Java tutorial
/* * Copyright 2010 JBoss Inc * * 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 org.drools.guvnor.client.table; import java.util.ArrayList; import java.util.List; import com.google.gwt.core.client.GWT; import com.google.gwt.event.dom.client.ClickEvent; import com.google.gwt.event.dom.client.ClickHandler; import com.google.gwt.event.logical.shared.CloseEvent; import com.google.gwt.event.logical.shared.CloseHandler; import com.google.gwt.event.logical.shared.ValueChangeEvent; import com.google.gwt.event.logical.shared.ValueChangeHandler; import com.google.gwt.user.cellview.client.CellTable; import com.google.gwt.user.cellview.client.Column; import com.google.gwt.user.cellview.client.Header; import com.google.gwt.user.client.ui.CheckBox; import com.google.gwt.user.client.ui.Image; import com.google.gwt.user.client.ui.PopupPanel; import com.google.gwt.user.client.ui.ToggleButton; import com.google.gwt.user.client.ui.VerticalPanel; /** * @author Geoffrey De Smet */ public class ColumnPicker<T> { private static final TableImageResources TABLE_IMAGE_RESOURCES = GWT.create(TableImageResources.class); private static final Image COLUMN_PICKER_IMAGE = new Image(TABLE_IMAGE_RESOURCES.columnPicker()); private final CellTable<T> cellTable; private List<ColumnMeta<T>> columnMetaList = new ArrayList<ColumnMeta<T>>(); public ColumnPicker(CellTable<T> cellTable) { this.cellTable = cellTable; } public void addColumn(Column<T, ?> column, Header<String> header, boolean visible) { addColumn(new ColumnMeta<T>(column, header, visible)); } private void addColumn(ColumnMeta<T> columnMeta) { columnMetaList.add(columnMeta); if (columnMeta.isVisible()) { cellTable.addColumn(columnMeta.getColumn(), columnMeta.getHeader()); } } public ToggleButton createToggleButton() { final ToggleButton button = new ToggleButton(COLUMN_PICKER_IMAGE); final PopupPanel popup = new PopupPanel(true); popup.addCloseHandler(new CloseHandler<PopupPanel>() { public void onClose(CloseEvent<PopupPanel> popupPanelCloseEvent) { button.setDown(false); } }); VerticalPanel popupContent = new VerticalPanel(); for (final ColumnMeta<T> columnMeta : columnMetaList) { final CheckBox checkBox = new CheckBox(columnMeta.getHeader().getValue()); checkBox.setValue(columnMeta.isVisible()); checkBox.addValueChangeHandler(new ValueChangeHandler<Boolean>() { public void onValueChange(ValueChangeEvent<Boolean> booleanValueChangeEvent) { boolean visible = booleanValueChangeEvent.getValue(); if (visible) { // WORKAROUND because CellTable does not support insertColumn at this time for (ColumnMeta<T> resettingColumnMeta : columnMetaList) { if (resettingColumnMeta.isVisible()) { cellTable.removeColumn(resettingColumnMeta.getColumn()); } } columnMeta.setVisible(visible); for (ColumnMeta<T> resettingColumnMeta : columnMetaList) { if (resettingColumnMeta.isVisible()) { cellTable.addColumn(resettingColumnMeta.getColumn(), resettingColumnMeta.getHeader()); } } } else { columnMeta.setVisible(visible); cellTable.removeColumn(columnMeta.getColumn()); } } }); popupContent.add(checkBox); } popup.add(popupContent); button.addClickHandler(new ClickHandler() { public void onClick(ClickEvent event) { if (button.isDown()) { popup.setPopupPosition(button.getAbsoluteLeft(), button.getAbsoluteTop() + button.getOffsetHeight()); popup.show(); } // Note: no need to hide the popup when clicked when down, // because clicking anywhere outside the popup will hide the popup } }); return button; } private static class ColumnMeta<T> { private Column<T, ?> column; private Header<String> header; private boolean visible; private ColumnMeta(Column<T, ?> column, Header<String> header, boolean visible) { this.column = column; this.header = header; this.visible = visible; } public Column<T, ?> getColumn() { return column; } public void setColumn(Column<T, ?> column) { this.column = column; } public Header<String> getHeader() { return header; } public void setHeader(Header<String> header) { this.header = header; } public boolean isVisible() { return visible; } public void setVisible(boolean visible) { this.visible = visible; } } }