Java tutorial
package org.activityinfo.ui.client.component.form.field; /* * #%L * ActivityInfo Server * %% * Copyright (C) 2009 - 2013 UNICEF * %% * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as * published by the Free Software Foundation, either version 3 of the * License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public * License along with this program. If not, see * <http://www.gnu.org/licenses/gpl-3.0.html>. * #L% */ import com.google.common.collect.Sets; import com.google.gwt.cell.client.ValueUpdater; import com.google.gwt.event.logical.shared.ValueChangeEvent; import com.google.gwt.event.logical.shared.ValueChangeHandler; import com.google.gwt.user.client.ui.CheckBox; import com.google.gwt.user.client.ui.FlowPanel; import com.google.gwt.user.client.ui.Widget; import org.activityinfo.model.form.FormInstance; import org.activityinfo.model.form.FormInstanceLabeler; import org.activityinfo.model.resource.ResourceId; import org.activityinfo.model.type.Cardinality; import org.activityinfo.model.type.FieldType; import org.activityinfo.model.type.ReferenceType; import org.activityinfo.model.type.ReferenceValue; import org.activityinfo.promise.Promise; import org.activityinfo.ui.client.widget.RadioButton; import java.util.ArrayList; import java.util.Date; import java.util.List; import java.util.Set; /** * @author yuriyz on 2/11/14. */ public class CheckBoxFieldWidget implements ReferenceFieldWidget { private final FlowPanel panel; private final List<CheckBox> controls; private final List<FormInstance> range; public CheckBoxFieldWidget(ReferenceType type, List<FormInstance> range, final ValueUpdater valueUpdater) { panel = new FlowPanel(); controls = new ArrayList<>(); this.range = range; ValueChangeHandler<Boolean> changeHandler = new ValueChangeHandler<Boolean>() { @Override public void onValueChange(ValueChangeEvent<Boolean> event) { valueUpdater.update(updatedValue()); } }; String groupId = Long.toString(new Date().getTime()); for (final FormInstance instance : range) { CheckBox checkBox = createControl(groupId, instance, type.getCardinality()); checkBox.addValueChangeHandler(changeHandler); panel.add(checkBox); controls.add(checkBox); } } private CheckBox createControl(String groupId, FormInstance instance, Cardinality cardinality) { final CheckBox checkBox; final String label = FormInstanceLabeler.getLabel(instance); if (cardinality == Cardinality.SINGLE) { checkBox = new RadioButton(groupId, label); } else { checkBox = new CheckBox(label); } checkBox.setFormValue(instance.getId().asString()); return checkBox; } @Override public void setReadOnly(boolean readOnly) { for (CheckBox control : controls) { control.setEnabled(!readOnly); } } private ReferenceValue updatedValue() { final Set<ResourceId> value = Sets.newHashSet(); for (CheckBox control : controls) { if (control.getValue()) { value.add(ResourceId.valueOf(control.getFormValue())); } } return new ReferenceValue(value); } @Override public Promise<Void> setValue(ReferenceValue value) { Set<ResourceId> ids = value.getResourceIds(); for (CheckBox entry : controls) { ResourceId resourceId = ResourceId.valueOf(entry.getFormValue()); entry.setValue(ids.contains(resourceId)); } return Promise.done(); } @Override public void clearValue() { setValue(ReferenceValue.EMPTY); } @Override public void setType(FieldType type) { } @Override public Widget asWidget() { return panel; } }