Java tutorial
/******************************************************************************* * Copyright (c) 2000, 2003 IBM Corporation and others. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Common Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/cpl-v10.html * * Contributors: * IBM Corporation - initial API and implementation *******************************************************************************/ package net.sf.jmoney.gnucashXML; import org.eclipse.jface.dialogs.Dialog; import org.eclipse.jface.dialogs.IDialogConstants; import org.eclipse.jface.dialogs.IInputValidator; import org.eclipse.swt.SWT; 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; /** * A simple input dialog for soliciting an input string * from the user. * <p> * This concete dialog class can be instantiated as is, * or further subclassed as required. * </p> */ public class AccountChooser extends Dialog { /** * 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 = "";//$NON-NLS-1$ /** * The input validator, or <code>null</code> if none. */ private IInputValidator validator; /** * Ok button widget. */ private Button okButton; /** * Input text widget. */ private Text text; /** * Error message label widget. */ private Label errorMessageLabel; /** * Creates an input 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 * @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) * @param validator an input validator, or <code>null</code> if none */ public AccountChooser(Shell parentShell, String dialogMessage) { super(parentShell); String dialogTitle = "JMoney: Choose account"; this.title = dialogTitle; message = dialogMessage; String initialValue = "Hello from the JMoney team"; IInputValidator validator = null; if (initialValue == null) value = "";//$NON-NLS-1$ else value = initialValue; this.validator = validator; } /* (non-Javadoc) * Method declared on Dialog. */ protected void buttonPressed(int buttonId) { if (buttonId == IDialogConstants.OK_ID) { value = text.getText(); } else { value = null; } super.buttonPressed(buttonId); } /* (non-Javadoc) * Method declared in Window. */ protected void configureShell(Shell shell) { super.configureShell(shell); if (title != null) shell.setText(title); } /* (non-Javadoc) * Method declared on Dialog. */ 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 text.setFocus(); if (value != null) { text.setText(value); text.selectAll(); } } /* (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()); } text = new Text(composite, SWT.SINGLE | SWT.BORDER); text.setLayoutData(new GridData(GridData.GRAB_HORIZONTAL | GridData.HORIZONTAL_ALIGN_FILL)); text.addModifyListener(new ModifyListener() { public void modifyText(ModifyEvent e) { validateInput(); } }); text.setFont(parent.getFont()); errorMessageLabel = new Label(composite, SWT.NONE); errorMessageLabel.setLayoutData(new GridData(GridData.GRAB_HORIZONTAL | GridData.HORIZONTAL_ALIGN_FILL)); errorMessageLabel.setFont(parent.getFont()); return composite; } /** * Returns the error message label. * * @return the error message label */ protected Label getErrorMessageLabel() { return errorMessageLabel; } /** * Returns the ok button. * * @return the ok button */ protected Button getOkButton() { return okButton; } /** * Returns the text area. * * @return the text area */ protected Text getText() { return text; } /** * 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) { errorMessage = validator.isValid(text.getText()); } // Bug 16256: important not to treat "" (blank error) the same as null (no error) errorMessageLabel.setText(errorMessage == null ? "" : errorMessage); //$NON-NLS-1$ okButton.setEnabled(errorMessage == null); errorMessageLabel.getParent().update(); } }