Java tutorial
/** * Copyright (c) 2013 Puppet Labs, Inc. and other contributors, as listed below. * 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: * Puppet Labs */ package com.puppetlabs.geppetto.pp.dsl.ui.preferences.editors; import org.eclipse.jface.fieldassist.ControlDecoration; import org.eclipse.jface.fieldassist.FieldDecoration; import org.eclipse.jface.fieldassist.FieldDecorationRegistry; import org.eclipse.jface.resource.JFaceResources; 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.layout.GridLayout; import org.eclipse.swt.widgets.Button; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Dialog; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.Event; import org.eclipse.swt.widgets.Label; import org.eclipse.swt.widgets.Listener; import org.eclipse.swt.widgets.Monitor; import org.eclipse.swt.widgets.Shell; import org.eclipse.swt.widgets.Text; public class PromptDialog extends Dialog { private Text valueText; private Button[] buttons; private ControlDecoration valueTextDecorator; protected String errorMessage = ""; public PromptDialog(Shell parent) { this(parent, 0); } public PromptDialog(Shell parent, int style) { super(parent, style); } public void clearError() { if (valueTextDecorator != null) { valueTextDecorator.hide(); } } private ControlDecoration createDecorator(Text text, String message) { ControlDecoration controlDecoration = new ControlDecoration(text, SWT.LEFT | SWT.TOP); controlDecoration.setDescriptionText(message); FieldDecoration fieldDecoration = FieldDecorationRegistry.getDefault() .getFieldDecoration(FieldDecorationRegistry.DEC_ERROR); controlDecoration.setImage(fieldDecoration.getImage()); return controlDecoration; } private void disableOk() { if (buttons != null && buttons[1] != null) buttons[1].setEnabled(false); } private void enableOk() { if (buttons != null && buttons[1] != null) buttons[1].setEnabled(true); } protected String getErrorMessage() { return errorMessage; } protected boolean isValid(String text) { return true; } protected boolean isValueRequired() { return true; } public void prompt(String title, String text, String check, final String[] value, final int[] checkValue, final int[] result) { Shell parent = getParent(); final Shell shell = new Shell(parent, SWT.SHEET | SWT.DIALOG_TRIM | SWT.APPLICATION_MODAL); if (title != null) shell.setText(title); GridLayout gridLayout = new GridLayout(); shell.setLayout(gridLayout); Label label = new Label(shell, SWT.WRAP | SWT.BOLD); label.setText(text); label.setFont(JFaceResources.getBannerFont()); GridData data = new GridData(); Monitor monitor = parent.getMonitor(); int maxWidth = monitor.getBounds().width * 2 / 3; int width = label.computeSize(SWT.DEFAULT, SWT.DEFAULT).x; data.widthHint = Math.min(width, maxWidth); data.horizontalAlignment = GridData.FILL; data.grabExcessHorizontalSpace = true; data.horizontalIndent = 15; data.verticalIndent = 15; label.setLayoutData(data); valueText = new Text(shell, SWT.BORDER); valueTextDecorator = createDecorator(valueText, "initial"); valueTextDecorator.setMarginWidth(5); valueTextDecorator.hide(); valueText.addModifyListener(new ModifyListener() { @Override public void modifyText(ModifyEvent e) { updateStatus(); } }); if (value[0] != null) valueText.setText(value[0]); data = new GridData(); width = valueText.computeSize(500, SWT.DEFAULT).x; if (width > maxWidth) data.widthHint = maxWidth; else data.widthHint = width; data.minimumWidth = 300; data.horizontalAlignment = GridData.FILL; data.horizontalIndent = 15; data.grabExcessHorizontalSpace = true; valueText.setTextLimit(200); valueText.setLayoutData(data); buttons = new Button[3]; Listener listener = new Listener() { public void handleEvent(Event event) { if (buttons[0] != null) checkValue[0] = buttons[0].getSelection() ? 1 : 0; value[0] = valueText.getText(); result[0] = event.widget == buttons[1] ? 1 : 0; shell.close(); } }; if (check != null) { buttons[0] = new Button(shell, SWT.CHECK); buttons[0].setText(check); buttons[0].setSelection(checkValue[0] != 0); data = new GridData(); data.horizontalAlignment = GridData.BEGINNING; data.horizontalIndent = 15; buttons[0].setLayoutData(data); } Composite composite = new Composite(shell, SWT.NONE); data = new GridData(); data.horizontalAlignment = GridData.CENTER; composite.setLayoutData(data); composite.setLayout(new GridLayout(2, true)); buttons[1] = new Button(composite, SWT.PUSH); buttons[1].setText(SWT.getMessage("SWT_OK")); //$NON-NLS-1$ buttons[1].setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); buttons[1].addListener(SWT.Selection, listener); buttons[2] = new Button(composite, SWT.PUSH); buttons[2].setText(SWT.getMessage("SWT_Cancel")); //$NON-NLS-1$ buttons[2].setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); buttons[2].addListener(SWT.Selection, listener); // make RETURN trigger OK shell.setDefaultButton(buttons[1]); // update status based on current value updateStatus(); shell.pack(); shell.open(); Display display = parent.getDisplay(); while (!shell.isDisposed()) { if (!display.readAndDispatch()) display.sleep(); } } public void setError(String message) { valueTextDecorator.setDescriptionText(message); valueTextDecorator.show(); valueTextDecorator.showHoverText(message); } protected void setErrorMessage(String errorMessage) { this.errorMessage = errorMessage; } private void updateStatus() { String theText = valueText.getText(); if (isValueRequired()) { if (theText.trim().length() < 1) { // do not report as an error, just disable ok, but // must clear any previous error. clearError(); disableOk(); return; } } if (isValid(theText)) { clearError(); enableOk(); } else { setError(getErrorMessage()); disableOk(); } } }