Using GWT 2.5.1, SimplePager.java has this method:
#Override
protected void onRangeOrRowCountChanged() {
HasRows display = getDisplay();
label.setText(createText());
// Update the prev and first buttons.
setPrevPageButtonsDisabled(!hasPreviousPage());
// Update the next and last buttons.
if (isRangeLimited() || !display.isRowCountExact()) {
setNextPageButtonsDisabled(!hasNextPage());
setFastForwardDisabled(!hasNextPages(getFastForwardPages()));
}
}
Why are the next/last buttons enabled/disabled only if range is limited or if the row count isn't exact? I have a pager set to range limited false, and my async data provider specifies that the row count is exact when I update the row count. With this setup, the next/last paging buttons will NEVER be updated!
Am I just using this wrong, or is it a bug?
I worked around the issue by subclassing SimplePager to allow me into that block at the bottom of onRangeOrRowCountChanged():
#Override
protected void onRangeOrRowCountChanged() {
boolean rangeLimited = isRangeLimited();
super.setRangeLimited(true);
super.onRangeOrRowCountChanged();
super.setRangeLimited(rangeLimited);
}
AIUI, if the range is not limited, you explicitly allow the pager to go beyond the available data and show empty pages.
If the row count is not exact, the next button should be enabled, because hasNextPage will return true (the fast-forward will be disabled though if it goes beyond the known –though inexact– number of rows). This applies whether the range is limited or not, which may or may not be a bug.
Related
I have found an interesting issue, and I am wondering if I am misusing or overlooking something. I have a large CellTable that is vertically scrollable. I want to show all the rows at once instead of traditional pagination. So at the bottom of my table I have a row that the user can click to load 50 more rows. I have provided the table with a custom table builder (setTableBuilder(new Builder());). When the user clicks "load more" I query the data, add to the ListDataProvider and call table.setVisibleRange(0, dataProvider.getList().size());.
I put a log statement in the
#Override
public void buildRowImpl(Object rowValue, int absRowIndex) {
}
method to see when it was building rows. I notice that it would build 0-dataProvider.getList().size() (all the rows), then it would build oldLength-dataProvider.getList().size() (the new rows). For instance, if I have 100 rows and then load 50 more it would build 0-150, and then rebuild 100-50. What I want is for it to only build the new rows, obviously.
So I start debugging to see why it is rebuilding the whole table each time. What I found was in com.google.gwt.user.cellview.client.HasDataPresenter it would set the "redrawRequired" flag to true at line 1325:
else if (range1 == null && range0 != null && range0.getStart() == pageStart
&& (replaceDiff >= oldRowDataCount || replaceDiff > oldPageSize)) {
// Redraw if the new data completely overlaps the old data.
redrawRequired = true;
}
So my question is why does it think that the new data completely overlaps the old data?
Am I using something incorrectly, is there a better way? This gets to be quite a slow down when it has to redraw thousands of rows that don't need to be redrawn.
Thanks,
Will
I think that, in this situation, the only way a CellTable can react to the call of the setVisibleRange() method is to redraw all rows.
You have just informed a CellTable that now it has to display new range (0-150 rows) instead of last (0-100 rows). There is no information that rows 0-100 remain unchanged and there is no need to redraw them.
The interesting thing is that you found the new rows are updated (rebuild) twice:
For instance, if I have 100 rows and then load 50 more it would build 0-150, and then rebuild 100-50
I've tried to reproduce this behavior in the smallest example:
public class ListDataProviderTest implements EntryPoint {
private static final int ADD_COUNT = 10;
private int nextVal = 0;
public void onModuleLoad() {
final CellTable<Integer> cellTable = new CellTable<Integer>();
cellTable.addColumn(new TextColumn<Integer>() {
#Override
public String getValue(Integer object) {
return object.toString();
}});
final ListDataProvider<Integer> listDataProvider = new ListDataProvider<Integer>();
listDataProvider.addDataDisplay(cellTable);
RootPanel.get().add(cellTable);
RootPanel.get().add(new Button("Add more...", new ClickHandler() {
#Override
public void onClick(ClickEvent event) {
List<Integer> list = listDataProvider.getList();
for(int i = 0; i < ADD_COUNT; i++)
list.add(nextVal++);
cellTable.setVisibleRange(0, list.size());
}
}));
}
}
But I get all the rows updated once.
