Cloudio
Note to non-wiki readers: This documentation is generated from the Eclipse wiki - if you have corrections or additions it would be awesome if you added them in the original wiki page.
The Cloudio component provides support for visualizing tag clouds within a dedicated SWT Canvas or JFace viewer. It is internally decomposed into the single Cloudio.UI module. There are also a couple of undeployed Cloudio UI Examples that demonstrate usage of the (still internal) API. The user documentation is provided in terms of the Cloudio User Guide.
- feature: org.eclipse.gef.cloudio.ui
- bundle: org.eclipse.gef.cloudio.ui
The Cloudio.UI module of Cloudio realizes the Tag cloud view end-user features, as outlined in the Cloudio User Guide. It does not provide any public API yet, but exposes its internal API (guarded by an x-friends directive).
- feature: org.eclipse.gef.cloudio.ui
- bundle: org.eclipse.gef.cloudio.ui
The Cloudio.UI module of Cloudio provides SWT- and JFace-based support for rendering tag clouds.
- package: org.eclipse.gef.cloudio.internal.ui
The {Root} package provides an SWT widget (TagCloud) and a JFace viewer (TagCloudViewer), which support rendering of word clouds.
A TagCloud is a special org.eclipse.swt.widgets.Canvas, dedicated to display a tag cloud. It expects the to be rendered words and related properties (weight, angle, color, font) to be represented as Word input elements and can be created as follows:
public static void main(String [] args) {
final Display display = new Display();
final Shell shell = new Shell(display);
TagCloud cloud = new TagCloud(shell, SWT.NONE);
// Generate some dummy words - color, weight and fontdata must
// always be defined.
List<Word> words = new ArrayList<Word>();
Word w = new Word("Hello");
w.setColor(display.getSystemColor(SWT.COLOR_DARK_CYAN));
w.weight = 1;
w.setFontData(cloud.getFont().getFontData().clone());
words.add(w);
w = new Word("Cloudio");
w.setColor(display.getSystemColor(SWT.COLOR_DARK_GREEN));
w.setFontData(cloud.getFont().getFontData().clone());
w.weight = 0.5;
w.angle = -45;
words.add(w);
shell.setBounds(50,50, 300, 300);
cloud.setBounds(0,0, shell.getBounds().width, shell.getBounds().height);
// Assign the list of words to the cloud:
cloud.setWords(words, null);
shell.open();
while (!shell.isDisposed()) {
if (!display.readAndDispatch()) display.sleep();
}
display.dispose();
}The result should look similar to this (String positions are assigned by random):
A TagCloudViewer is a special org.eclipse.jface.viewers.ContentViewer, that renders a tag cloud. It is internally based on a TagCloud and enhances the functionality of the tag cloud: it is possible to select and deselect elements by mouse click, to zoom in or out using the mouse wheel and to display tool tips on words. The TagCloudViewer expects an org.eclipse.jface.viewers.IStructuredContentProvider and an ICloudLabelProvider. The words that are to be rendered in the TagCloud are inferred by queuing the ICloudLabelProvider for labels of the elements returned by the org.eclipse.jface.viewers.IStructuredContentProvider. The properties of the words (weight, color, font, angle) are retrieved via the ICloudLabelProvider for each word as well.
A TagCloudViewer can be used as follows:
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import org.eclipse.jface.viewers.BaseLabelProvider;
import org.eclipse.jface.viewers.ISelectionChangedListener;
import org.eclipse.jface.viewers.IStructuredContentProvider;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.SelectionChangedEvent;
import org.eclipse.jface.viewers.StructuredSelection;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.FontData;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.zest.cloudio.ICloudLabelProvider;
import org.eclipse.zest.cloudio.TagCloud;
import org.eclipse.zest.cloudio.TagCloudViewer;
public class TagCloudViewerSnippet {
static class CustomLabelProvider extends BaseLabelProvider implements ICloudLabelProvider {
private Font font;
public CustomLabelProvider(Font font) {
this.font = font;
}
@Override
public String getLabel(Object element) {
return element.toString();
}
@Override
public double getWeight(Object element) {
return Math.random();
}
@Override
public Color getColor(Object element) {
return Display.getDefault().getSystemColor(SWT.COLOR_GREEN);
}
@Override
public FontData[] getFontData(Object element) {
return font.getFontData();
}
@Override
public float getAngle(Object element) {
return (float) (-90 + Math.random() * 180);
}
@Override
public String getToolTip(Object element) {
return element.toString();
}
}
public static void main(String [] args) {
final Display display = new Display();
final Shell shell = new Shell(display);
TagCloud cloud = new TagCloud(shell, SWT.NONE);
final TagCloudViewer viewer = new TagCloudViewer(cloud);
// A simple content provider for a list of elements
viewer.setContentProvider(new IStructuredContentProvider() {
@Override
public void dispose() { }
@Override
public void inputChanged(Viewer viewer, Object oldInput,
Object newInput) {}
@Override
public Object[] getElements(Object inputElement) {
return ((List<?>)inputElement).toArray();
}
});
// A simple label provider (see above)
viewer.setLabelProvider(new CustomLabelProvider(cloud.getFont()));
// Demo of an selection listener
viewer.addSelectionChangedListener(new ISelectionChangedListener() {
@Override
public void selectionChanged(SelectionChangedEvent event) {
IStructuredSelection selection = (IStructuredSelection) viewer.getSelection();
System.out.println("Selection: " + selection);
}
});
// Demo data
List<String> data = new ArrayList<String>();
data.add("Hello");
data.add("World");
data.add("Hello Cloudio");
shell.setBounds(50,50, 300, 300);
cloud.setBounds(0,0, shell.getBounds().width, shell.getBounds().height);
// Set the input of the viewer
viewer.setInput(data);
// Set initial selection:
viewer.setSelection(new StructuredSelection(Arrays.asList("Hello Cloudio")));
shell.open();
while (!shell.isDisposed()) {
if (!display.readAndDispatch()) display.sleep();
}
display.dispose();
}
}The result will look similar to this:
- package: org.eclipse.gef.cloudio.internal.ui.layout
The Layout package provides the contract (ILayouter) for algorithms that perform placement of words during tag cloud generation, as well as a related default implementation (DefaultLayouter).
An ILayouter is used by a TagCloud to compute the actual placement of words inside a given area. The DefaultLayouter places words similar to the algorithm used by Wordle.
- package: org.eclipse.gef.cloudio.internal.ui.util
The Util package provides a two-dimensional tree structure to store non-overlapping rectangles (RectTree), a custom rectangle implementation (SmallRect) with short precision used by it (which will probably be replaced with org.eclipse.gef.geometry.planar.Rectangle in the future), and a CloudMatrix, which represents a drawable area within a tag cloud through a RectTree.
A RectTree is a two-dimensional tree structure to store non-overlapping rectangles that are represented through RectNodes, which are internally based on a short-precision rectangle representation (SmallRect).
A CloudMatrix represents the drawable area within a tag cloud (and information about which word is placed at which coordinate), internally based on a RectTree.