I am trying to construct a DataGrid in GWT that will show an arbitrary dataset taken from an rpc method.
I have done some progress as I get the fields from a method and the data from another.
I have managed to construct the Datagrid and add the columns from the rpc.getFields() method and fill the table using an AsyncDataProvider.
The problem is that when I refresh the browser, it duplicates all the columns at the Datagrid. I cannot figure out what to do. I tried to remove first all the columns but no luck.
I attach the code if anyone have an idea.
public class MyCallBack implements AsyncCallback<List<Field>> {
DataGrid<Record> dg;
public MyCallBack(DataGrid<Record> dgrid) {
this.dg=dgrid;
}
public void onFailure(Throwable caught) {
Window.alert(caught.getMessage());
}
public void onSuccess(List<Field> result) {
for (int i=0;i<=result.size();i++) {
IndexedColumn ic = new IndexedColumn(i);
dg.addColumn(ic, result.get(i).getLabel());
}
}
public AsyncCallback<List<Field>> getCb() {
return this;
}
public void onModuleLoad() {
final DataGrid<Record> dg = new DataGrid<Record>();
MyCallBack mcb = new MyCallBack(dg);
DataProvider dp = new DataProvider();
DBConnectionAsync rpcService = (DBConnectionAsync) GWT.create(DBConnection.class);
ServiceDefTarget target = (ServiceDefTarget) rpcService;
String moduleRelativeURL = GWT.getModuleBaseURL() + "MySQLConnection";
target.setServiceEntryPoint(moduleRelativeURL);
rpcService.getFields(mcb.getCb());
dp.addDataDisplay(dg);
dg.setVisibleRange(0, 200);
SplitLayoutPanel slp = new SplitLayoutPanel();
slp.setHeight("700px");
slp.setWidth("1500px");
slp.addWest(dg, 770);
RootPanel.get().add(slp);
}
When you refresh a browser, all UI is lost. There is no difference between (a) show the UI for the first time or (b) show the UI after browser refresh.
Your comment "Only if I restart tomcat it works" suggests that the problem is on the server side. Most likely, you return twice the number of data points on a second call.
Try clearing the table before filling it like this:
public void onSuccess(List<Field> result) {
clearTable();
for (int i=0;i<=result.size();i++) {
IndexedColumn ic = new IndexedColumn(i);
dg.addColumn(ic, result.get(i).getLabel());
}
}
private void clearTable(){
while (dg.getColumnCount() > 0) {
db.removeColumn(0);
}
}
Related
I want to implement a row deletion logic in a Nebula Nattable.
This is what I plan to do:
Add context menu to the Nattable which is described in http://blog.vogella.com/2015/02/03/nattable-context-menus-with-eclipse-menus/
Add an SWT Action to the menu which will implement the delete
my question is, which is the best way to accomplish this:
Should I delete the corresponding value from my data model and the table view is refreshed when I execute this.natview.refresh();?
OR
Should I get the rows from SelectionLayer and delete them (if so how do I do ?)?
OR
is there any default support for this function through IConfiguration?
In NatTable you would typically do the following:
Create a command for deleting a row
public class DeleteRowCommand extends AbstractRowCommand {
public DeleteRowCommand(ILayer layer, int rowPosition) {
super(layer, rowPosition);
}
protected DeleteRowCommand(DeleteRowCommand command) {
super(command);
}
#Override
public ILayerCommand cloneCommand() {
return new DeleteRowCommand(this);
}
}
Create a command handler for that command
public class DeleteRowCommandHandler<T> implements ILayerCommandHandler<DeleteRowCommand> {
private List<T> bodyData;
public DeleteRowCommandHandler(List<T> bodyData) {
this.bodyData = bodyData;
}
#Override
public Class<DeleteRowCommand> getCommandClass() {
return DeleteRowCommand.class;
}
#Override
public boolean doCommand(ILayer targetLayer, DeleteRowCommand command) {
//convert the transported position to the target layer
if (command.convertToTargetLayer(targetLayer)) {
//remove the element
this.bodyData.remove(command.getRowPosition());
//fire the event to refresh
targetLayer.fireLayerEvent(new RowDeleteEvent(targetLayer, command.getRowPosition()));
return true;
}
return false;
}
}
Register the command handler to the body DataLayer
bodyDataLayer.registerCommandHandler(
new DeleteRowCommandHandler<your type>(bodyDataProvider.getList()));
Add a menu item to your menu configuration that fires the command
new PopupMenuBuilder(natTable)
.withMenuItemProvider(new IMenuItemProvider() {
#Override
public void addMenuItem(NatTable natTable, Menu popupMenu) {
MenuItem deleteRow = new MenuItem(popupMenu, SWT.PUSH);
deleteRow.setText("Delete");
deleteRow.setEnabled(true);
deleteRow.addSelectionListener(new SelectionAdapter() {
#Override
public void widgetSelected(SelectionEvent event) {
int rowPosition = MenuItemProviders.getNatEventData(event).getRowPosition();
natTable.doCommand(new DeleteRowCommand(natTable, rowPosition));
}
});
}
})
.build();
Using this you don't need to call NatTable#refresh() because the command handler fires a RowDeleteEvent. I also don't suggest to call NatTable#refresh() in such a case, as it might change and refresh more than it should and would not update other states correctly, which is done correctly by firing the RowDeleteEvent.