Can you confirm that this example reproduces the issue or provide one that is more accurate?
AFAIK a CellTable always redraws all cells.
This is how the renderer from the CellTable works. Although it always redraws all cells, it is in most times still faster than using a FlexTable and only updating a few cells.
I have this problem with GWT: I need to skip a button from the focus cycle so I set the tab index to -1 with button.setTabIndex(-1), but in the generated html I get tabindex="0"... is this a bug?
It looks like it's on-purpose: FocusWidget's onAttach resets the tab index to 0 in onAttach when it was set to -1: https://gwt.googlesource.com/gwt/+/2.5.1/user/src/com/google/gwt/user/client/ui/FocusWidget.java
This behavior dates back to 3½ years ago (released in GWT 2.1.0): https://code.google.com/p/google-web-toolkit/source/detail?r=7642 so I'm surprised you're the first to report it (that I know of), but it indeed looks like a bug to me.
It seems it is impossible to have a negative tabindex.
At first, the doc of setTabIndex say :
Sets the widget's position in the tab index. If more than one widget
has the same tab index, each such widget will receive focus in an
arbitrary order. Setting the tab index to -1 will cause this widget to
be removed from the tab order.
And w3c say :
Elements that may receive focus should be navigated by user agents
according to the following rules:
Those elements that support the tabindex attribute and assign a positive value to it are navigated first. Navigation proceeds from the
element with the lowest tabindex value to the element with the highest
value. Values need not be sequential nor must they begin with any
particular value. Elements that have identical tabindex values should
be navigated in the order they appear in the character stream.
Those elements that do not support the tabindex attribute or support it and assign it a value of "0" are navigated next. These
elements are navigated in the order they appear in the character
stream.
Elements that are disabled do not participate in the tabbing order.
Source : http://www.w3.org/TR/1999/REC-html401-19991224/interact/forms.html#adef-tabindex
But if you want to skipe your button, try to set the tabindex < -1.
Example :
Button myButton = new Button("Hello");
myButton.setTabIndex(-2);
// "-1" is convert to 0, and the button is not skipped
I try myButton.setTabIndex(-1); and myButton.getElement.setAttribute("tabindex", "-1"), that is always convert to 0 in html.
I wish that help you.
Working with jsni.
For example:
public static native void setElementTabIndex(Element b, int ti)/*-{
b.tabIndex = ti;
}-*/;
//and call the native js function
setElementTabIndex(odButton.getElement(), -1);
As with setFocus, use deferred:
Scheduler.get().scheduleDeferred(new Command() {
#Override
public void execute() {
cb.setTabIndex(-1);
}
});
Where in my case cb = CheckBox()
When I select a row in a CellTable which contains several columns, the whole row gets colored in yellow. It does not depend on which area of the row I click (which column of the row).
What I try to do is to keep the selected row colored in yellow as long as no other row of this very table is selected. At the moment, as soon as I click somewhere else in the browser, the row gets back its original color.
I tried to use a selection model, but this changed nothing. Do you have any advise or is this simply not possible, since the focus is managed by the browser? The behavior is the same in the Google showcase for the CellTable...
The selection model actually does what you want to do: it paints a row blue and the row does not change color if you click elsewhere in the page. (Only when another row is selected)
There are 2 selection models:
One that lets you select only one row, and another one that lets you select multiple rows.
MultiSelectionModel<Row> selectionModel = new MultiSelectionModel<Row>();
table.setSelectionModel(selectionModel);
SingleSelectionModel<Row> selectionModel = new SingleSelectionModel<Row>();
table.setSelectionModel(selectionModel);
The solution of user905374 did actually work. I mentioned in my first post that I already tried the solution with a selectionModel and that it did not work. This was partially true. It does work, but only if the table does NOT contain a CheckboxCell.
Following a working and the not working example. I think this might be a bug, but I am not sure if I miss something.
final CellTable<LicenceDto> licenseTable = new CellTable<LicenceDto>();
final SingleSelectionModel<LicenceDto> selectionModel = new SingleSelectionModel<LicenceDto>();
licenseTable.setSelectionModel(selectionModel);
//--- If I add this column, the selection does work.
