Zest and JFace Example

5.1. Create Project

Create a new RCP application "sawan.modi.zest.jface". Use the " RCP application with a view" as a template. Add the zest dependencies to your MANIFEST.MF. Change the Perspective.java to the following (we don't want a standalone view).

    
package sawan.modi.zest.jface;

import org.eclipse.ui.IPageLayout;
import org.eclipse.ui.IPerspectiveFactory;

public class Perspective implements IPerspectiveFactory {

 public void createInitialLayout(IPageLayout layout) {
  String editorArea = layout.getEditorArea();
  layout.setEditorAreaVisible(false);
  layout.setFixed(true);
  
  layout.addView(View.ID, IPageLayout.LEFT, 1.0f, editorArea);
 }

}

   

5.2. Model

Create the following model. Please note that the model can be anything as long as you can logically convert it into a connected Graph.

    
package sawan.modi.zest.jface.model;

import java.util.ArrayList;
import java.util.List;

public class MyNode {
 private final String id;
 private final String name;
 private List connections;

 public MyNode(String id, String name) {
  this.id = id;
  this.name = name;
  this.connections = new ArrayList();
 }

 public String getId() {
  return id;
 }

 public String getName() {
  return name;
 }

 public List getConnectedTo() {
  return connections;
 }

}

   

    
package sawan.modi.zest.jface.model;

public class MyConnection {
 final String id;
 final String label;
 final MyNode source;
 final MyNode destination;
 
 public MyConnection(String id, String label, MyNode source, MyNode destination) {
  this.id = id;
  this.label = label;
  this.source = source;
  this.destination = destination;
 }

 public String getLabel() {
  return label;
 }
 
 public MyNode getSource() {
  return source;
 }
 public MyNode getDestination() {
  return destination;
 }
 
}


   

Also build this class which provides an instance of the data model.

    
package sawan.modi.zest.jface.model;

import java.util.ArrayList;
import java.util.List;

public class NodeModelContentProvider {
 private List connections;
 private List nodes;

 public NodeModelContentProvider() {
  // Image here a fancy DB access
  // Now create a few nodes
  nodes = new ArrayList();
  MyNode node = new MyNode("1", "Hamburg");
  nodes.add(node);
  node = new MyNode("2", "Frankfurt");
  nodes.add(node);
  node = new MyNode("3", "Berlin");
  nodes.add(node);
  node = new MyNode("4", "Munich");
  nodes.add(node);
  node = new MyNode("5", "Eppelheim");
  nodes.add(node);
  node = new MyNode("6", "Ahrensboek");
  nodes.add(node);

  connections = new ArrayList();
  MyConnection connect = new MyConnection("1", "1", nodes.get(0),
    nodes.get(1));
  connections.add(connect);
  connect = new MyConnection("2", "2", nodes.get(0), nodes.get(4));
  connections.add(connect);
  connect = new MyConnection("3", "3", nodes.get(2), nodes.get(1));
  connections.add(connect);
  connect = new MyConnection("4", "3", nodes.get(1), nodes.get(3));
  connections.add(connect);

  // Because we are lasy we save the info about the connections in the
  // nodes

  for (MyConnection connection : connections) {
   connection.getSource().getConnectedTo()
     .add(connection.getDestination());
  }
 }

 public List getNodes() {
  return nodes;
 }
}

   

5.3. Providers

Create the following content and label providers.

    
package sawan.modi.zest.jface.zestviewer;

import org.eclipse.jface.viewers.ArrayContentProvider;
import org.eclipse.zest.core.viewers.IGraphEntityContentProvider;

import sawan.modi.zest.jface.model.MyNode;

public class ZestNodeContentProvider extends ArrayContentProvider  implements IGraphEntityContentProvider {

 @Override
 public Object[] getConnectedTo(Object entity) {
  if (entity instanceof MyNode) {
   MyNode node = (MyNode) entity;
   return node.getConnectedTo().toArray();
  }
  throw new RuntimeException("Type not supported");
 }
}

   

    
package sawan.modi.zest.jface.zestviewer;

import org.eclipse.jface.viewers.LabelProvider;
import org.eclipse.zest.core.viewers.EntityConnectionData;

import sawan.modi.zest.jface.model.MyConnection;
import sawan.modi.zest.jface.model.MyNode;

public class ZestLabelProvider extends LabelProvider {
 @Override
 public String getText(Object element) {
  if (element instanceof MyNode){
   MyNode myNode = (MyNode) element;
   return myNode.getName();
  }
  if (element instanceof MyConnection){
   MyConnection myConnection = (MyConnection) element;
   return myConnection.getLabel();
  }
  
  if (element instanceof EntityConnectionData){
   return "";
  }
  throw new RuntimeException("Wrong type: " + element.getClass().toString() );
 }
}

   

5.4. View

Change the view to the following.

    
package sawan.modi.zest.jface;

import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.ui.IActionBars;
import org.eclipse.ui.part.ViewPart;
import org.eclipse.zest.core.viewers.AbstractZoomableViewer;
import org.eclipse.zest.core.viewers.GraphViewer;
import org.eclipse.zest.core.viewers.IZoomableWorkbenchPart;
import org.eclipse.zest.core.viewers.ZoomContributionViewItem;
import org.eclipse.zest.layouts.LayoutAlgorithm;
import org.eclipse.zest.layouts.LayoutStyles;
import org.eclipse.zest.layouts.algorithms.TreeLayoutAlgorithm;

import sawan.modi.zest.jface.model.NodeModelContentProvider;
import sawan.modi.zest.jface.zestviewer.ZestLabelProvider;
import sawan.modi.zest.jface.zestviewer.ZestNodeContentProvider;