Note that the shown example deletes the row for which the context menu is opened. If all selected rows should be deleted, you should create a command handler that knows the SelectionLayer and retrieve the selected rows as shown in the other answer.
In our application we do the following:
Get selected row objects:
SelectionLayer selectionLayer = body.getSelectionLayer();
int[] selectedRowPositions = selectionLayer.getFullySelectedRowPositions();
Vector<Your Model Objects> rowObjectsToRemove = new Vector<Your Model Objects>();
for (int rowPosition : selectedRowPositions) {
int rowIndex = selectionLayer.getRowIndexByPosition(rowPosition);
rowObjectsToRemove .add(listDataProvider.getRowObject(rowIndex));
}
Remove them from the data provider
call natTable.refresh()
I have a GWT Cell Tree that I use to display a file structure from a CMS. I am using a AsyncDataProvider that loads data from a custom RPC class I created. I also have a Web Socket system that will broadcast events (File create, renamed, moved, deleted etc) from other clients also working in the system.
What I am trying to wrap my head around is when I recieve one of these events, how I correctly update my Cell Tree?
I suppose this problem would be analogus to having two instances of my Cell Tree on the page, which are presenting the same server-side data and wanting to ensure that when the user updated one, that the other updated as well, via using the EventBus.
I feel this should be pretty simple but I have spent about 6 hours on it now with no headway. My code is included below:
NOTE: I am not using RequestFactory even though it may look like I am it is my custom RPC framework. Also, FileEntity is just a simple representation of a file which has a name accessible by getName().
private void drawTree() {
// fileService is injected earlier on and is my own custom rpc service
TreeViewModel model = new CustomTreeModel(new FileDataProvider(fileService));
CellTree tree = new CellTree(model, "Root");
tree.setAnimationEnabled(true);
getView().getWorkspace().add(tree);
}
private static class CustomTreeModel implements TreeViewModel {
// I am trying to use a single AsyncDataProvider so I have a single point of loading data which I can manipulate (Not sure if this is the correct way to go)
public CustomTreeModel(FileDataProvider dataProvider) {
this.provider = provider;
}
public <T> NodeInfo<?> getNodeInfo(final T value) {
if (!(value instanceof FileEntity)) {
// I already have the root File loaded in my presenter, if we are at the root of the tree, I just add it via a list here
ListDataProvider<FileEntity> dataProvider = new ListDataProvider<FileEntity>();
dataProvider.getList().add(TreeWorkspacePresenter.rootFolder);
return new DefaultNodeInfo<FileEntity>(dataProvider,
new FileCell());
} else {
// Otherwise I know that we are loading some tree child data, and I invoke the AsyncProvider to load it from the server
provider.setFocusFile(value);
return new DefaultNodeInfo<FileEntity>(provider,
new FileCell());
}
}
public boolean isLeaf(Object value) {
if(value == null || value instanceof Folder)
return false;
return true;
}
}
public class FileDataProvider extends AsyncDataProvider<FileEntity> {
private FileEntity focusFile;
private FileService service;
#Inject
public FileDataProvider(FileService service){
this.service = service;
}
public void setFocusFile(FileEntity focusFile){
this.focusFile = focusFile;
}
#Override
protected void onRangeChanged(HasData<FileEntity> display) {
service.getChildren(((Folder) focusFile),
new Reciever<List<FileEntity>>() {
#Override
public void onSuccess(List<FileEntity> files) {
updateRowData(0, files);
}
#Override
public void onFailure(Throwable error) {
Window.alert(error.toString());
}
});
}
}
/**
* The cell used to render Files.
*/
public static class FileCell extends AbstractCell<FileEntity> {
private FileEntity file;
public FileEntity getFile() {
return file;
}
#Override
public void render(Context context, FileEntity file, SafeHtmlBuilder sb) {
if (file != null) {
this.file = file;
sb.appendEscaped(file.getName());
}
}
}
Currently there is no direct support for individual tree item refresh even in the latest gwt version.
But there is a workaround for this. Each tree item is associated with an value. Using this value you can get the corresponding tree item.
