examples/org.eclipse.ocl.examples.debug.vm.ui/src/org/eclipse/ocl/examples/debug/vm/ui/pages/SWTFactory.java

/*******************************************************************************
 * Copyright (c) 2014, 2016 Willink Transformations and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     R.Dvorak and others - QVTo debugger framework
 *     E.D.Willink - revised API for OCL debugger framework
 *******************************************************************************/
package org.eclipse.ocl.examples.debug.vm.ui.pages;

import org.eclipse.jface.dialogs.Dialog;
import org.eclipse.jface.dialogs.DialogPage;
import org.eclipse.jface.dialogs.IDialogConstants;
import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.FontMetrics;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.layout.GridData;
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.Group;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Text;

/**
 * Based on the SWTFactory from JDT.
 */
public class SWTFactory {
	/**
	 * Creates a new text widget
	 *
	 * @param parent
	 *            the parent composite to add this text widget to
	 * @param style
	 *            the style bits for the text widget
	 * @param hspan
	 *            the horizontal span to take up on the parent composite
	 * @param text
	 *            the initial text, not <code>null</code>
	 * @return the new text widget
	 */
	public static Text createText(Composite parent, int style, int hspan,
			String text) {
		Text t = new Text(parent, style);
		t.setFont(parent.getFont());
		GridData gd = new GridData(GridData.FILL_HORIZONTAL);
		gd.horizontalSpan = hspan;
		t.setLayoutData(gd);
		t.setText(String.valueOf(text));
		return t;
	}

	/**
	 * Creates a Composite widget
	 *
	 * @param parent
	 *            the parent composite to add this composite to
	 * @param columns
	 *            the number of columns within the composite
	 * @param hspan
	 *            the horizontal span the composite should take up on the parent
	 * @param fill
	 *            the style for how this composite should fill into its parent
	 *            Can be one of <code>GridData.FILL_HORIZONAL</code>,
	 *            <code>GridData.FILL_BOTH</code> or
	 *            <code>GridData.FILL_VERTICAL</code>
	 * @param marginwidth
	 *            the width of the margin to place around the composite (default
	 *            is 5, specified by GridLayout)
	 * @param marginheight
	 *            the height of the margin to place around the composite
	 *            (default is 5, specified by GridLayout)
	 * @return the new group
	 */
	public static Composite createComposite(Composite parent, Font font,
			int columns, int hspan, int fill, int marginwidth, int marginheight) {
		Composite g = new Composite(parent, SWT.NONE);
		GridLayout layout = new GridLayout(columns, false);
		layout.marginWidth = marginwidth;
		layout.marginHeight = marginheight;
		g.setLayout(layout);
		g.setFont(font);
		GridData gd = new GridData(fill);
		gd.horizontalSpan = hspan;
		g.setLayoutData(gd);
		return g;
	}

	/**
	 * Creates a check box button using the parents' font
	 *
	 * @param parent
	 *            the parent to add the button to
	 * @param label
	 *            the label for the button
	 * @param image
	 *            the image for the button
	 * @param checked
	 *            the initial checked state of the button
	 * @param hspan
	 *            the horizontal span to take up in the parent composite
	 * @return a new checked button set to the initial checked state
	 */
	public static Button createCheckButton(Composite parent, String label,
			Image image, boolean checked, int hspan) {
		Button button = new Button(parent, SWT.CHECK);
		button.setFont(parent.getFont());
		button.setSelection(checked);
		if (image != null) {
			button.setImage(image);
		}
		if (label != null) {
			button.setText(label);
		}
		GridData gd = new GridData();
		gd.horizontalSpan = hspan;
		button.setLayoutData(gd);
		SWTFactory.setButtonDimensionHint(button);
		return button;
	}

