Java tutorial
/** * This file Copyright (c) 2005-2008 Aptana, Inc. This program is * dual-licensed under both the Aptana Public License and the GNU General * Public license. You may elect to use one or the other of these licenses. * * This program is distributed in the hope that it will be useful, but * AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or * NONINFRINGEMENT. Redistribution, except as permitted by whichever of * the GPL or APL you select, is prohibited. * * 1. For the GPL license (GPL), you can redistribute and/or modify this * program under the terms of the GNU General Public License, * Version 3, as published by the Free Software Foundation. You should * have received a copy of the GNU General Public License, Version 3 along * with this program; if not, write to the Free Software Foundation, Inc., 51 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Aptana provides a special exception to allow redistribution of this file * with certain other free and open source software ("FOSS") code and certain additional terms * pursuant to Section 7 of the GPL. You may view the exception and these * terms on the web at http://www.aptana.com/legal/gpl/. * * 2. For the Aptana Public License (APL), this program and the * accompanying materials are made available under the terms of the APL * v1.0 which accompanies this distribution, and is available at * http://www.aptana.com/legal/apl/. * * You may view the GPL, Aptana's exception and additional terms, and the * APL in the file titled license.html at the root of the corresponding * plugin containing this source file. * * Any modifications to this file must keep this entire header intact. */ package com.aptana.ide.core.ui.dialogs; import java.io.File; import java.io.FileReader; import java.io.FileWriter; import java.io.IOException; import java.net.URI; import org.eclipse.jface.dialogs.Dialog; import org.eclipse.jface.dialogs.IDialogConstants; import org.eclipse.jface.dialogs.IInputValidator; import org.eclipse.jface.resource.StringConverter; import org.eclipse.swt.SWT; import org.eclipse.swt.custom.CCombo; import org.eclipse.swt.events.ModifyEvent; import org.eclipse.swt.events.ModifyListener; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.widgets.Button; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Control; import org.eclipse.swt.widgets.Label; import org.eclipse.swt.widgets.Shell; import org.eclipse.swt.widgets.Text; import org.eclipse.ui.IMemento; import org.eclipse.ui.XMLMemento; import com.aptana.ide.core.IdeLog; import com.aptana.ide.core.StringUtils; import com.aptana.ide.core.ui.CoreUIPlugin; /** * @author Max Stepanov * */ public class InputURLDialog extends Dialog { private static final String URL = "url"; //$NON-NLS-1$ private static final String URLS = "urls"; //$NON-NLS-1$ private static final String XML = "xml"; //$NON-NLS-1$ /** * The title of the dialog. */ private String title; /** * The message to display, or <code>null</code> if none. */ private String message; /** * The input value; the empty string by default. */ private String value = StringUtils.EMPTY; /** * The input validator, or <code>null</code> if none. */ private IInputValidator validator; /** * Ok button widget. */ private Button okButton; /** * Input combo widget. */ private CCombo combo; /** * Error message label widget. */ private Text errorMessageText; /** * Error message string. */ private String errorMessage; /** * Creates an input URL dialog with OK and Cancel buttons. Note that the dialog * will have no visual representation (no widgets) until it is told to open. * <p> * Note that the <code>open</code> method blocks for input dialogs. * </p> * * @param parentShell * the parent shell, or <code>null</code> to create a top-level * shell * @param dialogTitle * the dialog title, or <code>null</code> if none * @param dialogMessage * the dialog message, or <code>null</code> if none * @param initialValue * the initial input value, or <code>null</code> if none * (equivalent to the empty string) */ public InputURLDialog(Shell parentShell, String dialogTitle, String dialogMessage, String initialValue) { super(parentShell); this.title = dialogTitle; message = dialogMessage; if (initialValue == null) { value = StringUtils.EMPTY;//$NON-NLS-1$ } else { value = initialValue; } this.validator = new IInputValidator() { public String isValid(String newText) { try { new URI(newText).toURL(); } catch (Exception e) { return "Invalid URL"; //$NON-NLS-1$ } return null; } }; } /* * (non-Javadoc) Method declared on Dialog. */ protected void buttonPressed(int buttonId) { if (buttonId == IDialogConstants.OK_ID) { value = combo.getText(); saveMemento(); } else { value = null; } super.buttonPressed(buttonId); } /* * (non-Javadoc) * * @see org.eclipse.jface.window.Window#configureShell(org.eclipse.swt.widgets.Shell) */ protected void configureShell(Shell shell) { super.configureShell(shell); if (title != null) { shell.setText(title); } } /* * (non-Javadoc) * * @see org.eclipse.jface.dialogs.Dialog#createButtonsForButtonBar(org.eclipse.swt.widgets.Composite) */ protected void createButtonsForButtonBar(Composite parent) { // create OK and Cancel buttons by default okButton = createButton(parent, IDialogConstants.OK_ID, IDialogConstants.OK_LABEL, true); createButton(parent, IDialogConstants.CANCEL_ID, IDialogConstants.CANCEL_LABEL, false); //do this here because setting the text will set enablement