public class View extends ViewPart implements IZoomableWorkbenchPart {
 public static final String ID = "sawan.modi.zest.jface.view";
 private GraphViewer viewer;

 public void createPartControl(Composite parent) {
  viewer = new GraphViewer(parent, SWT.BORDER);
  viewer.setContentProvider(new ZestNodeContentProvider());
  viewer.setLabelProvider(new ZestLabelProvider());
  NodeModelContentProvider model = new NodeModelContentProvider();
  viewer.setInput(model.getNodes());
  LayoutAlgorithm layout = setLayout();
  viewer.setLayoutAlgorithm(layout, true);
  viewer.applyLayout();
  fillToolBar();
 }

 private LayoutAlgorithm setLayout() {
  LayoutAlgorithm layout;
  // layout = new
  // SpringLayoutAlgorithm(LayoutStyles.NO_LAYOUT_NODE_RESIZING);
  layout = new TreeLayoutAlgorithm(LayoutStyles.NO_LAYOUT_NODE_RESIZING);
  // layout = new
  // GridLayoutAlgorithm(LayoutStyles.NO_LAYOUT_NODE_RESIZING);
  // layout = new
  // HorizontalTreeLayoutAlgorithm(LayoutStyles.NO_LAYOUT_NODE_RESIZING);
  // layout = new
  // RadialLayoutAlgorithm(LayoutStyles.NO_LAYOUT_NODE_RESIZING);
  return layout;

 }

 /**
  * Passing the focus request to the viewer's control.
  */
 public void setFocus() {
 }

 private void fillToolBar() {
  ZoomContributionViewItem toolbarZoomContributionViewItem = new ZoomContributionViewItem(
    this);
  IActionBars bars = getViewSite().getActionBars();
  bars.getMenuManager().add(toolbarZoomContributionViewItem);

 }

 @Override
 public AbstractZoomableViewer getZoomableViewer() {
  return viewer;
 }
}

   

The result should look like the following.

5.5. Filter

You can define a filter on the viewer via setFilters();

For example define the following filter.

    
package sawan.modi.zest.jface.zestviewer;

import org.eclipse.jface.viewers.Viewer;
import org.eclipse.jface.viewers.ViewerFilter;

import sawan.modi.zest.jface.model.MyNode;

public class NodeFilter extends ViewerFilter {

 @Override
 public boolean select(Viewer viewer, Object parentElement, Object element) {
  
  if (element instanceof MyNode) {
   MyNode node = (MyNode) element;
   return node.getName().toLowerCase().contains("a");
   
  }
  return true;
 }

}

   

Apply the filter to the view to filter all elements.

    
package sawan.modi.zest.jface;

import org.eclipse.jface.viewers.ViewerFilter;
import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.ui.IActionBars;
import org.eclipse.ui.part.ViewPart;
import org.eclipse.zest.core.viewers.AbstractZoomableViewer;
import org.eclipse.zest.core.viewers.GraphViewer;
import org.eclipse.zest.core.viewers.IZoomableWorkbenchPart;
import org.eclipse.zest.core.viewers.ZoomContributionViewItem;
import org.eclipse.zest.layouts.LayoutAlgorithm;
import org.eclipse.zest.layouts.LayoutStyles;
import org.eclipse.zest.layouts.algorithms.TreeLayoutAlgorithm;

import sawan.modi.zest.jface.model.NodeModelContentProvider;
import sawan.modi.zest.jface.zestviewer.NodeFilter;
import sawan.modi.zest.jface.zestviewer.ZestLabelProvider;
import sawan.modi.zest.jface.zestviewer.ZestNodeContentProvider;

public class View extends ViewPart implements IZoomableWorkbenchPart {
 public static final String ID = "sawan.modi.zest.jface.view";
 private GraphViewer viewer;

 public void createPartControl(Composite parent) {
  viewer = new GraphViewer(parent, SWT.BORDER);
  viewer.setContentProvider(new ZestNodeContentProvider());
  viewer.setLabelProvider(new ZestLabelProvider());
  NodeModelContentProvider model = new NodeModelContentProvider();
  viewer.setInput(model.getNodes());
  LayoutAlgorithm layout = setLayout();
  viewer.setLayoutAlgorithm(layout, true);
  viewer.applyLayout();
  NodeFilter filter = new NodeFilter();
  ViewerFilter[] filters = new ViewerFilter[1];
  filters[0]= filter;
  viewer.setFilters(filters);
  fillToolBar();
 }

 private LayoutAlgorithm setLayout(){
  LayoutAlgorithm layout;
//  layout = new SpringLayoutAlgorithm(LayoutStyles.NO_LAYOUT_NODE_RESIZING); 
  layout = new TreeLayoutAlgorithm(LayoutStyles.NO_LAYOUT_NODE_RESIZING);
//  layout = new GridLayoutAlgorithm(LayoutStyles.NO_LAYOUT_NODE_RESIZING);
//  layout = new HorizontalTreeLayoutAlgorithm(LayoutStyles.NO_LAYOUT_NODE_RESIZING);
//  layout = new RadialLayoutAlgorithm(LayoutStyles.NO_LAYOUT_NODE_RESIZING);
  return layout;
  
 }

 /**
  * Passing the focus request to the viewer's control.
  */
 public void setFocus() {
 }
 
 private void fillToolBar() {
  ZoomContributionViewItem toolbarZoomContributionViewItem = new ZoomContributionViewItem(this);
  IActionBars bars = getViewSite().getActionBars();
  bars.getMenuManager().add(toolbarZoomContributionViewItem);

 }

 @Override
 public AbstractZoomableViewer getZoomableViewer() {
  return viewer;
 }
}

   

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