I have a little piece of code which populates a CellTable from a
Type by adding the table as a DataProviders DataDisplay and by
using the DataProviders list to create a ColumnSortHandler and
corresponding Comparators... so each time the user clicks next I
populate the table in this manner with the next set of data. It all
works great apart from when the number of elements in my set of data
is greater than 15. In this case only the top 15 (ordered) elements
are displayed I.E. only 15 rows of the CellTable are visible within
the VerticalDialog. Is this a default somewhere or can I configure
this row limit. I've looked around my code and I can see places where
I have instantiated a list and this will default to 10 elements but 15
has me baffled.
I can provide code but thought this would jog a memory without the
need for boring old code.
Many thanks
Tony
This is a default yes: http://google-web-toolkit.googlecode.com/svn/javadoc/latest/com/google/gwt/user/cellview/client/CellTable.html#CellTable()
Constructs a table with a default page size of 15.
You can change it at any time with setPageSize or setVisibleRange.
Adding to Thomas Broyer answer. I always use the code below passing my CellTables/CellLists when I don't want pagination.
public static void setupOnePageList(final AbstractHasData<?> cellTable) {
cellTable.addRowCountChangeHandler(new RowCountChangeEvent.Handler() {
#Override
public void onRowCountChange(RowCountChangeEvent event) {
cellTable.setVisibleRange(new Range(0, event.getNewRowCount()));
}
});
}
Related
Field codes:
Data:
Expected result:
Actual result:
I was thinking about where I should tweak the codes to fix the issue that the first column of each has three records as other columns do.
Also, a new class name (i.e. 1A, 1B) should be added to the second sheets (i.e. the second and fourth pages).
Thanks in advance for any help!
You need something more like this:
There were two problems - a change of class causes a page break, so at that point you can't rely on on the { =mod({ MERGESEQ },3) } = 0 to show you the right place to break next. Because a column break can also cause a page break, you also have to keep count of the columns to ensure that you can insert the class name every time you have a new page.
An advantage of doing it this way is that you can easily change the number of columns and rows per page.
(I have put one other thing in there, because strictly speaking you need to initialize Class1 when you start the merge).
I am using GWT's (2.5) SimplePager class in my application, to display pre-loaded data (I know the exact row count in advance).
The issue is with the last page. Given I have, for instance, 42 elements with an initial visible range of 10.
First page is 1-10, second 11-20, third 21-30, fourth, 31-40.
The issue is that fifth page is not 41-42 (which I want, because I want to be able to scroll back and forth and "land" exactly on the same data) but 33-42.
I have tried various tinkering with overriding SimplePager / AbstractPager methods, with no success.
For instance, if I override setPageStart, do the same as com.google.gwt.user.cellview.client.AbstractPager.setPageStart(int) but with the following commented out (I think it is the culprit code):
if (isRangeLimited && display.isRowCountExact()) {
index = Math.min(index, display.getRowCount() - pageSize);
}
The last page is fine (41-42), but this erases page size forever and when I go from last page to previous page, it becomes 40-41 (expected: 31-40). This is probably because the page size is not some constant provided to the pager instance, but is calculated with the Range object which was last used ("int pageSize = range.getLength();" in setPageStart method).
Any clue on modifying the paging behavior to my needs without breaking anything ?
Thanks !
I eventually got a working solution which is simple enough.
I provided a page size (which is the maximum number of elements that could be displayed, regardless of the total number of elements available to display) to my SimplePager object. Then I overrided getPage(), hasNextPage(), hasNextPages(int), hasPreviousPages(int), nextPage(), previousPage(), setPageStart(int) to use the provided page size instead of getLength() on the Range object.
To test this more easily (still done by hand...) I used GWT's Showcase project (and ran it in dev mode).
The downside is that I had to copy the code of the overriden methods (from AbstractPager - SimplePager does nothing except calling the superclass' methods) into my Pager class.
I need to create a quarterly expense report and I am confused what layout and widgets would be useful here
Quarter 1 Quarter 2 Quarter 3
Expense 1
Expense 2
Expense 3
I understand Celltable and DataGrids, but not sure If I can have data mappings of objects in the format as above. Mainly because these tables work with objects at a row level.
