I had my data in a FlexTable, but am migrating to a DataGrid so I can easily add pagination. I get the data via a REST call. I can't seem to get the data to actually display. Here are the relevant snippets:
private DataGrid<SearchResult> resultsGrid = new DataGrid<SearchResult>();
resultsGrid.setAutoHeaderRefreshDisabled(true);
TextColumn<SearchResult> titleColumn = new TextColumn<SearchResult>() {
#Override
public String getValue(SearchResult object) {
return object.getTitle();
}
};
resultsGrid.addColumn(titleColumn, "Document Title");
ButtonCell buttonCell = new ButtonCell();
Column<SearchResult, String> buttonColumn = new Column<SearchResult, String>(buttonCell){
#Override
public String getValue(SearchResult object) {
return "Show";
}
};
resultsGrid.addColumn(buttonColumn, "");
buttonColumn.setFieldUpdater(new FieldUpdater<SearchResult, String>() {
public void update(int index, SearchResult object, String value) {
doPreview(object.title);
}
});
TextColumn<SearchResult> roleColumn = new TextColumn<SearchResult>() {
#Override
public String getValue(SearchResult object) {
return object.getRoles();
}
#Override
public String getCellStyleNames(Context context, SearchResult object) {
if (object.containsCurrentRole)
return "highlight";
else
return null;
}
};
resultsGrid.addColumn(roleColumn, "Associated Roles");
final SingleSelectionModel<SearchResult> selectionModel = new SingleSelectionModel<SearchResult>();
resultsGrid.setSelectionModel(selectionModel);
selectionModel.addSelectionChangeHandler(new SelectionChangeEvent.Handler() {
public void onSelectionChange(SelectionChangeEvent event) {
SearchResult selected = selectionModel.getSelectedObject();
if (selected != null) {
clearWordCloud();
getWordCloud(selected.getTitle());
}
}
});
dataProvider.addDataDisplay(resultsGrid);
// Create a Pager to control the table.
SimplePager.Resources pagerResources = GWT.create(SimplePager.Resources.class);
pager = new SimplePager(TextLocation.CENTER, pagerResources, false, 0, true);
pager.setDisplay(resultsGrid);
resultsGrid.setVisible(true);
resultsGrid.addStyleName("results");
mainPanel.add(resultsGrid);
...
The function that gets called after a search:
private void updateTable(List<SearchResult> results) {
dataProvider.getList().addAll(results);
dataProvider.refresh();
dataProvider.flush();
resultsGrid.setVisible(true);
resultsFlexTable.setVisible(true);
}
At first I was missing the flush and refresh, but adding them had no effect. I'm kind of stumped.
The most likely problem is that your DataGrid has a height of zero. DataGrid implements RequiresResize, which means that its height either has to be set explicitly, or it will acquire its height from a parent widget if this parent widget implements ProvidesResize. FlexTable does not implement ProvidesResize interface.
NB: You don't need flush and refresh - adding data to the DataProvider refreshes the grid.
Related
I have two buttons(edit + delete) in one column.
ButtonCell functionButtonCell = new ButtonCell() {
#Override
public void render(final Context context, final SafeHtml data, final SafeHtmlBuilder sb) {
sb.appendHtmlConstant("<button type='button' class='gwt-Button' style = 'width:60px;margin:1px;'>Edit</button>");
sb.appendHtmlConstant("<br/>");
sb.appendHtmlConstant("<button type='button' class='gwt-Button' style = 'width:60px;margin:1px;'>Delete</button>");
}
};
functionColumn = new Column<AdminModel, String>(functionButtonCell) {
public String getValue(final AdminModel object) {
return object.getSeq().toString();
}
};
Bind event for this column in Presenter as
.........
view.getFunctionColumn().setFieldUpdater(new FieldUpdater<AdminModel, String>() {
public void update(final int index, final AdminModel object, final String value) {
Window.alert(index + "-" + value);
}
});
After clicked on edit button , alert-box has appeared , but not on delete button. When I clicked on delete button , nothing has appeared. What would be the problem ?
Addition: How can I decide which button was clicked by user (edit or delete) from my presenter ?
I would really appreciate any of your suggestions because I am troubled on it for a long times. Thanks!
