melnorme.util.swt.SWTUtil.java Source code

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Here is the source code for melnorme.util.swt.SWTUtil.java

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/*******************************************************************************
 * Copyright (c) 2007 DSource.org 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:
 *     Bruno Medeiros - initial implementation
 *******************************************************************************/
package melnorme.util.swt;

import static melnorme.utilbox.core.Assert.AssertNamespace.assertFail;

import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.Resource;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.MessageBox;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Text;

import melnorme.utilbox.status.Severity;
import melnorme.utilbox.status.StatusLevel;

/**
 * Miscelleanous SWT utilities.
 */
public class SWTUtil {

    /** @return true if a control can be used: is neither null, nor disposed. */
    public static boolean isOkToUse(Control control) {
        return control != null && !control.isDisposed();
    }

    public static void setEnabledIfOk(Control control, boolean enabled) {
        if (isOkToUse(control)) {
            control.setEnabled(enabled);
        }
    }

    public static <T extends Resource> T dispose(T resource) {
        if (resource != null) {
            resource.dispose();
        }
        return null;
    }

    /**
     * Returns the standard display to be used. The method first checks, if
     * the thread calling this method has an associated disaply. If so, this
     * display is returned. Otherwise the method returns the default display.
     */
    public static Display getStandardDisplay() {
        Display display = Display.getCurrent();
        if (display == null)
            display = Display.getDefault();
        return display;
    }

    public static boolean isUIThread() {
        return Display.getCurrent() != null;
    }

    /** Sets the enable state of the composite's children, recursively. */
    public static void recursiveSetEnabled(Composite composite, boolean enabled) {
        for (Control control : composite.getChildren()) {
            if (control instanceof Composite) {
                recursiveSetEnabled((Composite) control, enabled);
            }
            control.setEnabled(enabled);
        }
    }

    /** Runs the runnable in the SWT thread. 
     * (Simply runs the runnable if the current thread is the UI thread,
     * otherwise calls the runnable in asyncexec.) */
    public static void runInSWTThread(Runnable runnable) {
        if (Display.getCurrent() == null) {
            Display.getDefault().asyncExec(runnable);
        } else {
            runnable.run();
        }
    }

    /** Show an info (OK button) MsgBox with given title and message. */
    public static int showInfoMsgBox(Shell shell, String title, String message) {
        MessageBox messageBox = new MessageBox(shell, SWT.OK);
        messageBox.setText(title);
        messageBox.setMessage(message);
        return messageBox.open();
    }

    /**
     * Post {@link Control#setFocus()} on the UI thread, if current thread not UI thread.
     */
    public static void post_setFocus(final Text control) {
        if (!isOkToUse(control)) {
            return;
        }

        Display display = control.getDisplay();
        if (display == Display.getCurrent()) {
            control.setFocus();
        } else {
            display.asyncExec(new Runnable() {
                @Override
                public void run() {
                    if (!control.isDisposed()) {
                        control.setFocus();
                    }
                }
            });
        }
    }

    public static int statusLevelToMessageDialogKing(StatusLevel statusLevel) {
        switch (statusLevel) {
        case ERROR:
            return MessageDialog.ERROR;
        case WARNING:
            return MessageDialog.WARNING;
        case INFO:
            return MessageDialog.INFORMATION;
        case OK:
            return MessageDialog.OK;
        }
        throw assertFail();
    }

    public static Image getSWTImageForStatusLevel(StatusLevel statusLevel2) {
        return getSystemImage(getSystemImageCode(statusLevel2));
    }

    public static int getSystemImageCode(StatusLevel statusLevel) {
        switch (statusLevel) {
        case ERROR:
            return SWT.ICON_ERROR;
        case WARNING:
            return SWT.ICON_WARNING;
        case INFO:
            return SWT.ICON_INFORMATION;
        case OK:
            return SWT.ICON_WORKING;
        }
        throw assertFail();
    }

    public static Image getImageForSeverity(Severity severity) {
        switch (severity) {
        case ERROR:
            return getSystemImage(SWT.ICON_ERROR);
        case WARNING:
            return getSystemImage(SWT.ICON_WARNING);
        case INFO:
            return getSystemImage(SWT.ICON_INFORMATION);
        }
        throw assertFail();
    }

    public static Image getSystemImage(final int imageID) {
        return Display.getCurrent().getSystemImage(imageID);
    }

}