATTED and TEXT modes, the label contents are compared as
* is. In XML, UIDL and XHTML modes, only CDATA is compared and tags
* ignored. If the other object is not a Label, its toString() return value
* is used in comparison.
* </p>
*
* @param other
* the Other object to compare to.
* @return a negative integer, zero, or a positive integer as this object is
* less than, equal to, or greater than the specified object.
* @see java.lang.Comparable#compareTo(java.lang.Object)
*/
public int compareTo(Object other) {
String thisValue;
String otherValue;
if (contentMode == CONTENT_XML || contentMode == CONTENT_UIDL
|| contentMode == CONTENT_XHTML) {
thisValue = stripTags(toString());
} else {
thisValue = toString();
}
if (other instanceof Label
&& (((Label) other).getContentMode() == CONTENT_XML
|| ((Label) other).getContentMode() == CONTENT_UIDL || ((Label) other)
.getContentMode() == CONTENT_XHTML)) {
otherValue = stripTags(other.toString());
} else {
otherValue = other.toString();
}
return thisValue.compareTo(otherValue);
}
/**
* Strips the tags from the XML.
*
* @param xml
* the String containing a XML snippet.
* @return the original XML without tags.
*/
private String stripTags(String xml) {
final StringBuffer res = new StringBuffer();
int processed = 0;
final int xmlLen = xml.length();
while (processed < xmlLen) {
int next = xml.indexOf('<', processed);
if (next < 0) {
next = xmlLen;
}
res.append(xml.substring(processed, next));
if (processed < xmlLen) {
next = xml.indexOf('>', processed);
if (next < 0) {
next = xmlLen;
}
processed = next + 1;
}
}
return res.toString();
}
}