ButtonCell filters events on the first child element only: https://gwt.googlesource.com/gwt/+/2.6.1/user/src/com/google/gwt/cell/client/ButtonCell.java This is why you don't get an event when clicking the second button (note: the goal of that code is to make sure you clicked on the button, and not on blank space around the button; see https://gwt.googlesource.com/gwt/+/a0dc88c8be7408be9554f746eb1ec93798183a28)
The easiest way to implement a two-button cell is to use a CompositeCell; it requires that child cells are rendered into sibling elements though (uses <span>s by default, example below overrides the rendering to use <div>s so your buttons stack each on its own line).
new CompositeCell<AdminModel>(Arrays.asList(
// First button
new HasCell<AdminModel, String>() {
#Override public Cell<String> getCell() { return new ButtonCell(); }
#Override public FieldUpdated<AdminModel, String> getFieldUpdater() {
return new FieldUpdater<AdminModel, String>() {
#Override public void update(int index, AdminModel object, String value) {
Window.alert("Edit " + object.getId());
}
};
}
#Override public String getValue(AdminModel o) {
return "Edit";
}
},
// Second button
new HasCell<AdminModel, String>() {
#Override public Cell<String> getCell() { return new ButtonCell(); }
#Override public FieldUpdated<AdminModel, String> getFieldUpdater() {
return new FieldUpdater<AdminModel, String>() {
#Override public void update(int index, AdminModel object, String value) {
Window.alert("Delete " + object.getId());
}
};
}
#Override public String getValue(AdminModel o) {
return "Delete";
}
}) {
#Override protected <X> void render(Cell.Context context, AdminModel value, SafeHtmlBuilder sb, HasCell<String,X> hasCell) {
// use a <div> instead of the default <span>
Cell<X> cell = hasCell.getCell();
sb.appendHtmlConstant("<div>");
cell.render(context, hasCell.getValue(value), sb);
sb.appendHtmlConstant("</div>");
}
};
(note: in your case, because the button's text doesn't depend on the row object, maybe you should rather use an ActionCell; it would better fit "semantically" with what you're doing, but otherwise it's almost the same; with an ActionCell, you'd use HasCell<AdminModel, AdminModel>, ActionCell<AdminModel>, getFieldUpdater would return null, and thegetValueof theHasCellwould just return theAdminModel` argument as-is).
Otherwise, implement your Cell (or AbstractCell) entirely by yourself.
Ideally, a column should have only one type of cell be it ImageCell, ButtonCell etc. Because all this ImageCell and ButtonCell does not provide any in-built events. The events are handled by FieldUpdater itself which does not have differentiators to identify that which ButtonCell is clicked. Ideally on click of that column, the field-updater will be called.
You should rather create your own composite widget which extends HasCell. This composite widget will have two different buttons and those in built methods are called on click of respective button.
public void onModuleLoad() {
CellTable<Person> table = new CellTable<Person>();
List<HasCell<Person, ?>> cells = new LinkedList<HasCell<Person, ?>>();
cells.add(new ActionHasCell("Edit", new Delegate<Person>() {
#Override
public void execute(Person object) {
// EDIT CODE
}
}));
cells.add(new ActionHasCell("Delete", new Delegate<Person>() {
#Override
public void execute(Person object) {
// DELETE CODE
}
}));
CompositeCell<Person> cell = new CompositeCell<Person>(cells);
table.addColumn(new TextColumn<Person>() {
#Override
public String getValue(Person object) {
return object.getName()
}
}, "Name");
// ADD Cells for Age and Address
table.addColumn(new Column<Person, Person>(cell) {
#Override
public Person getValue(Person object) {
return object;
}
}, "Actions");
}
private class ActionHasCell implements HasCell<Person, Person> {
private ActionCell<Person> cell;
public ActionHasCell(String text, Delegate<Person> delegate) {
cell = new ActionCell<Person>(text, delegate);
}
#Override
public Cell<Person> getCell() {
return cell;
}
#Override
public FieldUpdater<Person, Person> getFieldUpdater() {
return null;
}
#Override
public Person getValue(Person object) {
return object;
}
}
Also, see the link below.
[GWT CellTable-Need to have two buttons in last single cell of each row
I have DataGrid where one on of the columns contains images. I used this code to generate the column.
