Java tutorial
package com.chinarewards.gwt.license.client.widget; import java.util.ArrayList; import java.util.Comparator; import java.util.List; import com.chinarewards.gwt.license.util.StringUtil; import com.google.gwt.cell.client.Cell; import com.google.gwt.cell.client.FieldUpdater; import com.google.gwt.cell.client.ValueUpdater; import com.google.gwt.core.client.GWT; import com.google.gwt.resources.client.ImageResource; import com.google.gwt.resources.client.ImageResource.ImageOptions; import com.google.gwt.resources.client.ImageResource.RepeatStyle; import com.google.gwt.user.cellview.client.CellTable; import com.google.gwt.user.cellview.client.Column; import com.google.gwt.user.cellview.client.TextHeader; public class ListCellTable<T> extends CellTable<T> { private static final int DEFAULT_PAGESIZE = 15; private static Resources DEFAULT_RESOURCES; public ListCellTable() { super(DEFAULT_PAGESIZE, getDefaultResources()); } public ListCellTable(int pageSize, Resources resources) { super(pageSize, resources); // TODO Auto-generated constructor stub } public ListCellTable(int pageSize) { super(pageSize, getDefaultResources()); } /** * A ClientBundle that provides images for this widget. */ public static interface Resources extends CellTable.Resources { /** * The background used for header cells. */ @Source("trbg.jpg") @ImageOptions(repeatStyle = RepeatStyle.Horizontal) ImageResource cellTableHeaderBackground(); /** * The styles used in this widget. */ // @Source("listCellTable.css") // Style cellTableStyle(); } private static Resources getDefaultResources() { if (DEFAULT_RESOURCES == null) { DEFAULT_RESOURCES = GWT.create(Resources.class); } return DEFAULT_RESOURCES; } /** * @author yanxin * @since 0.2.0 2011-01-15 */ private final List<SortableHeader> allHeaders = new ArrayList<SortableHeader>(); /** * @author nicho * @since 201226 15:55:51 */ private final List<TextHeader> allTextHeaders = new ArrayList<TextHeader>(); /** * Just show text , no need sorting. * * @param <C> * @param text * @param cell * @param getter * @return */ public <C extends Comparable<C>> Column<T, C> addColumn(final String text, final Cell<C> cell, final GetValue<T, C> getter) { return addColumn(text, cell, getter, null, null, null, null, null); } /** * Show text, need sorting. * * @param <C> * @param text * @param cell * @param getter * @param ref * @param sortingText * @return */ public <C extends Comparable<C>> Column<T, C> addColumn(final String text, final Cell<C> cell, final GetValue<T, C> getter, final Sorting<T> ref, final String sortingText) { return addColumn(text, cell, getter, null, createColumnComparator(getter, false), createColumnComparator(getter, true), ref, sortingText); } /** * Button or others, need event. * * @param <C> * @param text * @param cell * @param getter * @param fieldUpdater * @return */ public <C extends Comparable<C>> Column<T, C> addColumn(final String text, final Cell<C> cell, final GetValue<T, C> getter, final FieldUpdater<T, C> fieldUpdater) { return addColumn(text, cell, getter, fieldUpdater, null, null, null, null); } /** * Button or other click text , need sorting. * * @param <C> * @param text * @param cell * @param getter * @param fieldUpdater * @param ref * @param sortingText * @return */ public <C extends Comparable<C>> Column<T, C> addColumn(final String text, final Cell<C> cell, final GetValue<T, C> getter, final FieldUpdater<T, C> fieldUpdater, final Sorting<T> ref, final String sortingText) { return addColumn(text, cell, getter, fieldUpdater, createColumnComparator(getter, false), createColumnComparator(getter, true), ref, sortingText); } private <C> Column<T, C> addColumn(final String text, final Cell<C> cell, final GetValue<T, C> getter, final FieldUpdater<T, C> fieldUpdater, final Comparator<T> ascComparator, final Comparator<T> descComparator, final Sorting<T> ref, final String sortingText) { // Create the column final Column<T, C> column = new Column<T, C>(cell) { @Override public C getValue(T object) { return getter.getValue(object); } }; /** * ??HeaderHeader */ if (ref != null) { final SortableHeader header = new SortableHeader(text); allHeaders.add(header); // Hook up sorting header.setUpdater(new ValueUpdater<String>() { @Override public void update(String value) { header.setSorted(true); header.toggleReverseSort(); for (SortableHeader otherHeader : allHeaders) { if (otherHeader != header) { otherHeader.setSorted(false); otherHeader.setReverseSort(true); } } // table.refreshHeaders(); // TODO remove this when // confirmed working. ListCellTable.this.redrawHeaders(); if (StringUtil.isEmpty(sortingText)) { ref.sortingCurrentPage(header.getReverseSort() ? descComparator : ascComparator); } else { ref.sortingAll(sortingText, header.getReverseSort() ? "desc" : "asc"); } } }); this.addColumn(column, header); } else { TextHeader header = new TextHeader(text); int fal = 0; for (TextHeader otherHeader : allTextHeaders) { if (otherHeader.getValue() == header.getValue()) { header = otherHeader; fal = 1; } } if (fal != 1) allTextHeaders.add(header); this.addColumn(column, header); } if (fieldUpdater != null) { column.setFieldUpdater(fieldUpdater); } return column; } private <C extends Comparable<C>> Comparator<T> createColumnComparator(final GetValue<T, C> getter, final boolean descending) { return new Comparator<T>() { @Override public int compare(T o1, T o2) { if (o1 == null && o2 == null) { return 0; } else if (o1 == null) { return descending ? 1 : -1; } else if (o2 == null) { return descending ? -1 : 1; } // Compare the column value C c1 = getter.getValue(o1); C c2 = getter.getValue(o2); if (c1 == null && c2 == null) { return 0; } else if (c1 == null) { return descending ? 1 : -1; } else if (c2 == null) { return descending ? -1 : 1; } int comparison = c1.compareTo(c2); return descending ? -comparison : comparison; } }; } }