In your case, i assume, you know which item to update/refresh ie you know which File Entity has changed. Use this file entity to search for the corresponding tree item. Once you get the tree item you just need to expand and collapse or collapse and expand its parent item. This makes parent item to re-render its children. Your changed file entity is one among the children. So it get refreshed.
public void refreshFileEntity(FileEntity fileEntity)
{
TreeNode fileEntityNode = getFileEntityNode(fileEntity, cellTree.getRootTreeNode()
// For expnad and collapse run this for loop
for ( int i = 0; i < fileEntityNode.getParent().getChildCount(); i++ )
{
if ( !fileEntityNode.getParent().isChildLeaf( i ) )
{
fileEntityNode.getParent().setChildOpen( i, true );
}
}
}
public TreeNode getFileEntityNode(FileEntity fileEntity, TreeNode treeNode)
{
if(treeNode.getChildren == null)
{
return null;
}
for(TreeNode node : treeNode.getChildren())
{
if(fileEntity.getId().equals( node.getValue.getId() ))
{
return node;
}
getEntityNode(fileEntity, node);
}
}
You can use the dataprovider to update the celltree.
You can update the complete cell tree with:
provider.setList(pList);
provider.refresh();
If you want to update only a special cell you can get the listwrapper from the dataprovider and only set one element.
provider.getList().set(12, element);
I am Trying to create Eclipse Plugin which has a composite with two TreeViewer side by side. On click of each TreeViewer content Eclipse property view should give appropriate information. Now I wanted to set Selection provider for both of this treeviewer hence I used
setSelectionProvider(treeViewer1)
setSelectionProvider(treeviewer2)
But only the second added treeviewer get set since the first one is overwritten. I am intiating this two treeviewer from class Queue.java. Hence I implemented the interface ISelectionProvider over Queue.java as below:
public void addSelectionChangedListener(ISelectionChangedListener listener)
{
selectionChangedListeners.add(listener);
}
public void
removeSelectionChangedListener(ISelectionChangedListener listener)
{
selectionChangedListeners.remove(listener);
}
private void fireSelectionChanged(final SelectionChangedEvent event)
{
Object[] listeners = selectionChangedListeners.getListeners();
for (int i = 0; i < listeners.length; ++i)
{
final ISelectionChangedListener l =
(ISelectionChangedListener) listeners[i];
Platform.run(new SafeRunnable()
{
public void run()
{
l.selectionChanged(event);
}
#Override
public void handleException(Throwable e)
{
removeSelectionChangedListener(l);
}
});
}
}
public void setSelection(ISelection selection)
{
fireSelectionChanged(new SelectionChangedEvent(this, selection));
}
public ISelection getSelection()
{
ArrayList<Object> list = new ArrayList<Object>();
Object o = getProperties();
if (o instanceof IPropertySource)
list.add(o);
return new StructuredSelection(list);
}
Can anyone help me how to resolve this issue. I will be grateful. thanks in advance. Tor.
Your view would have to write a selection provider wrapper or mediator that would delegate to the viewer that currently had focus. Then your view would set it up something like this:
SelectionProviderWrapper wrapper = new SelectionProviderWrapper();
wrapper.addViewer(treeViewer1);
wrapper.addViewer(treeViewer2);
getSite().setSelectionProvider(wrapper);
I would check out org.eclipse.jdt.internal.ui.viewsupport.SelectionProviderMediator for an example of a selection provider for multiple JFace viewers.
I am just creating a new Proxy:
LayoutExampleRequest r = requestFactory.employeeRequest();
DepartmentProxy d = r.create(DepartmentProxy.class);
r.save(d);
departmentEditor.editProxy(d, r);
Then pass the Proxy and the Request(LayoutExampleRequest ) to my editor
driver.edit(proxy, request);
Until here ! everything works as espected. I can save Department objects with null EmployeeProxy. Now iam getting with a suggest box Proxys of EmployeeProxy from the server.
search = new SuggestBox(new SuggestOracle() {
#Override
public void requestSuggestions(final Request request,final Callback callback) {
System.out.println(request.getQuery());
//ignore less than 3
if(request.getQuery().length() > 3){
requestFactory.employeeRequest().search(request.getQuery()).fire(new Receiver<List<EmployeeProxy>>(){
#Override
public void onSuccess(List<EmployeeProxy> response) {
List<MySuggestion<EmployeeProxy>> suggestions = new ArrayList<MySuggestion<EmployeeProxy>>();
for(EmployeeProxy e:response){
MySuggestion<EmployeeProxy> suggestion = new MySuggestion<EmployeeProxy>();
suggestion.setModel(e,e.getFirstName(),e.getFirstName()+" "+e.getLastName());
suggestions.add(suggestion);
}
callback.onSuggestionsReady(request, new Response(suggestions));
}
});
}
}
});
MySuggestion is a wrapper class to handle the EmployeeProxy.