Column<Job, String> expandHideColumn = new Column<Job, String>(
imageCell) {
#Override
public String getValue(Job object) {
return null;
}
#Override
public void render(Context context, Job Object, SafeHtmlBuilder sb) {
sb.appendHtmlConstant("<img src='images/expand.jpeg' style='cursor: pointer' />");
}
}
What I want is on clicking the image it has to change. For this I added a click handler on the ImageCell like this
ImageCell imageCell = new ImageCell() {
#Override
public Set<String> getConsumedEvents() {
Set<String> events = new HashSet<String>();
events.add("click");
return events;
}
};
In the onBrowserEvent method I wrote this
#Override
public void onBrowserEvent(Context context, Element element,
Job job, NativeEvent event) {
if (element.getFirstChildElement().isOrHasChild(
Element.as(event.getEventTarget()))) {
if (element.getFirstChildElement().getPropertyString("src")
.matches("(.*)expand.jpeg")) {
element.getFirstChildElement().setPropertyString("src",
"images/collapse.jpeg");
} else {
element.getFirstChildElement().setPropertyString("src",
"images/expand.jpeg");
}
}
}
I don't think this is a good approach to change images on click event. Is there a better solution?
You can use a column value for know the state of the column :
Column<Job, Boolean> expandHideColumn = new Column<Job, Boolean>(new ImageExpandCollapseCell()) {
#Override
public Boolean getValue(Job object) {
return object.isExpand(); //The object know the expand state ?
}
}
expandHideColumn.setValueUpdater(new FieldUpdater<Job, Boolean>() {
void update(int index, Job object, Boolean value) {
object.setExpand(value);
}
});
The ImageExpandCollapseCell look like this :
public class ImageExpandCollapseCell extends AbstractCell<Boolean> {
final String EXPAND = "images/expand.jpeg";
final String COLLAPSE = "images/collapse.jpeg";
interface Template extends SafeHtmlTemplates {
#Template("<div style=\"float:right\"><img src=\"" + url + "\"></div>")
SafeHtml img(String url);
}
private static Template template;
/**
* Construct a new ImageCell.
*/
public ImageCell() {
super("click"); //Replace your getConsumedEvents()
if (template == null) {
template = GWT.create(Template.class);
}
}
#Override
public void render(Context context, Boolean value, SafeHtmlBuilder sb) {
if (value != null) {
sb.append(template.img(UriUtils.fromSafeConstant(value ? EXPAND : COLLAPSE)));
}
}
#Override
public void onBrowserEvent(Context context, Element element,
Boolean value, NativeEvent event, ValueUpdater<Boolean> valueUpdater) {
valueUpdate.update(!value);
}
}
I improve the proposed version of user905374
It's not a good idea to instantiate new value in the render method.
The column render method call the Cell render method, you musn't replace it !
With the FieldUpdater, you can change the state of the image : expand or collapse and update the cell display (it will be rendered again).
I have set up an AsyncDataProvider for my CellTable and added it to a SimplePager. I have hooked up a ListHandler to take care of sorting based on a column.
When I click the header of that column, the data doesn't change but on going to the next/previous page within the pager the data is then sorted. Also before the column is clicked there is no visual indicator on the column that would indicate that it is meant to be sortable.
How can I get the data to update when I click the header of the Column?
Here's my code snippet
service.getHosts(environment, new AsyncCallback<Set<String>>() {
#Override
public void onSuccess(final Set<String> hosts) {
final List<String> hostList = new ArrayList<String>(hosts);
//Populate the table
CellTable<String> hostTable = new CellTable<String>();
TextColumn<String> hostNameColumn = new TextColumn<String>(){
#Override
public String getValue(String string){
return string;
}
};
NumberCell numberCell = new NumberCell();
Column<String, Number> lengthColumn = new Column<String, Number>(numberCell){
#Override
public Number getValue(String string) {
return new Integer(string.length());
}
};
AsyncDataProvider<String> dataProvider = new AsyncDataProvider<String>() {
#Override
protected void onRangeChanged(HasData<String> data) {
int start = data.getVisibleRange().getStart();
int end = start + data.getVisibleRange().getLength();
List<String> subList = hostList.subList(start, end);
updateRowData(start, subList);
}
};
// Hooking up sorting
ListHandler<String> columnSortHandler = new ListHandler<String>(hostList);
columnSortHandler.setComparator(lengthColumn, new Comparator<String>(){
#Override
public int compare(String arg0, String arg1) {
return new Integer(arg0.length()).compareTo(arg1.length());
}
});
hostTable.setPageSize(10);
hostTable.addColumnSortHandler(columnSortHandler);
hostTable.addColumn(hostNameColumn,"Host Name");
lengthColumn.setSortable(true);
hostTable.addColumn(lengthColumn, "Length");
VerticalPanel verticalPanel = new VerticalPanel();
SimplePager pager = new SimplePager();
pager.setDisplay(hostTable);
dataProvider.addDataDisplay(hostTable);
dataProvider.updateRowCount(hosts.size(), true);
verticalPanel.add(hostTable);
verticalPanel.add(pager);
RootPanel.get().add(verticalPanel);
}
#Override
public void onFailure(Throwable throwable) {
Window.alert(throwable.getMessage());
}
});
I'm not sure how to make sure that the list is shared by both the table and the Pager. Before adding the pager I was using
ListDataProvider<String> dataProvider = new ListDataProvider<String>();
ListHandler<String> columnSortHandler = new ListHandler<String>(dataProvider.getList());
The AsyncDataProvider doesn't have the method getList.
