org.eclipse.jface.snippets.viewers.Snippet005TreeCustomMenu.java Source code

Introduction

Here is the source code for org.eclipse.jface.snippets.viewers.Snippet005TreeCustomMenu.java

Source

/*******************************************************************************
 * Copyright (c) 2006 - 2015 Tom Schindl and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     Tom Schindl <tom.schindl@bestsolution.at> - initial API and implementation
 *     Lars Vogel <Lars.Vogel@vogella.com> - Bug 414565, 442278, 475361
 *******************************************************************************/

package org.eclipse.jface.snippets.viewers;

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

import org.eclipse.jface.action.Action;
import org.eclipse.jface.action.IMenuListener;
import org.eclipse.jface.action.IMenuManager;
import org.eclipse.jface.action.MenuManager;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.ITreeContentProvider;
import org.eclipse.jface.viewers.LabelProvider;
import org.eclipse.jface.viewers.TreeViewer;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.swt.SWT;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Tree;
import org.eclipse.swt.widgets.TreeColumn;

/**
 * Customized context menu based on TreeItem-Selection
 *
 */
public class Snippet005TreeCustomMenu {
    private class MyContentProvider implements ITreeContentProvider {

        @Override
        public Object[] getElements(Object inputElement) {
            return ((MyModel) inputElement).child.toArray();
        }

        @Override
        public void dispose() {

        }

        @Override
        public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {

        }

        @Override
        public Object[] getChildren(Object parentElement) {
            return getElements(parentElement);
        }

        @Override
        public Object getParent(Object element) {
            if (element == null) {
                return null;
            }

            return ((MyModel) element).parent;
        }

        @Override
        public boolean hasChildren(Object element) {
            return ((MyModel) element).child.size() > 0;
        }

    }

    public class MyModel {
        public MyModel parent;

        public List<MyModel> child = new ArrayList<>();

        public int counter;

        public MyModel(int counter, MyModel parent) {
            this.parent = parent;
            this.counter = counter;
        }

        @Override
        public String toString() {
            String rv = "Item ";
            if (parent != null) {
                rv = parent + ".";
            }

            rv += counter;

            return rv;
        }
    }

    public Snippet005TreeCustomMenu(Shell shell) {
        final TreeViewer v = new TreeViewer(shell);
        v.setLabelProvider(new LabelProvider());
        v.setContentProvider(new MyContentProvider());
        v.setInput(createModel());
        createColumn(v.getTree(), "Values");

        final Action a = new Action("") {
        };
        final MenuManager mgr = new MenuManager();
        mgr.setRemoveAllWhenShown(true);

        mgr.addMenuListener(new IMenuListener() {

            @Override
            public void menuAboutToShow(IMenuManager manager) {
                IStructuredSelection selection = v.getStructuredSelection();
                if (!selection.isEmpty()) {
                    a.setText("Action for " + selection.getFirstElement());
                    mgr.add(a);
                }
            }
        });
        v.getControl().setMenu(mgr.createContextMenu(v.getControl()));
    }

    public void createColumn(Tree tr, String text) {
        TreeColumn column = new TreeColumn(tr, SWT.NONE);
        column.setWidth(100);
        column.setText(text);
        tr.setHeaderVisible(true);
    }

    private MyModel createModel() {

        MyModel root = new MyModel(0, null);
        root.counter = 0;

        MyModel tmp;
        for (int i = 1; i < 10; i++) {
            tmp = new MyModel(i, root);
            root.child.add(tmp);
            for (int j = 1; j < i; j++) {
                tmp.child.add(new MyModel(j, tmp));
            }
        }

        return root;
    }

    public static void main(String[] args) {
        Display display = new Display();
        Shell shell = new Shell(display);
        shell.setLayout(new FillLayout());
        new Snippet005TreeCustomMenu(shell);
        shell.open();

        while (!shell.isDisposed()) {
            if (!display.readAndDispatch())
                display.sleep();
        }

        display.dispose();
    }
}