org.eclipse.swt.examples.graphics.LineStyleTab.java Source code

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Here is the source code for org.eclipse.swt.examples.graphics.LineStyleTab.java

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/*******************************************************************************
 * Copyright (c) 2006, 2016 IBM Corporation 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:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/

package org.eclipse.swt.examples.graphics;

import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Device;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Pattern;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Menu;
import org.eclipse.swt.widgets.Spinner;

/**
 * This tab demonstrates line styles applicable to a line.  It shows the use of the
 * <code>GC.setLineStyle()</code> method.
 */
public class LineStyleTab extends GraphicsTab {

    Button colorButton;
    GraphicsBackground lineColor;
    Menu menu;
    Spinner lineWidthSpinner;

    public LineStyleTab(GraphicsExample example) {
        super(example);
    }

    @Override
    public String getCategory() {
        return GraphicsExample.getResourceString("Lines"); //$NON-NLS-1$
    }

    @Override
    public String getText() {
        return GraphicsExample.getResourceString("LineStyles"); //$NON-NLS-1$
    }

    @Override
    public String getDescription() {
        return GraphicsExample.getResourceString("LineStylesDescription"); //$NON-NLS-1$
    }

    @Override
    public void dispose() {
        if (menu != null) {
            menu.dispose();
            menu = null;
        }
    }

    @Override
    public void createControlPanel(Composite parent) {

        Composite comp;

        comp = new Composite(parent, SWT.NONE);
        comp.setLayout(new GridLayout(2, false));

        new Label(comp, SWT.CENTER).setText(GraphicsExample.getResourceString("LineWidth")); //$NON-NLS-1$
        lineWidthSpinner = new Spinner(comp, SWT.BORDER | SWT.WRAP);
        lineWidthSpinner.setSelection(10);
        lineWidthSpinner.setMinimum(1);
        lineWidthSpinner.setMaximum(30);
        lineWidthSpinner.addListener(SWT.Selection, event -> example.redraw());

        ColorMenu cm = new ColorMenu();
        cm.setPatternItems(example.checkAdvancedGraphics());
        menu = cm.createMenu(parent.getParent(), gb -> {
            lineColor = gb;
            colorButton.setImage(gb.getThumbNail());
            example.redraw();
        });

        // create color button
        comp = new Composite(parent, SWT.NONE);
        comp.setLayout(new GridLayout());

        // initialize the foreground to the 5th item in the menu (blue)
        lineColor = (GraphicsBackground) menu.getItem(4).getData();

        // color button
        colorButton = new Button(comp, SWT.PUSH);
        colorButton.setText(GraphicsExample.getResourceString("Color")); //$NON-NLS-1$
        colorButton.setImage(lineColor.getThumbNail());
        colorButton.addListener(SWT.Selection, event -> {
            final Button button = (Button) event.widget;
            final Composite parent1 = button.getParent();
            Rectangle bounds = button.getBounds();
            Point point = parent1.toDisplay(new Point(bounds.x, bounds.y));
            menu.setLocation(point.x, point.y + bounds.height);
            menu.setVisible(true);
        });
    }

    @Override
    public void paint(GC gc, int width, int height) {
        Device device = gc.getDevice();

        Pattern pattern = null;
        if (lineColor.getBgColor1() != null) {
            gc.setForeground(lineColor.getBgColor1());
        } else if (lineColor.getBgImage() != null) {
            pattern = new Pattern(device, lineColor.getBgImage());
            gc.setForegroundPattern(pattern);
        }

        // set line width
        gc.setLineWidth(lineWidthSpinner.getSelection());

        // draw lines with caps
        gc.drawLine(3 * width / 16, 1 * height / 6, 13 * width / 16, 1 * height / 6);
        gc.setLineStyle(SWT.LINE_DASH);
        gc.drawLine(3 * width / 16, 2 * height / 6, 13 * width / 16, 2 * height / 6);
        gc.setLineStyle(SWT.LINE_DOT);
        gc.drawLine(3 * width / 16, 3 * height / 6, 13 * width / 16, 3 * height / 6);
        gc.setLineStyle(SWT.LINE_DASHDOT);
        gc.drawLine(3 * width / 16, 4 * height / 6, 13 * width / 16, 4 * height / 6);
        gc.setLineStyle(SWT.LINE_DASHDOTDOT);
        gc.drawLine(3 * width / 16, 5 * height / 6, 13 * width / 16, 5 * height / 6);

        // draw labels
        Font font = new Font(device, getPlatformFont(), 20, SWT.NORMAL);
        gc.setFont(font);

        gc.setForeground(device.getSystemColor(SWT.COLOR_BLACK));

        String text = GraphicsExample.getResourceString("Solid"); //$NON-NLS-1$
        Point size = gc.stringExtent(text);
        gc.drawString(text, (width - size.x) / 2, 1 * height / 12, true);
        text = GraphicsExample.getResourceString("Dash"); //$NON-NLS-1$
        size = gc.stringExtent(text);
        gc.drawString(text, (width - size.x) / 2, 3 * height / 12, true);
        text = GraphicsExample.getResourceString("Dot"); //$NON-NLS-1$
        size = gc.stringExtent(text);
        gc.drawString(text, (width - size.x) / 2, 5 * height / 12, true);
        text = GraphicsExample.getResourceString("DashDot"); //$NON-NLS-1$
        size = gc.stringExtent(text);
        gc.drawString(text, (width - size.x) / 2, 7 * height / 12, true);
        text = GraphicsExample.getResourceString("DashDotDot"); //$NON-NLS-1$
        size = gc.stringExtent(text);
        gc.drawString(text, (width - size.x) / 2, 9 * height / 12, true);
        font.dispose();
    }

    /**
     * Returns the name of a valid font for the resident platform.
     */
    static String getPlatformFont() {
        if (SWT.getPlatform() == "win32") {
            return "Arial";
        } else if (SWT.getPlatform() == "gtk") {
            return "Baekmuk Batang";
        } else {
            return "Verdana";
        }
    }
}