001// Copyright 2007-2013 The Apache Software Foundation
002//
003// Licensed under the Apache License, Version 2.0 (the "License");
004// you may not use this file except in compliance with the License.
005// You may obtain a copy of the License at
006//
007//     http://www.apache.org/licenses/LICENSE-2.0
008//
009// Unless required by applicable law or agreed to in writing, software
010// distributed under the License is distributed on an "AS IS" BASIS,
011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012// See the License for the specific language governing permissions and
013// limitations under the License.
014
015package org.apache.tapestry5.corelib.components;
016
017import org.apache.tapestry5.Block;
018import org.apache.tapestry5.ComponentResources;
019import org.apache.tapestry5.MarkupWriter;
020import org.apache.tapestry5.PropertyOverrides;
021import org.apache.tapestry5.annotations.*;
022import org.apache.tapestry5.beaneditor.PropertyModel;
023import org.apache.tapestry5.grid.ColumnSort;
024import org.apache.tapestry5.grid.GridModel;
025import org.apache.tapestry5.grid.GridSortModel;
026import org.apache.tapestry5.internal.InternalConstants;
027import org.apache.tapestry5.ioc.Messages;
028import org.apache.tapestry5.ioc.annotations.Inject;
029import org.apache.tapestry5.services.Request;
030
031import java.util.List;
032
033/**
034 * Renders out the column headers for the grid, including links (where appropriate) to control column sorting.
035 *
036 * @tapestrydoc
037 */
038@SupportsInformalParameters
039@Events(InternalConstants.GRID_INPLACE_UPDATE + " (internal event)")
040public class GridColumns
041{
042    /**
043     * The object that provides access to bean and data models, which is typically the enclosing Grid component.
044     */
045    @Parameter(value = "componentResources.container")
046    private GridModel gridModel;
047
048    /**
049     * If true, then the CSS class on each <TH> element will be omitted, which can reduce the amount of output
050     * from the component overall by a considerable amount. Leave this as false, the default, when you are leveraging
051     * the CSS to customize the look and feel of particular columns.
052     */
053    @Parameter
054    private boolean lean;
055
056    /**
057     * Where to look for informal parameter Blocks used to override column headers.  The default is to look for such
058     * overrides in the GridColumns component itself, but this is usually overridden.
059     */
060    @Parameter("this")
061    private PropertyOverrides overrides;
062
063    /**
064     * If not null, then each link is output as a link to update the specified zone.
065     */
066    @Parameter
067    private String zone;
068
069    @SuppressWarnings("unused")
070    @Component(
071            parameters = {"event=sort", "disabled=sortDisabled", "context=columnModel.id", "zone=inherit:zone"})
072    private EventLink sort;
073
074    @Inject
075    private Messages messages;
076
077    @Inject
078    private Block standardHeader;
079
080    /**
081     * Optional output parameter that stores the current column index.
082     */
083    @Parameter
084    @Property
085    private int index;
086
087    /**
088     * Caches the index of the last column.
089     */
090    private int lastColumnIndex;
091
092    @Property(write = false)
093    private PropertyModel columnModel;
094
095    @Inject
096    private ComponentResources resources;
097
098    @Inject
099    private Request request;
100
101    void setupRender()
102    {
103        lastColumnIndex = gridModel.getDataModel().getPropertyNames().size() - 1;
104    }
105
106    public boolean isSortDisabled()
107    {
108        return !columnModel.isSortable();
109    }
110
111    private ColumnSort getSortForColumn()
112    {
113        GridSortModel sortModel = gridModel.getSortModel();
114
115        String columnId = columnModel.getId();
116
117        return sortModel.getColumnSort(columnId);
118    }
119
120    void onBeginRenderFromLoop(MarkupWriter writer) {
121
122        if (!lean) {
123            writer.attributes("data-grid-property", columnModel.getId());
124        }
125        if(!isSortDisabled()){
126            switch (getSortForColumn())
127            {
128                case ASCENDING:
129                    writer.attributes("data-grid-column-sort", "ascending");
130                    break;
131  
132                case DESCENDING:
133                    writer.attributes("data-grid-column-sort", "descending");
134                default:
135                    writer.attributes("data-grid-column-sort", "sortable");
136            }
137        }
138
139        if (index == 0) {
140            writer.attributes("data-grid-column", "first");
141        }
142
143        if (index == lastColumnIndex) {
144            writer.attributes("data-grid-column", "last");
145        }
146    }
147
148    public boolean isActiveSortColumn()
149    {
150        return getSortForColumn() != ColumnSort.UNSORTED;
151    }
152
153    /**
154     * Normal, non-Ajax event handler.
155     */
156
157    boolean onSort(String columnId)
158    {
159        gridModel.getSortModel().updateSort(columnId);
160
161        if (request.isXHR())
162        {
163            resources.triggerEvent(InternalConstants.GRID_INPLACE_UPDATE, null, null);
164        }
165
166        return true;
167    }
168
169
170    public List<String> getColumnNames()
171    {
172        return gridModel.getDataModel().getPropertyNames();
173    }
174
175
176    public void setColumnName(String columnName)
177    {
178        columnModel = gridModel.getDataModel().get(columnName);
179    }
180
181
182    public Block getBlockForColumn()
183    {
184        Block override = overrides.getOverrideBlock(columnModel.getId() + "Header");
185
186        if (override != null) return override;
187
188        return standardHeader;
189    }
190
191    /**
192     * Returns null or "true", depending on whether the Grid is rendering for in-place updates or not ("true"
193     * means in-place updates). The affects whether the data-inplace-grid-links attribute will be rendered or not.
194     *
195     */
196    public String getInplaceGridLinks()
197    {
198        return zone == null ? null : "true";
199    }
200}