gwt celltable paging

Question

我有celltable和simplepager。我正在对服务器进行异步调用以将数据作为列表返回。

AsyncDataProvider<Entry> provider = new AsyncDataProvider<Entry>() {
            @Override
            protected void onRangeChanged(HasData<Entry> display) {
                final int start = display.getVisibleRange().getStart();
                int length = display.getVisibleRange().getLength();

                AsyncCallback<List<Entry>> callback = new AsyncCallback<List<Entry>>() {
                    @Override
                    public void onFailure(Throwable caught) {
                        Window.alert(caught.getMessage());
                    }

                    @Override
                    public void onSuccess(List<Entry> result) {                         
                        updateRowData(start, result);
                    }
                };

                // The remote service that should be implemented
                rpcService.fetchEntries(start, length, callback);
            }
        };

在服务器端......

public List<Entry> fetchEntries(int start, int length) {
        if (start > ENTRIES.size())
            return new ArrayList<Entry>();

        int end = start + length > ENTRIES.size() ? ENTRIES.size() : start
                + length;
        ArrayList<Entry> sublist = new ArrayList<Entry>(
                (List<Entry>) ENTRIES.subList(start, end));
        return sublist;
    }

问题是我不知道aync调用返回的数据集的大小。所以我无法设置updateRowCount。所以现在，即使数据集只有24个字段，下一个按钮也始终处于活动状态。有什么想法吗？

Answer 1

如何修改RPC服务以返回标志：

class FetchEntriesResult{
  private int totalNumberOfEntries;
  private List<Entry> entries;
  //getters,setters, constructor etc...
}

您的服务方法就像：

public FetchEntriesResult fetchEntries(int start, int length) {

       if (start > ENTRIES.size())
            return new ArrayList<Entry>();

        int end = start + length > ENTRIES.size() ? ENTRIES.size() : start
                + length;
        ArrayList<Entry> sublist = new ArrayList<Entry>(
                (List<Entry>) ENTRIES.subList(start, end));
        return new FetchEntriesResult(sublist,ENTRIES.size());
}

现在您可以在客户端上使用FetchEntriesResult.getTotalNumberOfEntries()。