LayoutUtil.java

package org2.eclipse.php.internal.ui.wizard.field;

import org.eclipse.jface.dialogs.IDialogConstants;
import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.swt.SWT;
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 org2.eclipse.php.internal.ui.util.PixelConverter;

public class LayoutUtil {

	/**
	 * Creates a composite and fills in the given editors.
	 * 
	 * @param labelOnTop
	 *            Defines if the label of all fields should be on top of the
	 *            fields
	 */
	public static void doDefaultLayout(final Composite parent,
			final DialogField[] editors, final boolean labelOnTop) {
		doDefaultLayout(parent, editors, labelOnTop, 0, 0);
	}

	/**
	 * Creates a composite and fills in the given editors.
	 * 
	 * @param labelOnTop
	 *            Defines if the label of all fields should be on top of the
	 *            fields
	 * @param marginWidth
	 *            The margin width to be used by the composite
	 * @param marginHeight
	 *            The margin height to be used by the composite
	 */
	public static void doDefaultLayout(final Composite parent,
			final DialogField[] editors, final boolean labelOnTop,
			final int marginWidth, final int marginHeight) {
		int nCulumns = getNumberOfColumns(editors);
		final Control[][] controls = new Control[editors.length][];
		for (int i = 0; i < editors.length; i++)
			controls[i] = editors[i].doFillIntoGrid(parent, nCulumns);
		if (labelOnTop) {
			nCulumns--;
			modifyLabelSpans(controls, nCulumns);
		}
		GridLayout layout = null;
		if (parent.getLayout() instanceof GridLayout)
			layout = (GridLayout) parent.getLayout();
		else
			layout = new GridLayout();
		if (marginWidth != SWT.DEFAULT)
			layout.marginWidth = marginWidth;
		if (marginHeight != SWT.DEFAULT)
			layout.marginHeight = marginHeight;
		layout.numColumns = nCulumns;
		parent.setLayout(layout);
	}

	public static int getButtonWidthHint(final Button button) {
		button.setFont(JFaceResources.getDialogFont());
		final PixelConverter converter = new PixelConverter(button);
		final int widthHint = converter
				.convertHorizontalDLUsToPixels(IDialogConstants.BUTTON_WIDTH);
		return Math.max(widthHint, button.computeSize(SWT.DEFAULT, SWT.DEFAULT,
				true).x);
	}

	/**
	 * Calculates the number of columns needed by field editors
	 */
	public static int getNumberOfColumns(final DialogField[] editors) {
		int nCulumns = 0;
		for (int i = 0; i < editors.length; i++)
			nCulumns = Math.max(editors[i].getNumberOfControls(), nCulumns);
		return nCulumns;
	}

	private static void modifyLabelSpans(final Control[][] controls,
			final int nCulumns) {
		for (int i = 0; i < controls.length; i++)
			setHorizontalSpan(controls[i][0], nCulumns);
	}

	/**
	 * Sets the heightHint hint of a control. Assumes that GridData is used.
	 */
	public static void setHeightHint(final Control control, final int heightHint) {
		final Object ld = control.getLayoutData();
		if (ld instanceof GridData)
			((GridData) ld).heightHint = heightHint;
	}

	/**
	 * Sets the horizontal grabbing of a control to true. Assumes that GridData
	 * is used.
	 */
	public static void setHorizontalGrabbing(final Control control) {
		final Object ld = control.getLayoutData();
		if (ld instanceof GridData)
			((GridData) ld).grabExcessHorizontalSpace = true;
	}

	/**
	 * Sets the horizontal indent of a control. Assumes that GridData is used.
	 */
	public static void setHorizontalIndent(final Control control,
			final int horizontalIndent) {
		final Object ld = control.getLayoutData();
		if (ld instanceof GridData)
			((GridData) ld).horizontalIndent = horizontalIndent;
	}

	/**
	 * Sets the span of a control. Assumes that GridData is used.
	 */
	public static void setHorizontalSpan(final Control control, final int span) {
		final Object ld = control.getLayoutData();
		if (ld instanceof GridData)
			((GridData) ld).horizontalSpan = span;
		else if (span != 1) {
			final GridData gd = new GridData();
			gd.horizontalSpan = span;
			control.setLayoutData(gd);
		}
	}

	/**
	 * Sets the width hint of a control. Assumes that GridData is used.
	 */
	public static void setWidthHint(final Control control, final int widthHint) {
		final Object ld = control.getLayoutData();
		if (ld instanceof GridData)
			((GridData) ld).widthHint = widthHint;
	}

}