FoodList.java Source code

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Here is the source code for FoodList.java

Source

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

import org.eclipse.jface.viewers.ILabelProvider;
import org.eclipse.jface.viewers.ILabelProviderListener;
import org.eclipse.jface.viewers.IStructuredContentProvider;
import org.eclipse.jface.viewers.ListViewer;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.jface.viewers.ViewerFilter;
import org.eclipse.jface.window.ApplicationWindow;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;

/**
 * This class demonstrates ListViewer.
 */
public class FoodList extends ApplicationWindow {
    // The healthy filter
    private HealthyFilter filter = new HealthyFilter();

    /**
     * FoodList constructor
     */
    public FoodList() {
        super(null);
    }

    /**
     * Runs the application
     */
    public void run() {
        // Don't return from open() until window closes
        setBlockOnOpen(true);

        // Open the main window
        open();

        // Dispose the display
        Display.getCurrent().dispose();
    }

    /**
     * Configures the shell
     * 
     * @param shell
     *            the shell
     */
    protected void configureShell(Shell shell) {
        super.configureShell(shell);
        shell.setText("Food List");
    }

    /**
     * Creates the main window's contents
     * 
     * @param parent
     *            the main window
     * @return Control
     */
    protected Control createContents(Composite parent) {
        Composite composite = new Composite(parent, SWT.NONE);
        composite.setLayout(new GridLayout(1, false));

        // Add a checkbox to toggle filter
        Button filterHealthy = new Button(composite, SWT.CHECK);
        filterHealthy.setText("&Show only healthy");

        final ListViewer lv = new ListViewer(composite);
        lv.setContentProvider(new FoodContentProvider());
        lv.setLabelProvider(new FoodLabelProvider());
        lv.setInput(new GroceryList());

        // When user checks the checkbox, toggle the filter
        filterHealthy.addSelectionListener(new SelectionAdapter() {
            public void widgetSelected(SelectionEvent event) {
                if (((Button) event.widget).getSelection())
                    lv.addFilter(filter);
                else
                    lv.removeFilter(filter);
            }
        });

        parent.pack();
        return composite;
    }

    /**
     * The application entry point
     * 
     * @param args
     *            the command line arguments
     */
    public static void main(String[] args) {
        new FoodList().run();
    }
}

/**
 * This class filters only healthy items from the grocery list
 */

class HealthyFilter extends ViewerFilter {
    /**
     * Returns whether the specified element passes this filter
     * 
     * @param arg0
     *            the viewer
     * @param arg1
     *            the parent element
     * @param arg2
     *            the element
     * @return boolean
     */
    public boolean select(Viewer arg0, Object arg1, Object arg2) {
        return ((Food) arg2).isHealthy();
    }
}

/**
 * This class represents a type of food
 */

class Food {
    // The name of the food
    private String name;

    // Is it healthy?
    private boolean healthy;

    /**
     * Food constructor
     * 
     * @param name
     *            the name
     * @param healthy
     *            whether or not it's healthy
     */
    public Food(String name, boolean healthy) {
        this.name = name;
        this.healthy = healthy;
    }

    /**
     * Gets whether this is healthy
     * 
     * @return boolean
     */
    public boolean isHealthy() {
        return healthy;
    }

    /**
     * Gets the name
     * 
     * @return String
     */
    public String getName() {
        return name;
    }
}

/**
 * This class provides the labels for the FoodList application
 */

class FoodLabelProvider implements ILabelProvider {

    /**
     * ListViewers don't support images
     * 
     * @param arg0
     *            the element
     * @return Image
     */
    public Image getImage(Object arg0) {
        return null;
    }

    /**
     * Gets the text for an element
     * 
     * @param arg0
     *            the element
     * @return String
     */
    public String getText(Object arg0) {
        return ((Food) arg0).getName();
    }

    /**
     * Adds a listener
     * 
     * @param arg0
     *            the listener
     */
    public void addListener(ILabelProviderListener arg0) {
        // Throw it away
    }

    /**
     * Disposes any resources
     */
    public void dispose() {
        // Nothing to dispose
    }

    /**
     * Returns whether changing the specified property for the specified element
     * affect the label
     * 
     * @param arg0
     *            the element
     * @param arg1
     *            the property
     * @return boolean
     */
    public boolean isLabelProperty(Object arg0, String arg1) {
        return false;
    }

    /**
     * Removes a listener
     * 
     * @param arg0
     *            the listener
     */
    public void removeListener(ILabelProviderListener arg0) {
        // Ignore
    }
}

/**
 * This class contains all the foods on the "grocery list"
 */

class GroceryList {
    // Holds the foods
    private List foods;

    /**
     * Constructs a grocery list
     */
    public GroceryList() {
        foods = new ArrayList();

        // Add some foods
        foods.add(new Food("Broccoli", true));
        foods.add(new Food("Bundt Cake", false));
        foods.add(new Food("Cabbage", true));
        foods.add(new Food("Candy Canes", false));
        foods.add(new Food("Eggs", true));
        foods.add(new Food("Potato Chips", false));
        foods.add(new Food("Milk", true));
        foods.add(new Food("Soda", false));
        foods.add(new Food("Chicken", true));
        foods.add(new Food("Cinnamon Rolls", false));
    }

    /**
     * Returns the foods in this grocery list
     * 
     * @return List
     */
    public List getFoods() {
        return Collections.unmodifiableList(foods);
    }
}

/**
 * This class provides the content for the FoodList application
 */

class FoodContentProvider implements IStructuredContentProvider {
    /**
     * Gets the food items for the list
     * 
     * @param arg0
     *            the data model
     * @return Object[]
     */
    public Object[] getElements(Object arg0) {
        return ((GroceryList) arg0).getFoods().toArray();
    }

    /**
     * Disposes any created resources
     */
    public void dispose() {
        // Do nothing
    }

    /**
     * Called when the input changes
     * 
     * @param arg0
     *            the viewer
     * @param arg1
     *            the old input
     * @param arg2
     *            the new input
     */
    public void inputChanged(Viewer arg0, Object arg1, Object arg2) {
        // Do nothing
    }
}