Wicket 数据表的扩展

Question

我们可以在另一个 DataTable 中扩展一个 DataTable 吗？

我的场景是我想构建一个名为 BaseTable 的 DataTable ，其中包含三列：id、name、<代码>颜色。我想构建另外两个名为 Table1 的表，它扩展了 BaseTable 并具有另一列：size； Table2 也扩展了 BaseTable 并具有另一个复选框列。

可以做这样的事情吗？如果可能的话，您能给我一些例子或指南吗？

更新

感谢您的帮助！这似乎是我想要的答案，但我确实按照你所说的做了，但最终得到了这个错误：

WicketMessage: The component(s) below failed to render. A common problem is that you have added a component in code but forgot to reference it in the markup (thus the component will never be rendered).

1. [MarkupContainer [Component id = dt_basecontract_list]]
2. [MarkupContainer [Component id = body]]
3. [MarkupContainer [Component id = rows]]
4. [MarkupContainer [Component id = 1]]
5. [MarkupContainer [Component id = cells]]
6. [MarkupContainer [Component id = 1]]
7. [Component id = cell]
8. [MarkupContainer [Component id = 2]]
9. [Component id = cell]
10. [MarkupContainer [Component id = 3]]
11. [MarkupContainer [Component id = cell]]
12. [MarkupContainer [Component id = detail]]
13. [MarkupContainer [Component id = delete]]

如果你需要那里的信息..

基类：ContractBasePanel

// A Base Contract DataTable Panel
public class ContractBasePanel extends Panel  {

    // Inject the ApplicationFacade
    @EJB(name="applicationFacade")
    private ApplicationFacadeLocal applicationFacade;

    public ContractBasePanel(String id, ApplicationFacadeLocal applicationFacade) {
        super(id);
        add(new DefaultDataTable<Contract>("dt_basecontract_list", getColumns(), new ContractProvider(applicationFacade), 10));
    }

    protected List<IColumn<Contract>> getColumns(){
        List<IColumn<Contract>> columns = new ArrayList<IColumn<Contract>>();
        columns.add(new PropertyColumn<Contract>(new Model<String>("ContractIdentifier"), "contractIdentifier"));
        columns.add(new PropertyColumn<Contract>(new Model<String>("Assigned To"), "customer.name"));
        return columns;
    }
}

Inherited Class : ContractModelRootPanel

// A Panel which displays a DataTable of contract
public class ContractModelRootPanel extends ContractBasePanel  {

    // Inject the ApplicationFacade
    @EJB(name="applicationFacade")
    private ApplicationFacadeLocal applicationFacade;

    // Represent the Contract Object selected by clicking "detail" or "delete" link
    private Contract contractSelected;

    public ContractModelRootPanel(String id, ApplicationFacadeLocal applicationFacade) {
        super(id, applicationFacade);
        add(new DefaultDataTable<Contract>("dt_contract_list", getColumns(), new ContractProvider(applicationFacade), 10));
    }

    class ActionPanel extends Panel
    {
        public ActionPanel(String id, IModel<Contract> model)
        {
            super(id, model);
            add(new Link("detail")
            {
                @Override
                public void onClick()
                {
                    // get Contract object which contains only contract identifier
                    contractSelected = (Contract)getParent().getDefaultModelObject();
                    PageParameters pageParameters = new PageParameters();
                    pageParameters.add("contractIdentifier", contractSelected.getContractIdentifier());

                    // handle the displays message if the contract has no owner
                    if(contractSelected.getCustomer() != null)  {
                        pageParameters.add("customerName", contractSelected.getCustomer().getName());
                    }
                    else  {
                        pageParameters.add("customerName", "-Not Bound to Any Customer-");
                    }
                    setResponsePage(ContractDetail.class, pageParameters);
                }
            });

            add(new Link("delete")
            {
                @Override
                public void onClick()
                {
                    // get Contract object which contains only contract identifier
                    contractSelected = (Contract)getParent().getDefaultModelObject();
                    applicationFacade.deleteContract(contractSelected.getContractIdentifier());
                    RequestCycle rc = RequestCycle.get();
                    rc.setResponsePage(HomePage.class);
                }
            });
        }
    }

    @Override
    protected List<IColumn<Contract>> getColumns() {
        List<IColumn<Contract>> columns = super.getColumns();
        // column for "detail" and "delete" link
        columns.add(new AbstractColumn<Contract>(new Model<String>("Edits"))
                {
                    public void populateItem(Item<ICellPopulator<Contract>> cellItem, String componentId,
                        IModel<Contract> model)
                    {
                        cellItem.add(new ActionPanel(componentId, model));
                    }
                });
        return columns;
    }
}

两个类的 HTML 是相同的，除了 wicket id ，它是 dt_basecontract_list 和 dt_contract_list。

这个错误从何而来？

Answer 1

下面是一个示例：

BaseDataTable.java:

private DataTable<T> table;
private SortableDataProvider<T> provider;

public BaseDataTable(String id, IModel model){
super(id, model);
provider = new ....;
table = new DataTable<T>("datatable", getColumns(), provider, rowsPerPage);
add(table);
}

protected IColumn<T>[] getColumns(){
return new IColumn[]{
new PropertyColumn<Account>(new StringResourceModel("id",
                        null), null, "id"),
new PropertyColumn<Account>(new StringResourceModel("name",
                        null), null, "name"),
new PropertyColumn<Account>(new StringResourceModel("color",
                        null), null, "color")
}
}

其他扩展 BaseDataTable 的表，您必须重写 getColumns() 方法并在第一行中调用 super.getColumns()重写的方法。

希望我有所帮助！