Column<LicenceDto, String> workingColumn = new Column<LicenceDto, String>(new TextCell()) {
#Override
public String getValue(LicenceDto object) {
return "Works";
}
};
workingColumn.setFieldUpdater(new FieldUpdater<LicenceDto, String>() {
#Override
public void update(int index, LicenceDto object, String value) {
;
}
});
licenseTable.addColumn(workingColumn);
//--- If I add this column, the selection does NOT work anymore.
Column<LicenceDto, Boolean> notWorkingColumn = new Column<LicenceDto, Boolean>(new CheckboxCell(true, true)) {
#Override
public Boolean getValue(LicenceDto object) {
return object.getEnabled();
}
};
notWorkingColumn.setFieldUpdater(new FieldUpdater<LicenceDto, Boolean>() {
#Override
public void update(int index, LicenceDto object, Boolean value) {
presenter.enableLicense(object, value);
}
});
licenseTable.addColumn(notWorkingColumn);
You can even combine multiple cells and add them to the table (e.g. LinkActionCell etc). As long as there is no CheckboxCell, the blue selection with the SingleSelectionModel does work like a charm. Does anyone see what I do wrong with this CheckboxCell or is there a bug?
UPDATE
It was simply a usage error of me. The problem was that I set handlesSelection to true (second parameter of the CheckboxCell constructor) even thought I don't handle anything. Setting it to false solves the problem.
Bottomline: Use a selection model (e.g. SingleSelectionModel) and do not set the handlesSelection parameter to true of the CheckboxCell constructor to true, if you don't handle the selection by yourself.
You should observe the Showcase demo again. This time use the checkbox on the left most column i.e the first column. On selection the row turns blue indicating the row selection is made. This is when you have SelectionModel set up. Click on the page anywhere outside the CellTable/DataGrid the selection is not changed.
Now, instead of choosing the row via checkbox from first column, you click on a row in any other column. The row turns yellow. Click on the page anywhere outside the CellTable/DataGrid the focus/yellow is lost.
"colored in yellow" indicates row is under focus and being edited and not selected.
Note - you can force row selection by using click events per cell.
Try something like this:
CellTable table;
YourDataObject object = new YourDataObject(...);
SingleSelectionModel<YourDataObject> selectionModel =
new SingleSelectionModel<YourDataObject>();
table.setSelectionModel(selectionModel);
...
table.setSelected(object, true);
Use MultiSelectionModel if you wish more than one line to be highlighted.
Store the selected row's index. When user selects row, change row's style to some "selected-style" appropriate for your case (defined in your css file) and remove selected style from the previously selected row. Also don't forget to update selected row's index.
If you provide some code from the original version I help you out with some code with pleasure.
Working in Google Web Toolkit (GWT) I am using a CellList to render the details of a list of Tariffs (using a CompositeCell to show a CheckBoxCell next to a custom cell of my own).
I want to filter the list by tariff length (12, 18, 24, 36 months etc). I would like to render a checkbox for each tariff length at the top of the list, and update the dataProvider as necessary when users uncheck and recheck a box.
I do not know in advance the set of tariff lengths, they will be extracted from the result set when the page is rendered. There could just be two (requiring two checkboxes), but possibly there could be 10 (requiring 10 checkboxes) - I only want to render a checkbox for each as needed.
So somehow I need to associate an int value with each checkbox, and then pass that int to a function that updates the list by removing all tariffs that match. I'm just not sure how to add the handler for the checkboxes and how to get the value for that particular box.
This is what I'm thinking:
// panel to hold boxes
private Panel contractLengthPanel = new HorizontalPanel();
textPanel2.add(contractLengthPanel);
// create a set of the terms, by looping the result set
Set<String> contractTerms = new HashSet<String>();
for(ElecTariff tariff : tariffs)
{
contractTerms.add(Integer.toString(tariff.getContractLength()));
}
// loop that set, creating a CheckBox for each value
for(String term : contractTerms)
{
CheckBox box = new CheckBox(term + " Months");
// set all boxes with the same name, and a unique id
box.getElement().setAttribute("name", "termBoxes");
box.getElement().setAttribute("id", "termBox" + term);
contractLengthPanel.add(box);
}
Now I'm not sure if I'm along the right lines here, but now I have each box as part of the same group (they have the same name) I would like to use that to add a handler that is called when a box is checked or unchecked, passing the box id (which contains the tariff length) to that function.
