AbstractListActivity.java

/*
 * Copyright 2014-2016 CyberVision, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.kaaproject.kaa.server.admin.client.mvp.activity;

import com.google.gwt.activity.shared.AbstractActivity;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.event.shared.EventBus;
import com.google.gwt.event.shared.HandlerRegistration;
import com.google.gwt.place.shared.Place;
import com.google.gwt.user.client.rpc.AsyncCallback;
import com.google.gwt.user.client.ui.AcceptsOneWidget;

import org.kaaproject.avro.ui.gwt.client.util.BusyAsyncCallback;
import org.kaaproject.avro.ui.gwt.client.widget.grid.AbstractGrid;
import org.kaaproject.avro.ui.gwt.client.widget.grid.event.RowActionEvent;
import org.kaaproject.avro.ui.gwt.client.widget.grid.event.RowActionEventHandler;
import org.kaaproject.kaa.common.dto.HasId;
import org.kaaproject.kaa.server.admin.client.mvp.ClientFactory;
import org.kaaproject.kaa.server.admin.client.mvp.activity.grid.AbstractDataProvider;
import org.kaaproject.kaa.server.admin.client.mvp.event.data.DataEvent;
import org.kaaproject.kaa.server.admin.client.mvp.event.data.DataEventHandler;
import org.kaaproject.kaa.server.admin.client.mvp.place.TreePlace;
import org.kaaproject.kaa.server.admin.client.mvp.view.BaseListView;
import org.kaaproject.kaa.server.admin.client.util.Utils;

import java.util.ArrayList;
import java.util.List;

public abstract class AbstractListActivity<T extends HasId, P extends TreePlace>
    extends AbstractActivity implements BaseListView.Presenter {

  protected final ClientFactory clientFactory;
  protected final Class<T> dataClass;

  protected AbstractDataProvider<T, String> dataProvider;

  protected List<HandlerRegistration> registrations = new ArrayList<HandlerRegistration>();

  protected BaseListView<T> listView;
  protected P place;

  /**
   * The constructor.
   */
  public AbstractListActivity(P place, Class<T> dataClass, ClientFactory clientFactory) {
    this.place = place;
    this.clientFactory = clientFactory;
    this.dataClass = dataClass;
  }

  @Override
  public void start(AcceptsOneWidget containerWidget, EventBus eventBus) {
    listView = getView();
    this.dataProvider = getDataProvider(listView.getListWidget());
    listView.setPresenter(this);
    bind(eventBus);
    containerWidget.setWidget(listView.asWidget());
  }

  protected abstract BaseListView<T> getView();

  protected abstract AbstractDataProvider<T, String> getDataProvider(
      AbstractGrid<T, String> dataGrid);

  protected abstract Place newEntityPlace();

  protected abstract Place existingEntityPlace(String id);

  protected abstract void deleteEntity(String id, AsyncCallback<Void> callback);

  @Override
  public void onStop() {
    for (HandlerRegistration registration : registrations) {
      registration.removeHandler();
    }
    registrations.clear();
  }

  /**
   * Navigate to a new Place in the browser.
   */
  public void goTo(Place place) {
    clientFactory.getPlaceController().goTo(place);
  }

  /**
   * Bind method.
   *
   * @param eventBus the event bus
   */
  public void bind(final EventBus eventBus) {

    listView.clearError();

    registrations.add(listView.getAddButton().addClickHandler(new ClickHandler() {
      public void onClick(ClickEvent event) {
        goTo(newEntityPlace());
      }
    }));

    registrations.add(listView.getRowActionsSource().addRowActionHandler(
        new RowActionEventHandler<String>() {
          @Override
          public void onRowAction(RowActionEvent<String> event) {
            String id = event.getClickedId();
            if (event.getAction() == RowActionEvent.CLICK) {
              goTo(existingEntityPlace(id));
            } else if (event.getAction() == RowActionEvent.DELETE) {
              deleteEntity(id, new BusyAsyncCallback<Void>() {
                @Override
                public void onFailureImpl(Throwable caught) {
                  Utils.handleException(caught, listView);
                }

                @Override
                public void onSuccessImpl(Void result) {
                }
              });
            }
            onCustomRowAction(event);
          }
        }));

    registrations.add(eventBus.addHandler(DataEvent.getType(), new DataEventHandler() {
      @Override
      public void onDataChanged(DataEvent event) {
        if (event.checkClass(dataClass)) {
          dataProvider.reload();
          onCustomDataChangedEvent(event);
        }
      }
    }));

    final Place previousPlace = place.getPreviousPlace();
    if (previousPlace != null) {
      listView.setBackEnabled(true);
      registrations.add(listView.getBackButton().addClickHandler(new ClickHandler() {
        public void onClick(ClickEvent event) {
          goTo(previousPlace);
        }
      }));
    }
  }

  protected void onCustomRowAction(RowActionEvent<String> event) {
  }

  protected void onCustomDataChangedEvent(DataEvent event) {
  }

}