org.eclipse.jface.snippets.viewers.Snippet022TableViewerRefreshNoScroll.java Source code

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Here is the source code for org.eclipse.jface.snippets.viewers.Snippet022TableViewerRefreshNoScroll.java

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/*******************************************************************************
 * 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 - initial API and implementation
 *     Jeanderson Candido <http://jeandersonbc.github.io> - Bug 414565
 *     Lars Vogel <Lars.Vogel@vogella.com> - Bug 442278, 475361
 *******************************************************************************/

package org.eclipse.jface.snippets.viewers;

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

import org.eclipse.jface.viewers.ArrayContentProvider;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.LabelProvider;
import org.eclipse.jface.viewers.StructuredViewer;
import org.eclipse.jface.viewers.TableViewer;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.TableColumn;
import org.eclipse.swt.widgets.TableItem;

/**
 * A simple TableViewer to demonstrating how viewers could be refresh and
 * scrolling avoided in 3.2. In 3.3 implementors should consider using the
 * {@link StructuredViewer#refresh(Object, boolean)} instead.
 *
 */
public class Snippet022TableViewerRefreshNoScroll {

    public class MyModel {
        public int counter;

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

        @Override
        public String toString() {
            return "Item " + this.counter;
        }
    }

    public Snippet022TableViewerRefreshNoScroll(Shell shell) {
        shell.setLayout(new GridLayout(2, false));
        final TableViewer v = new TableViewer(shell, SWT.BORDER | SWT.FULL_SELECTION);

        TableColumn column = new TableColumn(v.getTable(), SWT.NONE);
        column.setWidth(200);
        column.setText("Column 0");

        v.setLabelProvider(new LabelProvider());
        v.setContentProvider(ArrayContentProvider.getInstance());
        v.setInput(createModel(100));
        v.getTable().setLinesVisible(true);
        v.getTable().setHeaderVisible(true);
        v.getTable().setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true, 2, 1));

        Button b = new Button(shell, SWT.PUSH);
        b.setText("Refresh with Scrolling");
        b.addSelectionListener(new SelectionAdapter() {

            @Override
            public void widgetSelected(SelectionEvent e) {
                v.refresh();
            }

        });

        b = new Button(shell, SWT.PUSH);
        b.setText("Refresh with NO-Scrolling");
        b.addSelectionListener(new SelectionAdapter() {

            @Override
            public void widgetSelected(SelectionEvent e) {
                v.getTable().setTopIndex(0);
                IStructuredSelection selection = v.getStructuredSelection();
                v.getTable().deselectAll();
                v.refresh();
                if (!selection.isEmpty()) {
                    int[] indices = new int[selection.size()];

                    Iterator<?> it = selection.iterator();
                    TableItem[] items = v.getTable().getItems();
                    Object modelElement;

                    int counter = 0;
                    while (it.hasNext()) {
                        modelElement = it.next();
                        for (int i = 0; i < items.length; i++) {
                            if (items[i].getData() == modelElement) {
                                indices[counter++] = i;
                            }
                        }
                    }

                    if (counter < indices.length) {
                        System.arraycopy(items, 0, indices = new int[counter], 0, counter);
                    }

                    v.getTable().select(indices);
                }
            }

        });
    }

    private List<MyModel> createModel(int size) {
        List<MyModel> elements = new ArrayList<>();

        for (int i = 0; i < size; i++) {
            elements.add(new MyModel(i));
        }
        return elements;
    }

    /**
     * @param args
     */
    public static void main(String[] args) {
        Display display = new Display();
        Shell shell = new Shell(display);
        new Snippet022TableViewerRefreshNoScroll(shell);
        shell.open();

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

}