DeleteHandler.java

package at.medevit.elexis.agenda.ui.handler;

import java.util.Optional;

import org.eclipse.core.commands.AbstractHandler;
import org.eclipse.core.commands.ExecutionEvent;
import org.eclipse.core.commands.ExecutionException;
import org.eclipse.core.commands.IHandler;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.StructuredSelection;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.handlers.HandlerUtil;
import org.slf4j.LoggerFactory;

import ch.elexis.agenda.data.Termin;
import ch.elexis.core.data.events.ElexisEventDispatcher;
import ch.elexis.core.model.IPeriod;
import ch.elexis.core.model.IPersistentObject;
import ch.elexis.core.ui.locks.AcquireLockBlockingUi;
import ch.elexis.core.ui.locks.ILockHandler;

public class DeleteHandler extends AbstractHandler implements IHandler {
	
	@Override
	public Object execute(ExecutionEvent event) throws ExecutionException{
		Optional<IPeriod> period = getSelectedPeriod();
		
		period.ifPresent(p -> {
			if (MessageDialog.openConfirm(HandlerUtil.getActiveShell(event), "Löschen",
				"Wollen Sie " + ((IPersistentObject) period.get()).getLabel()
					+ " wirklich löschen?")) {
				AcquireLockBlockingUi.aquireAndRun((IPersistentObject) p, new ILockHandler() {
					@Override
					public void lockFailed(){
						// do nothing
					}
					
					@Override
					public void lockAcquired(){
						((Termin) p).delete();
						ElexisEventDispatcher.reload(Termin.class);
					}
				});
			}
		});
		return null;
	}
	
	private Optional<IPeriod> getSelectedPeriod(){
		try {
			ISelection activeSelection =
				PlatformUI.getWorkbench().getActiveWorkbenchWindow().getActivePage().getSelection();
			if (activeSelection instanceof StructuredSelection
				&& !((StructuredSelection) activeSelection).isEmpty()) {
				Object element = ((StructuredSelection) activeSelection).getFirstElement();
				if (element instanceof IPeriod) {
					return Optional.of((IPeriod) element);
				}
			}
		} catch (Exception e) {
			LoggerFactory.getLogger(getClass()).error("Error setting status", e);
		}
		return Optional.empty();
	}
}