To summarize I want the data to be sorted as soon as the column is clicked and not after I move forward/backward with the pager controls.
As per the suggestion I have changed the code for the AsyncDataProvider to
AsyncDataProvider<String> dataProvider = new AsyncDataProvider<String>() {
#Override
protected void onRangeChanged(HasData<String> data) {
int start = data.getVisibleRange().getStart();
int end = start + data.getVisibleRange().getLength();
List<String> subList = hostList.subList(start, end);
// Hooking up sorting
ListHandler<String> columnSortHandler = new ListHandler<String>(hostList);
hostTable.addColumnSortHandler(columnSortHandler);
columnSortHandler.setComparator(lengthColumn, new Comparator<String>(){
#Override
public int compare(String v0, String v1) {
return new Integer(v0.length).compareTo(v1.length);
}
});
updateRowData(start, subList);
}
};
But there is no change in the behavior even after that. Can someone please explain the process. The GWT showcase app seems to have this functionality but how they've done it isn't all that clear.
When using an AsyncDataProvider both pagination and sorting are meant to be done on the server side. You will need an AsyncHandler to go with your AsyncDataProvider:
AsyncHandler columnSortHandler = new AsyncHandler(dataGrid) {
#Override
public void onColumnSort(ColumnSortEvent event) {
#SuppressWarnings("unchecked")
int sortIndex = dataGrid.getColumnIndex((Column<Entry, ?>) event.getColumn());
boolean isAscending = event.isSortAscending();
service.getPage(0, sortIndex, isAscending, new AsyncCallback<List<Entry>>() {
public void onFailure(Throwable caught) {
}
public void onSuccess(List<Entry> result) {
pager.setPage(0);
provider.updateRowData(0, result);
}
});
}
};
dataGrid.addColumnSortHandler(columnSortHandler);
Clicking on a column header will then fire a columnSortEvent. Then you have to get the column clicked. I am overloading my servlet to provide both sorting and pagination, so I pass a -1 for the column index when only pagination is desired.
provider = new AsyncDataProvider<Entry>() {
#Override
protected void onRangeChanged(HasData<Entry> display) {
final int start = display.getVisibleRange().getStart();
service.getPage(start, -1, true, new AsyncCallback<List<Entry>>() {
#Override
public void onFailure(Throwable caught) {
}
#Override
public void onSuccess(List<Entry> result) {
provider.updateRowData(start, result);
}
});
}
};
provider.addDataDisplay(dataGrid);
provider.updateRowCount(0, true);
Then your servlet implementation of getPage performs the sorting and pagination. The whole thing is much easier to follow with separate event handlers.
I think the problem is with the ListHandler initialization. You are passing hostList as a parameter to List Handler and in onRangeChange method you are calling updateRowData with a different list (sublist).
