Java tutorial
/* * Copyright 2012 GWT-Bootstrap * * 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.github.gwtbootstrap.client.ui; import java.util.ArrayList; import java.util.Collection; import java.util.HashMap; import java.util.List; import java.util.Map; import com.github.gwtbootstrap.client.ui.base.HasAlternateSize; import com.github.gwtbootstrap.client.ui.base.HasId; import com.github.gwtbootstrap.client.ui.base.HasSize; import com.github.gwtbootstrap.client.ui.base.HasStyle; import com.github.gwtbootstrap.client.ui.base.IsResponsive; import com.github.gwtbootstrap.client.ui.base.IsSearchQuery; import com.github.gwtbootstrap.client.ui.base.ResponsiveHelper; import com.github.gwtbootstrap.client.ui.base.SearchQueryStyleHelper; import com.github.gwtbootstrap.client.ui.base.SizeHelper; import com.github.gwtbootstrap.client.ui.base.Style; import com.github.gwtbootstrap.client.ui.base.StyleHelper; import com.github.gwtbootstrap.client.ui.constants.AlternateSize; import com.github.gwtbootstrap.client.ui.constants.Constants; import com.github.gwtbootstrap.client.ui.constants.Device; import com.google.gwt.editor.client.IsEditor; import com.google.gwt.editor.client.adapters.TakesValueEditor; import com.google.gwt.event.dom.client.ChangeEvent; import com.google.gwt.event.dom.client.ChangeHandler; 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.text.shared.Renderer; import com.google.gwt.user.client.ui.Composite; import com.google.gwt.user.client.ui.HasConstrainedValue; import com.google.gwt.user.client.ui.HasEnabled; import com.google.gwt.user.client.ui.HasName; import com.google.gwt.view.client.ProvidesKey; import com.google.gwt.view.client.SimpleKeyProvider; /** * The TW Bootstrap style ValueListBox * * @param <T> the value type * @author ohashi keisuke * @since 2.0.4.0 */ public class ValueListBox<T> extends Composite implements HasConstrainedValue<T>, IsEditor<TakesValueEditor<T>>, HasName, HasId, HasEnabled, HasSize, HasAlternateSize, IsSearchQuery, IsResponsive, HasStyle { private final Map<Object, Integer> valueKeyToIndex = new HashMap<Object, Integer>(); private final List<T> valueList = new ArrayList<T>(); private final Renderer<T> renderer; private final ProvidesKey<T> keyProvider; private TakesValueEditor<T> editor; private T value; public ValueListBox(Renderer<T> renderer) { this(renderer, new SimpleKeyProvider<T>()); } public ValueListBox(Renderer<T> renderer, ProvidesKey<T> keyProvider) { this.keyProvider = keyProvider; this.renderer = renderer; initWidget(new ListBox()); getListBox().addChangeHandler(new ChangeHandler() { public void onChange(ChangeEvent event) { int selectedIndex = getListBox().getSelectedIndex(); if (selectedIndex < 0) { return; } T newValue = valueList.get(selectedIndex); setValue(newValue, true); } }); } public void setName(String name) { getListBox().setName(name); } public String getName() { return getListBox().getName(); } public HandlerRegistration addValueChangeHandler(ValueChangeHandler<T> handler) { return addHandler(handler, ValueChangeEvent.getType()); } /** * Returns a {@link TakesValueEditor} backed by the ValueListBox. */ public TakesValueEditor<T> asEditor() { if (editor == null) { editor = TakesValueEditor.of(this); } return editor; } public T getValue() { return value; } public void setAcceptableValues(Collection<T> newValues) { valueList.clear(); valueKeyToIndex.clear(); ListBox listBox = getListBox(); listBox.clear(); for (T nextNewValue : newValues) { addValue(nextNewValue); } updateListBox(); } /** * Set the value and display it in the select element. Add the value to the * acceptable set if it is not already there. */ public void setValue(T value) { setValue(value, false); } public void setValue(T value, boolean fireEvents) { if (value == this.value || (this.value != null && this.value.equals(value))) { return; } T before = this.value; this.value = value; updateListBox(); if (fireEvents) { ValueChangeEvent.fireIfNotEqual(this, before, value); } } private void addValue(T value) { Object key = keyProvider.getKey(value); if (valueKeyToIndex.containsKey(key)) { throw new IllegalArgumentException("Duplicate value: " + value); } valueKeyToIndex.put(key, valueList.size()); valueList.add(value); getListBox().addItem(renderer.render(value)); assert valueList.size() == getListBox().getItemCount(); } private ListBox getListBox() { return (ListBox) getWidget(); } private void updateListBox() { Object key = keyProvider.getKey(value); Integer index = valueKeyToIndex.get(key); if (index == null) { addValue(value); } index = valueKeyToIndex.get(key); getListBox().setSelectedIndex(index); } /** * {@inheritDoc} */ @Override public String getId() { return getListBox().getId(); } /** * {@inheritDoc} */ @Override public void setId(String id) { getListBox().setId(id); } /** * {@inheritDoc} */ @Override public void setSearchQuery(boolean searchQuery) { SearchQueryStyleHelper.setSearchQuery(this, searchQuery); } /** * {@inheritDoc} */ @Override public boolean isSearchQuery() { return SearchQueryStyleHelper.isSearchQuery(this); } /** * {@inheritDoc} */ @Override public void setAlternateSize(AlternateSize size) { StyleHelper.changeStyle(this, size, AlternateSize.class); } /** * {@inheritDoc} */ @Override public void setSize(int size) { SizeHelper.setSize(this, size); } /** * {@inheritDoc} */ @Override public void setEnabled(boolean enabled) { getListBox().setEnabled(enabled); if (enabled) { removeStyleName(Constants.DISABLED); } else { addStyleName(Constants.DISABLED); } } @Override public boolean isEnabled() { return getListBox().isEnabled(); } /** * {@inheritDoc} */ @Override public void setShowOn(Device device) { ResponsiveHelper.setShowOn(this, device); } /** * {@inheritDoc} */ @Override public void setHideOn(Device device) { ResponsiveHelper.setHideOn(this, device); } /** * {@inheritDoc} */ @Override public void setStyle(Style style) { StyleHelper.setStyle(this, style); } /** * {@inheritDoc} */ @Override public void addStyle(Style style) { StyleHelper.addStyle(this, style); } /** * {@inheritDoc} */ @Override public void removeStyle(Style style) { StyleHelper.removeStyle(this, style); } }