GWT CEll Browser Real Time Update - gwt

Question

has someone been able to correctly to update a cell browser at runtime, i.e. when u remove a node or add a node, the change is reflected immediately in the CEll Browser, because I am using a List and when i am making a change it is not being updated on the spot

Answer 1

You can use ListDataProvider setList(...) method for dynamic updates. Here is an example how I update cell browser via RPC:
private void loadAllData(final ListDataProvider<Data> dataProvider) {
dBservice.getAllData(new AsyncCallback<List<Data>>() {
public void onSuccess(List<Data> result) {
dataProvider.setList(result);
}
public void onFailure(Throwable caught) {
caught.printStackTrace();
}
});
}

Answer 2

to refresh a cellBrowser you have to close all the child on the root node.
anyway something like this
for (int i = 0; i < cellBrowser.getRootTreeNode().getChildCount(); i++) {
cellBrowser.getRootTreeNode().setChildOpen(i, false);
}
the AsyncDataProvider calls refreshes data
private final class Model implements TreeViewModel{
private List<ZonaProxy> zonaList = null;
private List<CategoriaProxy> categoriaList = null;
public void setCategoriaList(List<CategoriaProxy> categoriaList) {
this.categoriaList = categoriaList;
}
public void setListZona(List<ZonaProxy> zonaList) {
this.zonaList = zonaList;
}
#SuppressWarnings({ "unchecked", "rawtypes" })
public <T> NodeInfo<?> getNodeInfo(T value) {
CategoryDataProvider dataProvider1 = new CategoryDataProvider();
return new DefaultNodeInfo(dataProvider1, new CategoriaCell());
}
/**
* Check if the specified value represents a leaf node. Leaf nodes cannot be
* opened.
*/
public boolean isLeaf(Object value) {
if (value instanceof CategoriaProxy){
if (((CategoriaProxy) value).getLivello() == 3) {
return true;
}
}
return false;
}
}
private class CategoryDataProvider extends AsyncDataProvider<CategoriaProxy>
{
#Override
protected void onRangeChanged(HasData<CategoriaProxy> display)
{
requests.categoriaRequest().findAllCategorias(0, 8).with().fire(new Receiver<List<CategoriaProxy>>() {
#Override
public void onSuccess(List<CategoriaProxy> values) {
updateRowCount(values.size(), true);
updateRowData(0, values);
}
});
}
}
it Works.

Answer 3

Apparently it is not enough to change the data provider and refresh it.
You need also to force the affected cell to close and reopen it, as in this example
public void updateCellBrowser(String id) {
TreeNode node = getNode(cellBrowser.getRootTreeNode(),id);
if(node != null && ! node.isDestroyed()) {
TreeNode parent = node.getParent();
int index = node.getIndex();
parent.setChildOpen(index, false,true);
parent.setChildOpen(index, true, true);
}
}
In my particular example the cell ids are pathnames hence the following
implementation of getNode().
private TreeNode getNode(TreeNode node, String id) {
for(int i=0; i < node.getChildCount(); i++)
if(node.isChildOpen(i)) {
Object value = node.getChildValue(i);
if(value instanceof String) {
String nodeId = ((String) value);
if(id.equals(nodeId))
return node.setChildOpen(i, true);
if(id.startsWith(nodeId))
getNode(node.setChildOpen(i, true),id);
}
}
return null;
}