I have an object with data of the entire column instead.
Any ideas/ suggestions here ?
You have many options to choose from. The most obvious one is a FlexTable, but you can also simply put three floating FlowPanels next to each other.
With GWT you should use HTML for your layouts as much as possible unless you need some specific functionality from a widget.
EDIT:
Alternatively, you can use a DataGrid with a single row, where each cell is a custom cell that renders your object.
Finally, you can use DataGrid as a regular DataGrid - just modify the logic of what is displayed in each cell. For example, a cell can render like this:
final TextColumn<Integer> quarterColumn = new TextColumn<Integer>() {
#Override
public String getValue(Integer row) {
int column = myDataGrid.getColumnIndex(quarterColumn);
QuarterObject object = quarterObjects(column - 1);
return object.getExpense(row - 1);
}
};
Then you simply populate your DataProvider with an array of Integers from 1 to the number of records in your QuarterObject.
I have a Pager extended from AbstractPager in which every time on range or row count changed I recreate NavLinks contained in it so pager looks like this:
1 2 3 … N-1 N N+1 … M-2 M-1 M
My algorithm works fine but when I start clicking on links fast (like really furiously) by the time one RangeChange event is performing (CellTable to which my pager is attached shows spin trying to fetch data on given page) there's already another ones coming to the EventBus. It results in changing current page back and forth in an infinite loop.
I tried to make paging links enabled only when current page is competely fetched by using Scheduler.get().scheduleDeferred and .scheduleFinally but with no luck.
My temporary solution is to enable paging links after 500 ms by using Scheduler.get().scheduleFixedDelay(), but I want to know how to get the exact moment of data on the current page being fully fetched.
Thanks.
If you have the same problem you need to hang LoadingChangeEvent.Handler on your CellTable, check if data is fully loaded and inform pager about it so pager can activate it's NavLinks:
pager.setDisplay(cellTable);
cellTable.addLoadingStateChangeHandler(new LoadingStateChangeEvent.Handler() {
#Override
public void onLoadingStateChanged(LoadingStateChangeEvent event) {
if (event.getLoadingState() == LoadingStateChangeEvent.LoadingState.LOADED) {
pager.activateNavLinks();
};
}
});
There's no way to do it internally in your pager since setDisplay() accepts HasRows and addLoadingStateChangeHandler() is in AbstractHasData (AbstractHasData implements HasData, HasData implements HasRows).
I really need a possibility to run some code after the whole sorting of the DataGrid is finished. Especially after the little arrow which shows if the column is sorted ascending or descending is displayed, because i need to manipulate the CSS of this arrow after it is displayed. I couldn't find the place where the arrow is really set. I tried something like this:
ListHandler<String> columnSortHandler = new ListHandler<String>(list) {
#Override
public void onColumnSort( ColumnSortEvent event ) {
super.onColumnSort( event );
// My Code here
}
};
but the code runs also before sorting finishes.
Thanks for any suggestions how to solve this problem. I am searching for a long time now but cannot find anything that helps.
EDIT: I already override the original DataGrid.Resources to provide a custom arrow-picture. I also have a complex custom header of AbstractCell<String> which supports runtime-operations and is rendered with DIV's and Image.
As you're using a ListHandler, and thus probably a ListDataProvider that will update the CellTable live (setRowData); because both ListDataProvider and CellTable (via the inner HasDataPresenter) use Scheduler#scheduleFinally(), then using Scheduler#scheduleDeferred() should be enough to guarantee that you run after them, but then you'll risk some flicker.
You could, in your custom ListHandler flush() the ListDataProvider, which will bypass one scheduleFinally and then use scheduleFinally to execute after the one of the CellTable (because flush() will call setRowData on the CellTable which will schedule the command; your command wil be scheduled after, so will run after).
You can manipulate the css resource using CellTable.Resources.
public interface TableResources extends CellTable.Resources {
#Source("up.png")
ImageResource cellTableSortAscending();
#Source("down.png")
ImageResource cellTableSortDescending();
#Source("MyCellTable.css")
CellTable.Style cellTableStyle();
}
In MyCellTable.css use the stylename and change your icon