I hope this wasn't too confusingly written. Help appreciated.
There really is nothing like a "group of checkboxes" in HTML, and neither there is in GWT. There are kind of "groups of radiobuttons" though, but it's only about having their checked state mutually exclusive, it doesn't change anything to the way you work with them from code.
You have to listen to changes on each and every checkbox.
What you can do though is to use the same event handler for all your checkboxes; something like:
ValueChangeHandler<Boolean> handler = new ValueChangeHandler<Boolean>() {
#Override
public void onValueChange(ValueChangeEvent<Boolean> event) {
CheckBox box = (CheckBox) event.getSource();
String id = box.getFormValue();
boolean checked = box.getValue();
…
}
};
(note: I used getFormValue() rather than getElement().getId(); I believe it's a better choice: it's specifically made to associate a value with the checkbox)
I am facing problem with lastButton of SimplePager.
I have 3 pages in celltable, Page size=11 (1 empty record + 10 records(with value)), Total record=26.
I used CustomerPager by extending SimplePager.
In 1st attempt 1+10 records display in celltable : Next & Last page button is enabled (First & Prev button disabled) which is correct.
But LastPage button not working... :( Dont know whats the issue... (event not fires)
Strange behavior:
#1 Last page button is working only when I visit to last page(3 page in my case).
#2 Assume I am on 1st page n I moved to 2nd page(Total 3 pages in celltable). that time all buttons are enabled which is correct.
In this case Last button is working but behave like Next Button
My GWT application integrated into one of our product so cant debug it from client side.
May be index value is improper in setPage(int index) method from AbstractPager
Code flow is as follows for Last button
//From SimplePager
lastPage.addClickHandler(new ClickHandler() {
public void onClick(ClickEvent event) {
lastPage();
}
});
#Override
public void lastPage() {
super.lastPage();
}
// From AbstractPager
/**
* Go to the last page.
*/
protected void lastPage() {
setPage(getPageCount() - 1);
}
protected void setPage(int index) {
if (display != null && (!isRangeLimited || !display.isRowCountExact() || hasPage(index))) {
// We don't use the local version of setPageStart because it would
// constrain the index, but the user probably wants to use absolute page
// indexes.
int pageSize = getPageSize();
display.setVisibleRange(pageSize * index, pageSize);
}
}
or may be some conditions false from above code(from setPage())
actual record = 26 and 3 Empty record (1st Empty record/page)
May b problem with dataSize :|
How I can check number of pages based on the data size?
?
How can I solve this problem?
edit: I found out that the default constructor of the pager doesn't give you a "last" button, but a "fast forward 1000 lines" button instead (horrible, right?) .
call the following constructor like so, and see your problem solved:
SimplePager.Resources resources = GWT.create(SimplePager.Resources.class);
SimplePager simplePager = new SimplePager(TextLocation.CENTER, resources , false, 1000, true);
the first "false" flag turns off the "fastforward button" and the last "true" flag turns on the "last" button.
also the last button will work only if the pager knows the total amount of records you have.
you can call the table's setRowCount function to update the total like so:
int totalRecordsSize = 26; //the total amount of records you have
boolean isTotalExact = true; //is it an estimate or an exact match
table.setRowCount(totalRecordsSize , isTotalExact); //sets the table's total and updates the pager (assuming you called pager.setDisplay(table) before)
if you are working with an attached DataProvider, than all it's updateRowCount method instead (same usage).
Without seeing more of your code, this is a hard question to answer as there could be multiple places where things are going wrong.
I would make sure you call setDisplay(...) on your SimplePager so it has the data it needs calculate its ranges.
If you can't run in devmode, I recommend setting up some GWT logging in the browser (write the logs to a popup panel or something, see this discussion for an example).
I think the problem is related with condition in the setPage(). Try putting SOP before if condition or debug the code
Only added cellTable.setRowCount(int size, boolean isExact) in OnRange change method AsyncDataProvider. My problem is solved :)
protected void onRangeChanged(HasData<RecordVO> display) {
//----- Some code --------
cellTable.setRowCount(searchRecordCount, false);
//----- Some code --------
}