swt.snippets.AlternateColumnColorExample.java Source code

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Here is the source code for swt.snippets.AlternateColumnColorExample.java

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/*
 * Copyright by AGYNAMIX(R). All rights reserved. 
 * This file is made available under the terms of the
 * license this product is released under.
 * 
 * For details please see the license file you should have
 * received, or go to:
 * 
 * http://www.agynamix.com
 * 
 * Contributors: agynamix.com (http://www.agynamix.com)
 */
package swt.snippets;

import org.eclipse.jface.viewers.ColumnLabelProvider;
import org.eclipse.jface.viewers.IStructuredContentProvider;
import org.eclipse.jface.viewers.TableViewer;
import org.eclipse.jface.viewers.TableViewerColumn;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.jface.viewers.ViewerCell;
import org.eclipse.jface.viewers.ViewerFilter;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.TableItem;

public class AlternateColumnColorExample {

    private class MyContentProvider implements IStructuredContentProvider {

        /*
         * (non-Javadoc)
         * 
         * @see org.eclipse.jface.viewers.IStructuredContentProvider#getElements(java.lang.Object)
         */
        public Object[] getElements(Object inputElement) {
            return (MyModel[]) inputElement;
        }

        /*
         * (non-Javadoc)
         * 
         * @see org.eclipse.jface.viewers.IContentProvider#dispose()
         */
        public void dispose() {

        }

        /*
         * (non-Javadoc)
         * 
         * @see org.eclipse.jface.viewers.IContentProvider#inputChanged(org.eclipse.jface.viewers.Viewer, java.lang.Object,
         * java.lang.Object)
         */
        public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
        }

    }

    public class MyModel {
        public int counter;

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

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

    private class OptimizedIndexSearcher {
        private int lastIndex = 0;

        public boolean isEven(TableItem item) {
            TableItem[] items = item.getParent().getItems();

            // 1. Search the next ten items
            for (int i = lastIndex; i < items.length && lastIndex + 10 > i; i++) {
                if (items[i] == item) {
                    lastIndex = i;
                    return lastIndex % 2 == 0;
                }
            }

            // 2. Search the previous ten items
            for (int i = lastIndex; i < items.length && lastIndex - 10 > i; i--) {
                if (items[i] == item) {
                    lastIndex = i;
                    return lastIndex % 2 == 0;
                }
            }

            // 3. Start from the beginning
            for (int i = 0; i < items.length; i++) {
                if (items[i] == item) {
                    lastIndex = i;
                    return lastIndex % 2 == 0;
                }
            }

            return false;
        }
    }

    public AlternateColumnColorExample(Shell shell) {
        final TableViewer v = new TableViewer(shell, SWT.BORDER | SWT.FULL_SELECTION | SWT.VIRTUAL);
        v.setContentProvider(new MyContentProvider());

        final OptimizedIndexSearcher searcher = new OptimizedIndexSearcher();

        TableViewerColumn column = new TableViewerColumn(v, SWT.NONE);
        column.getColumn().setWidth(200);
        column.getColumn().setText("Column 1");
        column.setLabelProvider(new ColumnLabelProvider() {
            boolean even = true;

            public Color getBackground(Object element) {
                if (even) {
                    return null;
                } else {
                    return v.getTable().getDisplay().getSystemColor(SWT.COLOR_GRAY);
                }
            }

            public void update(ViewerCell cell) {
                even = searcher.isEven((TableItem) cell.getItem());
                super.update(cell);
            }
        });

        column = new TableViewerColumn(v, SWT.NONE);
        column.getColumn().setWidth(200);
        column.getColumn().setText("Column 2");
        column.setLabelProvider(new ColumnLabelProvider() {
            boolean even = true;

            public Color getBackground(Object element) {
                if (even) {
                    return null;
                } else {
                    return v.getTable().getDisplay().getSystemColor(SWT.COLOR_GRAY);
                }
            }

            public void update(ViewerCell cell) {
                even = searcher.isEven((TableItem) cell.getItem());
                super.update(cell);
            }

        });

        MyModel[] model = createModel();
        v.setInput(model);
        v.getTable().setLinesVisible(true);
        v.getTable().setHeaderVisible(true);

        final ViewerFilter filter = new ViewerFilter() {

            public boolean select(Viewer viewer, Object parentElement, Object element) {
                return ((MyModel) element).counter % 2 == 0;
            }

        };

        Button b = new Button(shell, SWT.PUSH);
        b.addSelectionListener(new SelectionAdapter() {
            boolean b = true;

            public void widgetSelected(SelectionEvent e) {
                if (b) {
                    v.setFilters(new ViewerFilter[] { filter });
                    b = false;
                } else {
                    v.setFilters(new ViewerFilter[0]);
                    b = true;
                }
            }

        });
    }

    private MyModel[] createModel() {
        MyModel[] elements = new MyModel[100000];

        for (int i = 0; i < 100000; i++) {
            elements[i] = new MyModel(i);
        }

        return elements;
    }

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

        Shell shell = new Shell(display);
        shell.setLayout(new FillLayout());
        new AlternateColumnColorExample(shell);
        shell.open();

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

        display.dispose();

    }

}