如何在 Tree Grid GXT(GWT) 列中设置图标？

Question

我正在开发 GWT 应用程序，我应该将 Tree Grid 中的默认图标更改为我自己的图标。在其他情况下，我可以轻松设置图标，但当我有树形网格时，情况并非如此。当我只有默认网格时，我设置图标的代码是这样的：

Protected List<ColumnConfig> getColumns() {
        List<ColumnConfig> columnConfigs = new ArrayList<ColumnConfig>();

        ColumnConfig columnConfig = new ColumnConfig("status", MSGS.gridUserColumnHeaderStatus(), 50);
        GridCellRenderer<GwtUser> setStatusIcon = new GridCellRenderer<GwtUser>() {

            public String render(GwtUser gwtUser, String property, ColumnData config, int rowIndex, int colIndex, ListStore<GwtUser> deviceList, Grid<GwtUser> grid) {

                KapuaIcon icon;
                if (gwtUser.getStatusEnum() != null) {
                    switch (gwtUser.getStatusEnum()) {
                    case DISABLED:
                        icon = new KapuaIcon(IconSet.USER);
                        icon.setColor(Color.RED);
                        break;
                    case ENABLED:
                        icon = new KapuaIcon(IconSet.USER);
                        icon.setColor(Color.GREEN);
                        break;
                    default:
                        icon = new KapuaIcon(IconSet.USER);
                        icon.setColor(Color.GREY);
                        break;
                    }
                } else {
                    icon = new KapuaIcon(IconSet.USER);
                    icon.setColor(Color.GREY);
                }

                return icon.getInlineHTML();
            }
        };
        columnConfig.setRenderer(setStatusIcon);
        columnConfig.setAlignment(HorizontalAlignment.CENTER);
        columnConfig.setSortable(false);
        columnConfigs.add(columnConfig);

但是当我将它应用到我的树形网格时，只有第一个项目有一个图标，我无法扩展网格。这是我当前的树网格代码

 List<ColumnConfig> configs = new ArrayList<ColumnConfig>();

        ColumnConfig column = new ColumnConfig("topicName", MSGS.topicInfoTableTopicHeader(), 150);
        column.setRenderer(new TreeGridCellRenderer<GwtTopic>());
        configs.add(column);

        column = new ColumnConfig("timestamp", MSGS.topicInfoTableLastPostedHeader(), 150);
        configs.add(column);

        store = new TreeStore<GwtTopic>();
        AsyncCallback<List<GwtTopic>> topicsCallback = new AsyncCallback<List<GwtTopic>>() {

            @Override
            public void onSuccess(List<GwtTopic> topics) {
                store.add(topics, true);
                topicInfoGrid.unmask();
            }

            @Override
            public void onFailure(Throwable t) {
                FailureHandler.handle(t);
                topicInfoGrid.unmask();
            }
        };
        dataService.findTopicsTree(currentSession.getSelectedAccount().getId(), topicsCallback);
        topicInfoGrid = new TreeGrid<GwtTopic>(store, new ColumnModel(configs));
        topicInfoGrid.setBorders(false);
        topicInfoGrid.setStateful(false);
        topicInfoGrid.setLoadMask(true);
        topicInfoGrid.mask("Loading");
        topicInfoGrid.setStripeRows(true);
        topicInfoGrid.getView().setAutoFill(true);
        topicInfoGrid.getView().setEmptyText(MSGS.topicInfoGridEmptyText());
        topicInfoGrid.disableTextSelection(false);

如何更改此代码以设置我自己的图标？

Answer 1

你可以使用 setIconProvider 方法来改变叶子的图标：

topicInfoGrid.setIconProvider(new IconProvider<GwtTopic>() {
            @Override
            public ImageResource getIcon(GwtTopic gwtTopic) {
                GwtTopicType type = gwtTopic.getType();
                if (type == GwtTopicType.Folder) {
                    if (topicInfoGrid.isExpanded(gwtTopic)) return new TopicInfoResources.Instance.iconFolderOpen();
                    else return TopicInfoResources.Instance.iconFolder();
                }
                return TopicInfoResources.Instance.user();
            }
        });

这是扩展 ClientBundle 的接口：

public interface TopicInfoResources extends ClientBundle
{
    public static final TopicInfoResources Instance = GWT.create(TopicInfoResources.class);

    @Source("folder.png")               ImageResource iconFolder();
    @Source("folder-open.png")          ImageResource iconFolderOpen();
    @Source("user.png")                 ImageResource user();
}

希望这会有所帮助！