package org.jboss.as.console.client.widgets.tables;
import com.google.gwt.core.client.Scheduler;
import com.google.gwt.event.dom.client.KeyUpEvent;
import com.google.gwt.event.dom.client.KeyUpHandler;
import com.google.gwt.user.client.ui.HorizontalPanel;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.TextBox;
import com.google.gwt.user.client.ui.Widget;
import com.google.gwt.view.client.HasData;
import com.google.gwt.view.client.ListDataProvider;
import com.google.gwt.view.client.SelectionChangeEvent;
import com.google.gwt.view.client.SelectionModel;
import com.google.gwt.view.client.SingleSelectionModel;
import java.util.ArrayList;
import java.util.List;
/**
* <b>Caveat</b>: You need to provide set the data provider list before creating the filter instance.
*
* @author Heiko Braun
* @date 7/31/12
*/
public class DataProviderFilter<T> {
private ListDataProvider<T> delegate;
private ArrayList<T> origValues = new ArrayList<T>();
private Predicate predicate;
private TextBox filter;
public interface Predicate<T> {
boolean apply(String prefix, T candiate);
}
/**
* initialized the filter by calling {@link #snapshot()}
* @param delegate
* @param predicate
*/
public DataProviderFilter(ListDataProvider<T> delegate, Predicate<T> predicate) {
this.delegate = delegate;
this.predicate = predicate;
this.filter = new TextBox();
snapshot();
}
private void clearSelection() {
for(HasData<T> table : delegate.getDataDisplays())
{
SelectionModel<? super T> selectionModel = table.getSelectionModel();
if(selectionModel instanceof SingleSelectionModel)
{
SingleSelectionModel<T> sm = (SingleSelectionModel<T>)selectionModel;
T selectedObject = sm.getSelectedObject();
if(selectedObject!=null)
((SingleSelectionModel<T>) selectionModel).setSelected(selectedObject, false);
}
}
}
/**
* if {@link #snapshot()} is set, a new backup if the data provider list will be made. <br/>
* you need to do it when the data provider gets new records.
*
* @param snapshot create a snapshot
*/
public void reset(boolean snapshot) {
if(snapshot)
snapshot();
// flush
clearFilter();
// clear input
filter.setText("");
}
/**
* creates a backup of the orig data provider values
* that a re used to reset the provider when the filter is cleared.
*/
public void snapshot() {
// backup original
this.origValues.clear();
this.origValues.addAll(delegate.getList());
}
public Widget asWidget() {
filter.setMaxLength(30);
filter.setVisibleLength(20);
filter.getElement().setAttribute("style", "width:120px;");
filter.addKeyUpHandler(new KeyUpHandler() {
@Override
public void onKeyUp(KeyUpEvent keyUpEvent) {
Scheduler.get().scheduleDeferred(new Scheduler.ScheduledCommand() {
@Override
public void execute() {
String prefix = filter.getText();
if (prefix != null && !prefix.equals("")) {
// filter by prefix
filterByPrefix(prefix);
} else {
clearFilter();
}
}
});
}
});
HorizontalPanel panel = new HorizontalPanel();
Label label = new Label("Filter: ");
panel.add(label);
panel.add(filter);
label.getElement().setAttribute("style", "padding-top:8px");
return panel;
}
public void filterByPrefix(String prefix) {
clearSelection();
final List<T> next = new ArrayList<T>();
for(T item : origValues)
{
if(predicate.apply(prefix, item))
next.add(item);
}
delegate.getList().clear(); // cannot call setList() as that breaks the sort handler
delegate.getList().addAll(next);
delegate.flush();
}
public void clearFilter() {
delegate.getList().clear(); // cannot call setList() as that breaks the sort handler
delegate.getList().addAll(origValues);
delegate.flush();
}
}