Make sure you use the same list in both the places.
or
Move your ListHander initialization and cellTable.addColumnSortHandler method call to onRangeChange method after updateRowData call.
am using GWT 2.4, Hibernate and MysQL
I created a cell table , when i click on a cell i want to display the data/value in that particular cell
Thanks in advance
#override
public Widget onInitialize(){
CellTable grid = new CellTable<Bean>();
grid.setWidth("100%",true);
setColumns(grid);
}
private void setColumns(CellTable grid){
Column<Bean, String> firstNameColumn = new Column<Bean, String>(
new EditTextCell()) {
#Override
public String getValue(Bean object) {
return object.getFirstName();
}
};
firstNameColumn.setSortable(true);
grid.addColumn(firstNameColumn, "First Name");
Column<Bean, String> imageColumn = new Column<Bean, String>(
new ClikableTextCell()) {
#Override
public String getValue(Bean object) {
return "clickhere";
}
};
imageColumn.setSortable(true);
grid.addColumn(imageColumn, "Add Information");
firstNameColumn.setFieldUpdater(new FieldUpdater<Bean, String>() {
public void update(int index, Bean object, String value) {
Window.alert("You clicked " + object.getFullName());
}
});
cellTable.setColumnWidth(firstNameColumn, 20, Unit.PCT);
}
Use DataProvider and SingleSelectionModel for you cellTable:
private final ListDataProvider<SomeClass> dataProvider = new ListDataProvider<SomeClass>();
private final SingleSelectionModel<SomeClass> selectionModel = new SingleSelectionModel<SomeClass>();
//then
table.setSelectionModel(selectionModel);
dataProvider.addDataDisplay(table);
Heres how u can get the selected objects info:
showDataValueOfCellBtn.addClickHandler(new ClickHandler() {
#Override
public void onClick(ClickEvent event) {
SomeClass selected = selectionModel.getSelectedObject();
Window.alert (selected.getValue());
}
});
I have tried this but didn't work
Column<ContactInfo, String> imageColumn = new Column<ContactInfo, String>(new ImageCell()) {
#Override
public String getValue(ContactInfo object) {
return "contact.jpg";
}
};
imageColumn.setFieldUpdater(new FieldUpdater<ContactInfo, String>() {
#Override
public void update(int index, ContactInfo object, String value) {
Window.alert("You clicked " + object.firstName);
}
});
cellTable.addColumn(imageColumn, SafeHtmlUtils.fromSafeConstant("<br/>"));
public class ButtonImageCell extends ButtonCell{
#Override
public void render(com.google.gwt.cell.client.Cell.Context context,
String value, SafeHtmlBuilder sb) {
SafeHtml html = SafeHtmlUtils.fromTrustedString(new Image(value).toString());
sb.append(html);
}
}
in use:
final Column<ReportDTOProxy, String> buttonImageCellTest = new Column<ProxyObject, String>(new ButtonImageCell()) {
#Override
public String getValue(ProxyObject row) {
//url to image
return row.getImageUrl();
}
};
You can extend ImageCell class and override 2 it's methods - getConsumedEvents and onBrowserEvent. Example:
private class MyImageCell extends ImageCell{
#Override
public Set<String> getConsumedEvents() {
Set<String> consumedEvents = new HashSet<String>();
consumedEvents.add("dblclick");
return consumedEvents;
}
#Override
public void onBrowserEvent(Context context, Element parent,
String value, NativeEvent event,
ValueUpdater<String> valueUpdater) {
switch (DOM.eventGetType((Event)event)) {
case Event.ONDBLCLICK:
// TODO
break;
default:
break;
}
}
}
I did something similar mixing a Button cell with the renderer from an ImageCell....
ButtonCell bc = new ButtonCell() {
#Override
public void render(Context context, SafeHtml data, SafeHtmlBuilder sb) {
if (data != null) {
ImageResource icon = Icons.BUNDLE.pieChart();
SafeHtml html = SafeHtmlUtils.fromTrustedString(AbstractImagePrototype.create(icon).getHTML());
sb.append(html);
}
}
};
You get the idea. The only problem is that it does not display the "hand" icon when you hover over it.... likely it can be fixed by setting the CSS.
You can try this rather than using ButtonCell or ImageCell. This will work for sure. As I have implemented for my requirement. Let me know how does it goes..
ClickableTextCell imageCell = new ClickableTextCell() {
#Override
public void render(Context context, SafeHtml data, SafeHtmlBuilder sb) {
if (data != null) {
String imagePath = "icon.png";
sb.append(imagePath);
}
}
};
Column<ContactInfo, String> imageColumn = new Column<ContactInfo, String>(imageCell) {
#Override
public String getValue(ContactInfo object) {
return "";
}
};
imageColumn.setFieldUpdater(new FieldUpdater<ContactInfo, String>() {
#Override
public void update(int index, ContactInfo object, String value) {
Window.alert("You clicked " + object.firstName);
}
});
cellTable.addColumn(imageColumn, SafeHtmlUtils.fromSafeConstant("<br/>"));
A good solution for this issue, if you use ActionCell that is able to handle clicking. The use of it is a bit complicatied, but for me it worked pretty well.