on the ok // button loadList(); combo.setFocus(); if (value != null) { combo.setText(value); setErrorMessage(null); if (validator.isValid(value) != null) { Control button = getButton(IDialogConstants.OK_ID); if (button != null) { button.setEnabled(false); } } } } /* * (non-Javadoc) Method declared on Dialog. */ protected Control createDialogArea(Composite parent) { // create composite Composite composite = (Composite) super.createDialogArea(parent); // create message if (message != null) { Label label = new Label(composite, SWT.WRAP); label.setText(message); GridData data = new GridData(GridData.GRAB_HORIZONTAL | GridData.GRAB_VERTICAL | GridData.HORIZONTAL_ALIGN_FILL | GridData.VERTICAL_ALIGN_CENTER); data.widthHint = convertHorizontalDLUsToPixels(IDialogConstants.MINIMUM_MESSAGE_AREA_WIDTH); label.setLayoutData(data); label.setFont(parent.getFont()); } combo = new CCombo(composite, getInputComboStyle()); combo.setLayoutData(new GridData(GridData.GRAB_HORIZONTAL | GridData.HORIZONTAL_ALIGN_FILL)); combo.addModifyListener(new ModifyListener() { public void modifyText(ModifyEvent e) { validateInput(); } }); errorMessageText = new Text(composite, SWT.READ_ONLY | SWT.WRAP); errorMessageText.setLayoutData(new GridData(GridData.GRAB_HORIZONTAL | GridData.HORIZONTAL_ALIGN_FILL)); errorMessageText.setBackground(errorMessageText.getDisplay().getSystemColor(SWT.COLOR_WIDGET_BACKGROUND)); errorMessageText.setForeground(errorMessageText.getDisplay().getSystemColor(SWT.COLOR_RED)); // Set the error message text // See https://bugs.eclipse.org/bugs/show_bug.cgi?id=66292 setErrorMessage(errorMessage); applyDialogFont(composite); return composite; } /** * Returns the ok button. * * @return the ok button */ protected Button getOkButton() { return okButton; } /** * Returns the combo. * * @return the combo */ protected CCombo getText() { return combo; } /** * Returns the validator. * * @return the validator */ protected IInputValidator getValidator() { return validator; } /** * Returns the string typed into this input dialog. * * @return the input string */ public String getValue() { return value; } /** * Validates the input. * <p> * The default implementation of this framework method delegates the request * to the supplied input validator object; if it finds the input invalid, * the error message is displayed in the dialog's message line. This hook * method is called whenever the text changes in the input field. * </p> */ protected void validateInput() { String errorMessage = null; if (validator != null) { String text = combo.getText(); errorMessage = validator.isValid(text); } // Bug 16256: important not to treat "" (blank error) the same as null // (no error) setErrorMessage(errorMessage); } /** * Sets or clears the error message. * If not <code>null</code>, the OK button is disabled. * * @param errorMessage * the error message, or <code>null</code> to clear * @since 3.0 */ public void setErrorMessage(String errorMessage) { this.errorMessage = errorMessage; if (errorMessageText != null && !errorMessageText.isDisposed()) { errorMessageText.setText(errorMessage == null ? " \n " : errorMessage); //$NON-NLS-1$ // Disable the error message text control if there is no error, or // no error text (empty or whitespace only). Hide it also to avoid // color change. // See https://bugs.eclipse.org/bugs/show_bug.cgi?id=130281 boolean hasError = errorMessage != null && (StringConverter.removeWhiteSpaces(errorMessage)).length() > 0; errorMessageText.setEnabled(hasError); errorMessageText.setVisible(hasError); errorMessageText.getParent().update(); // Access the ok button by id, in case clients have overridden button creation. // See https://bugs.eclipse.org/bugs/show_bug.cgi?id=113643 Control button = getButton(IDialogConstants.OK_ID); if (button != null) { button.setEnabled(errorMessage == null); } } } /** * Returns the style bits that should be used for the input combo field. * Subclasses may override. * * @return the integer style bits that should be used when creating the * input combo * */ protected int getInputComboStyle() { return SWT.BORDER; } protected IMemento getMemento() { File file = CoreUIPlugin.getDefault().getStateLocation().append(URLS).addFileExtension(XML).toFile(); if (file.exists()) { try { FileReader reader = new FileReader(file); XMLMemento memento = XMLMemento.createReadRoot(reader); return memento; } catch (Exception e) { IdeLog.logError(CoreUIPlugin.getDefault(), StringUtils.EMPTY, e); } } return null; } protected void saveMemento() { XMLMemento memento = XMLMemento.createWriteRoot(URLS); saveList(memento); File file = CoreUIPlugin.getDefault().getStateLocation().append(URLS).addFileExtension(XML).toFile(); try { FileWriter writer = new FileWriter(file); memento.save(writer); } catch (IOException e) { IdeLog.logError(CoreUIPlugin.getDefault(), StringUtils.EMPTY, e); } } private final void loadList() { IMemento memento = getMemento(); if (memento == null) { return; } IMemento[] list = memento.getChildren(URL); for (int i = 0; i < list.length; ++i) { combo.add(list[i].getTextData()); } } protected final void saveList(IMemento memento) { String firstItem = combo.getText(); IMemento child = memento.createChild(URL); child.putTextData(firstItem); String[] list = combo.getItems(); for (int i = 0; i < list.length; ++i) { if (list[i].equals(firstItem)) { continue; } child = memento.createChild(URL); child.putTextData(list[i]); } } }