Java tutorial
// Copyright 2010 Google Inc. All Rights Reseved. // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. package com.google.testing.testify.risk.frontend.client.view.widgets; import com.google.gwt.event.dom.client.BlurEvent; import com.google.gwt.event.dom.client.BlurHandler; import com.google.gwt.event.dom.client.ClickEvent; import com.google.gwt.event.dom.client.ClickHandler; import com.google.gwt.event.dom.client.KeyCodes; import com.google.gwt.event.dom.client.KeyDownEvent; import com.google.gwt.event.dom.client.KeyDownHandler; import com.google.gwt.event.logical.shared.HasValueChangeHandlers; import com.google.gwt.event.logical.shared.ValueChangeEvent; import com.google.gwt.event.logical.shared.ValueChangeHandler; import com.google.gwt.event.shared.HandlerRegistration; import com.google.gwt.user.client.ui.Composite; import com.google.gwt.user.client.ui.DeckPanel; import com.google.gwt.user.client.ui.HasValue; import com.google.gwt.user.client.ui.HasVerticalAlignment; import com.google.gwt.user.client.ui.HorizontalPanel; import com.google.gwt.user.client.ui.Image; import com.google.gwt.user.client.ui.Label; import com.google.gwt.user.client.ui.MultiWordSuggestOracle; import com.google.gwt.user.client.ui.SuggestBox; import com.google.gwt.user.client.ui.SuggestBox.DefaultSuggestionDisplay; import java.util.Collection; /** * Displays a label with a little delete X as well. You can click the X to delete the label. * * @author jimr@google.com (Jim Reardon) */ public class LabelWidget extends Composite implements HasValue<String>, HasValueChangeHandlers<String> { private HorizontalPanel contentPanel = new HorizontalPanel(); private Image image = new Image(); // The deck panel will have to entries -- the view mode, and the edit mode. DeckPanel will // only make one visible at a time. private DeckPanel deckPanel = new DeckPanel(); private MultiWordSuggestOracle oracle = new MultiWordSuggestOracle(" -"); private SuggestBox inputBox = new SuggestBox(oracle); private Label label = new Label(); private static final int VIEW_MODE = 0; private static final int EDIT_MODE = 1; private boolean canEdit = false; public LabelWidget(String text) { this(text, false); } /** * Constructs a label for a given object, allowing customized styling. The constructed * label will use styles: * tty-GenericLabel * tty-GenericLabelRemoveLabelImage * @param text the textual representation for this label. * @param isAddWidget true if this is a "new label..." widget, false if not. */ public LabelWidget(String text, final boolean isAddWidget) { DefaultSuggestionDisplay suggestionDisplay = (DefaultSuggestionDisplay) inputBox.getSuggestionDisplay(); suggestionDisplay.setPopupStyleName("tty-SuggestBoxPopup"); contentPanel.addStyleName("tty-RemovableLabel"); if (isAddWidget) { // Craft a little plus image. image.setStyleName("tty-RemovableLabelAddImage"); image.setUrl("images/collapsed_12.png"); image.addClickHandler(new ClickHandler() { @Override public void onClick(ClickEvent event) { switchMode(EDIT_MODE); } }); contentPanel.add(image); } // Craft the view mode. label.setText(text); label.addClickHandler(new ClickHandler() { @Override public void onClick(ClickEvent arg0) { switchMode(EDIT_MODE); } }); deckPanel.add(label); // Craft the edit mode. if (!isAddWidget) { inputBox.setText(text); } inputBox.getTextBox().addBlurHandler(new BlurHandler() { @Override public void onBlur(BlurEvent arg0) { switchMode(VIEW_MODE); } }); inputBox.getTextBox().addKeyDownHandler(new KeyDownHandler() { @Override public void onKeyDown(KeyDownEvent event) { if (event.getNativeKeyCode() == KeyCodes.KEY_ENTER) { switchMode(VIEW_MODE); } else if (event.getNativeKeyCode() == KeyCodes.KEY_ESCAPE) { if (isAddWidget) { inputBox.setText(""); } else { inputBox.setText(label.getText()); } switchMode(VIEW_MODE); } } }); // Explicitly does not call switchMode to avoid logic inside that function that would think // we have switched from edit mode to view mode. deckPanel.showWidget(VIEW_MODE); deckPanel.add(inputBox); contentPanel.add(deckPanel); if (!isAddWidget) { // Craft the delete button. image.setStyleName("tty-RemovableLabelDeleteImage"); image.setUrl("images/x.png"); image.addClickHandler(new ClickHandler() { @Override public void onClick(ClickEvent event) { setValue(null, true); } }); contentPanel.add(image); } // Set some alignments to make the widget pretty. contentPanel.setCellVerticalAlignment(label, HasVerticalAlignment.ALIGN_MIDDLE); contentPanel.setCellVerticalAlignment(image, HasVerticalAlignment.ALIGN_MIDDLE); initWidget(contentPanel); } private void switchMode(int mode) { // Just keep them in view mode if they can't edit this widget. if (!canEdit) { deckPanel.showWidget(VIEW_MODE); return; } if (mode == VIEW_MODE) { String text = inputBox.getText(); if (!text.equals(label.getText())) { // Don't save an empty label. if (!"".equals(text)) { // We have updates to save. setValue(inputBox.getText(), true); } } } int width = label.getOffsetWidth(); deckPanel.showWidget(mode); if (mode == EDIT_MODE) { inputBox.setWidth(String.valueOf(String.valueOf(width)) + "px"); inputBox.setFocus(true); } } public void setEditable(boolean canEdit) { this.canEdit = canEdit; image.setVisible(canEdit); } /** * Sets the list of suggestions for the autocomplete box. * @param suggestions list of items to suggest off of. */ public void setLabelSuggestions(Collection<String> suggestions) { oracle.clear(); oracle.addAll(suggestions); } @Override public String getValue() { return label.getText(); } @Override public void setValue(String value) { setValue(value, false); } @Override public void setValue(String value, boolean fireEvents) { String old = label.getText(); label.setText(value); inputBox.setText(value); if (fireEvents) { ValueChangeEvent.fireIfNotEqual(this, old, value); } } /** * Will fire when value of text changes or delete is clicked (the value will be null if deleted). */ @Override public HandlerRegistration addValueChangeHandler(ValueChangeHandler<String> handler) { return addHandler(handler, ValueChangeEvent.getType()); } }