Now i want to add this EmployeeProxy to my DeparmentProxy since i have a #OneToOne on JPA.
search.addSelectionHandler(new SelectionHandler<SuggestOracle.Suggestion>() {
#Override
public void onSelection(SelectionEvent<Suggestion> event) {
MySuggestion<EmployeeProxy> s = (MySuggestion<EmployeeProxy>)event.getSelectedItem();
proxy.setSupervisor(s.getModel());
}
});
proxy is the EntityProxy for Department (I sent to my editor) driver.edit(proxy, request);
then i fire the driver:
departmentEditor.getDriver().flush().fire(new Receiver<Void>() {
#Override
public void onSuccess(Void response) {
Window.alert("Success");
// refresh the datagrid
Range range = dataGrid.getVisibleRange();
dataGrid.setVisibleRangeAndClearData(range, true); //1st way
// create a new DepartmentProxy to bind to the Editor.
createProxy();
// change button text
updateButton.setText("Save");
}
#Override
public void onConstraintViolation(Set<ConstraintViolation<?>> violations) {
for(ConstraintViolation v :violations){
Window.alert(v.getMessage()+" "+v.getPropertyPath());
}
}
#Override
public void onFailure(ServerFailure error) {
Window.alert(error.getMessage());
}
});
The problem is iam getting ConstraintViolations from the EmployeeProxy, is like the driver atach the EmployeeProxy but with null values.
(Iam validating my Entityes with JSR-330 )
Dont know how to make a relationship with a new Proxy with other taked from the server. in a #OneToOne relationship
Any help would be nice!
Thank you
/* UPDATE */
Something like this but with editor
final LayoutExampleRequest r = requestFactory.employeeRequest();
final DepartmentProxy d = r.create(DepartmentProxy.class);
d.setName("Name");
d.setService(Service.CONTRACT_MANAGMENT);
// get some random employee
requestFactory.employeeRequest().findById(1).fire(new Receiver<EmployeeProxy>() {
#Override
public void onSuccess(EmployeeProxy response) {
d.setSupervisor(response);
r.save(d).fire(new Receiver<DepartmentProxy>() {
#Override
public void onSuccess(DepartmentProxy response) {
Window.alert("Kidding me! why editor cant get it work =p?");
}
});
}
});
The problem was i put on my editor properties of the EmployeeProxy so when a user select the employeproxy would see information about it, so i delete them and then do the same and now works.
Is like GWT when detects properties from another proxy on the editor thinks you will fill it. And the line:
proxy.setSupervisor(s.getModel());
doesn't works.
Assuming that data retrieves from DataStore using RPCproxy, populate to grid using ListStore upon opening the page.
Then, there's a form to add an entity and after modification it will reflect the new list in GXT grid with the new added row.
How can reload the grid? I tried .reconfigure() method in Grid but didn't work.
grid.getStore().getLoader().load();
update:
First of all you must extract Grid before your Proxy, and the second thing is to change your RPC callback:
public class PagingBeanModelGridExample extends LayoutContainer {
//put grid Class outside a method or declare it as a final on the begin of a method
Grid grid = null;
protected void onRender(Element parent, int index) {
super.onRender(parent, index);
RpcProxy> proxy = new RpcProxy>() {
#Override
public void load(Object loadConfig, final AsyncCallback> callback) {
//modification here - look that callback is overriden not passed through!!
service.getBeanPosts((PagingLoadConfig) loadConfig, new AsyncCallback>() {
public void onFailure(Throwable caught) {
callback.onFailure(caught);
}
public void onSuccess(PagingLoadResult result) {
callback.onSuccess(result);
//here you are reloading store
grid.getStore().getLoader().load();
}
});
}
};
// loader
final BasePagingLoader> loader = new BasePagingLoader>(proxy, new BeanModelReader());
ListStore store = new ListStore(loader);
List columns = new ArrayList();
//...
ColumnModel cm = new ColumnModel(columns);
grid = new Grid(store, cm);
add(grid);
}
}
To display the new data to grid do you really need to reload the grid?
You can create a new model object with the new data and add this to the ListStore.
Suppose you have a CommentModel which extends the BaseModel and a ListStore of Comment model commentStore.
final ListStore<Commentmodel> commentStore = new ListStore<Commentmodel>();
//now call a rpc to load all available comments and add this to the commentStore.
commentService.getAllComment(new AsyncCallback<List<Commentmodel>>() {
#Override
public void onFailure(Throwable caught) {
lbError.setText("data loading failure");
}
#Override
public void onSuccess(List<Commentmodel> result) {
commentStore.add(result);
}
});
commentService is an AsyncService.
Now if a user post a comment, just create a new CommentModel object with the new data
CommentModel newData = new CommentModel('user name', 'message','date');
And add this to the commentStore.
commentStore.add(newData);
Hope this will serve you purpose.
But if you really need to reload the whole set of data, call the service again. In the onSuccess method first clear the commentStore then add result. Remember this is more more time consuming that the 1st approach.