Java tutorial
/******************************************************************************* * Copyright (c) 2014 Red Hat, Inc. * 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: * lufimtse : Leo Ufimtsev lufimtse@redhat.com *******************************************************************************/ package org.eclipse.linuxtools.profiling.ui; import org.eclipse.jface.dialogs.MessageDialog; import org.eclipse.swt.graphics.Image; import org.eclipse.swt.widgets.Shell; import org.eclipse.ui.PlatformUI; /** * <h1>UI sycned Message Dialogue </h1> * <p> * This class is for launching common messages <b>from background threads</b> and <b>getting a return value</b>. * </p> * <p> * When you're not in a U.I thread, getting the 'shell' causes a runtime exception. <br> * Never the less, sometimes you need user feedback when executing a background job. <br> * (e.g missing flags when launching a profiling tools, ask the user if he wants the flag to be added). <br> * This class aims to implement wrappers for the standard openTYPE message dialogues so that <br> * they could be launched from any background thread. * </p> * * <p> Note, methods in this subclass have a postfix of 'SyncedRunnable'. * @since 3.1 */ public class MessageDialogSyncedRunnable extends MessageDialog { /** * Calls parent, identical to parent implementation in all respects. <br> * <p> Neccessary to supress compiler warnings. Use static methods in this class instead </p> * <p> For details and paramater description, please see: <br> </p> * {@link org.eclipse.jface.dialogs.MessageDialog#MessageDialog(Shell, String, Image, String, int, String[], int) } * * * @param parentShell * the parent shell * @param dialogTitle * the dialog title, or <code>null</code> if none * @param dialogTitleImage * the dialog title image, or <code>null</code> if none * @param dialogMessage * the dialog message * @param dialogImageType * one of the following values: * <ul> * <li><code>MessageDialog.NONE</code> for a dialog with no * image</li> * <li><code>MessageDialog.ERROR</code> for a dialog with an * error image</li> * <li><code>MessageDialog.INFORMATION</code> for a dialog * with an information image</li> * <li><code>MessageDialog.QUESTION </code> for a dialog with a * question image</li> * <li><code>MessageDialog.WARNING</code> for a dialog with a * warning image</li> * </ul> * @param dialogButtonLabels * an array of labels for the buttons in the button bar * @param defaultIndex * the index in the button label array of the default button */ protected MessageDialogSyncedRunnable(Shell parentShell, String dialogTitle, Image dialogTitleImage, String dialogMessage, int dialogImageType, String[] dialogButtonLabels, int defaultIndex) { super(parentShell, dialogTitle, dialogTitleImage, dialogMessage, dialogImageType, dialogButtonLabels, defaultIndex); } /** * <h1>Open Question Dialogue.</h1> * <p> * Identical to parent implementation {@link MessageDialog#openQuestion(Shell, String, String) openQuestion} <br> * except that you do not need to provide a shell. * </p> * <p> * Convenience method to open a simple Yes/No question dialog. * </p> * * @param title the dialog's title, or <code>null</code> if none * @param message the message * @return <code>true </code> if the user presses the Yes button, * <code>false</code> otherwise */ public static boolean openQuestionSyncedRunnable(final String title, final String message) { return openInSyncedRunnable(DialogueType.QUESTION, title, message); } /** * <h1>Open Confirmation Dialogue. </h1> * <p> * Identical to parent implementation {@link MessageDialog#openConfirm(Shell, String, String) openConfirm}<br> * except that you do not need to provide a shell. * </p> * * <p> Convenience method to open a simple confirm (OK/Cancel) dialog. </p> * * @param title the dialog's title, or <code>null</code> if none * @param message the message * @return <code>true</code> if the user presses the OK button, * <code>false</code> otherwise */ public static boolean openConfirmSyncedRunnable(final String title, final String message) { return openInSyncedRunnable(DialogueType.CONFIRMATION, title, message); } /** * <h1>Open Information Dialogue.</h1> * <p> * Identical to parent implementation {@link MessageDialog#openInformation(Shell, String, String) openInformation} <br> * except that you do not need to provide a shell. * </p> * <p> * Convenience method to open a simple confirm (OK/Cancel) dialog. * </p> * * @param title the dialog's title, or <code>null</code> if none * @param message the message */ public static void openInformationSyncedRunnable(final String title, final String message) { //We discard boolean and don't return anything. openInSyncedRunnable(DialogueType.INFO, title, message); } /** * <h1>Open Error Dialogue.</h1> * <p> * Identical to parent implementation {@link MessageDialog#openError(Shell, String, String) openError}<br> * except that you do not need to provide a shell: * </p> *<p> *Convenience method to open a standard error dialog. *</p> * * @param title the dialog's title, or <code>null</code> if none * @param message the message */ public static void openErrorSyncedRunnable(final String title, final String message) { //We discard boolean and don't return anything. openInSyncedRunnable(DialogueType.ERROR, title, message); } private static enum DialogueType { INFO, ERROR, CONFIRMATION, QUESTION } /* To prevent code duplication... */ private static boolean openInSyncedRunnable(final DialogueType type, final String title, final String message) { //We define a 'final' variable that will be accessible in the runnable object. final BooleanWithGetSet userChoiceBool = new BooleanWithGetSet(false); //To generate U.I, we make a syncronised call the U.I thread, //otherwise we get an U.I exception. PlatformUI.getWorkbench().getDisplay().syncExec(() -> { Shell parent = PlatformUI.getWorkbench().getDisplay().getActiveShell(); switch (type) { case INFO: MessageDialog.openInformation(parent, title, message); break; case ERROR: MessageDialog.openError(parent, title, message); break; case CONFIRMATION: boolean okPressed = MessageDialog.openConfirm(parent, title, message); userChoiceBool.setVal(okPressed); break; case QUESTION: boolean okPressedQ = MessageDialog.openQuestion(parent, title, message); userChoiceBool.setVal(okPressedQ); break; default: break; } return; }); return userChoiceBool.getVal(); } }