	/**
	 * Creates a new label widget
	 *
	 * @param parent
	 *            the parent composite to add this label widget to
	 * @param text
	 *            the text for the label
	 * @param hspan
	 *            the horizontal span to take up in the parent composite
	 * @return the new label
	 */
	public static Label createLabel(Composite parent, String text, int hspan) {
		Label l = new Label(parent, SWT.NONE);
		l.setFont(parent.getFont());
		l.setText(text);
		GridData gd = new GridData();
		gd.horizontalSpan = hspan;
		l.setLayoutData(gd);
		return l;
	}

	/**
	 * Creates and returns a new radio button with the given label.
	 *
	 * @param parent
	 *            parent control
	 * @param label
	 *            button label or <code>null</code>
	 * @param hspan
	 *            the number of columns to span in the parent composite
	 *
	 * @return a new radio button
	 */
	public static Button createRadioButton(Composite parent, String label,
			int hspan) {
		Button button = new Button(parent, SWT.RADIO);
		button.setFont(parent.getFont());
		if (label != null) {
			button.setText(label);
		}
		GridData gd = new GridData(GridData.BEGINNING);
		gd.horizontalSpan = hspan;
		button.setLayoutData(gd);
		SWTFactory.setButtonDimensionHint(button);
		return button;
	}

	/**
	 * Creates a Group widget
	 *
	 * @param parent
	 *            the parent composite to add this group to
	 * @param text
	 *            the text for the heading of the group
	 * @param columns
	 *            the number of columns within the group
	 * @param hspan
	 *            the horizontal span the group should take up on the parent
	 * @param fill
	 *            the style for how this composite should fill into its parent
	 *            Can be one of <code>GridData.FILL_HORIZONAL</code>,
	 *            <code>GridData.FILL_BOTH</code> or
	 *            <code>GridData.FILL_VERTICAL</code>
	 * @return the new group
	 */
	public static Group createGroup(Composite parent, String text, int columns,
			int hspan, int fill) {
		Group g = new Group(parent, SWT.NONE);
		g.setLayout(new GridLayout(columns, false));
		g.setText(text);
		g.setFont(parent.getFont());
		GridData gd = new GridData(fill);
		gd.horizontalSpan = hspan;
		g.setLayoutData(gd);
		return g;
	}

	/**
	 * Sets width and height hint for the button control. <b>Note:</b> This is a
	 * NOP if the button's layout data is not an instance of
	 * <code>GridData</code>.
	 *
	 * @param button
	 *            button for which to set the dimension hint
	 */
	public static void setButtonDimensionHint(Button button) {
		Object gd = button.getLayoutData();
		if (gd instanceof GridData) {
			((GridData) gd).widthHint = getButtonWidthHint(button);
			((GridData) gd).horizontalAlignment = GridData.FILL;
		}
	}

	/**
	 * Returns a width hint for a button control.
	 */
	public static int getButtonWidthHint(Button button) {
		button.setFont(JFaceResources.getDialogFont());
		PixelConverter converter = new PixelConverter(button);
		int widthHint = converter
				.convertHorizontalDLUsToPixels(IDialogConstants.BUTTON_WIDTH);
		return Math.max(widthHint, button.computeSize(SWT.DEFAULT, SWT.DEFAULT,
				true).x);
	}

	private static class PixelConverter {

		private FontMetrics fFontMetrics;

		public PixelConverter(Control control) {
			GC gc = new GC(control);
			gc.setFont(control.getFont());
			fFontMetrics = gc.getFontMetrics();
			gc.dispose();
		}

		/**
		 * @see DialogPage#convertHorizontalDLUsToPixels
		 */
		public int convertHorizontalDLUsToPixels(int dlus) {
			return Dialog.convertHorizontalDLUsToPixels(fFontMetrics, dlus);
		}

		/**
		 * @see DialogPage#convertWidthInCharsToPixels
		 *
		public int convertWidthInCharsToPixels(int chars) {
			return Dialog.convertWidthInCharsToPixels(fFontMetrics, chars);
		} */
	}
}