First you need to initialize ActionCell with a delegate, in the constructor, write new ActionCell.Delegate<your class>. In this override the method execute and in that write your code that handle the clicking event.
The other thing you need to do is building up a html from the image. The SafeHtmlUtils class gives you a very easy way to do that. It's fromTrustedString method helps you building up the html:
SafeHtmlUtils.fromTrustedString(AbstractImagePrototype.create ("Your image from a resource class").getHTML());
This way the SafeHtml field can be initalized and if you give the ActionCell's contructor the SafeHtml and the Delegate, that it will do the work for you.
In this example a button will be initialized with the image from the bundle file in it. You can make it without the button if you override the render method of the ActionCell and append the SafeHtmlBuilder in the method with the same SafeHtml variable as above.
My code looks like the following:
IdentityColumn<Type> imageCell = new IdentityColumn<Type>(new ActionCell<Type>("AnyString",
new ActionCell.Delegate<Type>() {
#Override
public void execute(final Type item) {
"your code"
}
}) {
#Override
public void render(Context context, Type value, SafeHtmlBuilder sb) {
if (value != null) {
SafeHtml html = SafeHtmlUtils.fromTrustedString(AbstractImagePrototype.create(resource.image).getHTML());
sb.append(html);
}
}
});
You'd rather override the method in an another class but I didn't want to split them for this post. It worked for me very well, I hope it will help other's too.
I got all the above and added them in my app. Thanks to all. stackoverflow rocks!
ButtonCell bc = new ButtonCell() {
#Override
public void render(Context context, SafeHtml data, SafeHtmlBuilder sb) {
if (data != null) {
ImageResource icon = Connector.imageResources.minus();
Image image = new Image(icon);
//fix the mouse pointer
image.getElement().getStyle().setCursor(Cursor.POINTER);
//Do something with the DATA
image.setTitle("Delete " + data.asString());
SafeHtml html = SafeHtmlUtils.fromTrustedString(image.toString());
sb.append(html);
}
}
};
Column<InstanceProperty, String> imageColumn = new Column<InstanceProperty, String>(bc) {
#Override
public String getValue(InstanceProperty object) {
//return the DATA
return object.getKey();
}
};
imageColumn.setFieldUpdater(new FieldUpdater<InstanceProperty, String>() {
#Override
public void update(int index, InstanceProperty property,
String value) {
//you can also use the DATA to do something
InstancePropertiesTable.this.dataProvider.getList().remove(index);
}
});
addColumn(imageColumn, "");
This worked for me:
public class ButtonImageCell extends ButtonCell{
#Override
public void render(com.google.gwt.cell.client.Cell.Context context,
String renderedHtmlStr, SafeHtmlBuilder sb) {
sb.appendHtmlConstant(renderedHtmlStr);
}
}
In a class containing CellTable table:
TableResources resources = GWT.create(TableResources.class);
ImageResourceRenderer imageRenderer = new ImageResourceRenderer();
...
Column<MyRecord, String> buttonCol = new Column<MyRecord, String>(new ButtonImageCell()) {
#Override
public String getValue(MyRecord record) {
if(record.isOn())
return imageRenderer.render(resources.getOnImg()).asString();
else
return imageRenderer.render(resources.getOffImg()).asString();
}
};
buttonCol.setFieldUpdater(new FieldUpdater<MyRecord, String>() {
public void update(int index, MyRecordobject, String value) {
if (Window.confirm("Do stuff?")) {
//todo: stuff
}
}
});
...
table.addColumn(buttonCol, "");
Where the ImageResource comes from (resources):
public interface TableResources extends CellTable.Resources {
interface TableStyle extends CellTable.Style {
}
#Source("/images/on.png")
ImageResource getOnImg();
#Source("/images/off.png")
ImageResource getOffImg();
}
You need to sinkEvents() with appropriate bits.
Refer to answer of Question Adding ClickHandler to div which contains many other widget.