gwtquery.plugins.droppable.client.permissionmanagersample2.MemberTreeViewModel.java Source code

Introduction

Here is the source code for gwtquery.plugins.droppable.client.permissionmanagersample2.MemberTreeViewModel.java

Source

/*
 * Copyright 2010 Google 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 gwtquery.plugins.droppable.client.permissionmanagersample2;

import com.google.gwt.cell.client.AbstractCell;
import com.google.gwt.safehtml.shared.SafeHtmlBuilder;
import com.google.gwt.view.client.ListDataProvider;
import com.google.gwt.view.client.SingleSelectionModel;
import com.google.gwt.view.client.TreeViewModel;
import gwtquery.plugins.droppable.client.DroppableOptions;
import gwtquery.plugins.droppable.client.DroppableOptions.DroppableTolerance;
import gwtquery.plugins.droppable.client.gwt.DragAndDropNodeInfo;
import gwtquery.plugins.droppable.client.permissionmanagersample2.MemberDatabase.MemberInfo;
import gwtquery.plugins.droppable.client.permissionmanagersample2.MemberDatabase.Permission;

import java.util.List;

/**
 * The {@link com.google.gwt.view.client.TreeViewModel} used to organize members into a permission
 * hierarchy.
 */
public class MemberTreeViewModel implements TreeViewModel {

    /**
     * A Cell used to render the member inside the tree.
     */
    private static class MemberCell extends AbstractCell<MemberInfo> {

        @Override
        public void render(Context ctx, MemberInfo value, SafeHtmlBuilder sb) {
            if (value != null) {
                sb.appendEscaped(value.getFullName());
            }
        }
    }

    /**
     * The cell used to render permission.
     */
    private static class PermissionCell extends AbstractCell<Permission> {

        public PermissionCell() {
        }

        @Override
        public void render(Context ctx, Permission value, SafeHtmlBuilder sb) {
            if (value != null) {
                sb.appendHtmlConstant("<div style='padding:15px 3px 3px 3px;' >");
                sb.appendEscaped(value.getDisplayName());
                sb.appendHtmlConstant("</div>");
            }
        }
    }

    private MemberCell memberCell;
    private PermissionCell permissionCell;
    private final ListDataProvider<Permission> permissionDataProvider;

    public MemberTreeViewModel() {

        permissionDataProvider = new ListDataProvider<Permission>();
        List<Permission> permissionList = permissionDataProvider.getList();

        for (Permission permission : MemberDatabase.get().queryPermissions()) {
            if (permission != Permission.NON_MEMBER) {
                permissionList.add(permission);
            }
        }

        permissionCell = new PermissionCell();
        memberCell = new MemberCell();

    }

    public <T> NodeInfo<?> getNodeInfo(T value) {

        if (value == null) {
            // permission tree node
            DragAndDropNodeInfo<Permission> permissionNodeInfo = new DragAndDropNodeInfo<Permission>(
                    permissionDataProvider, permissionCell);

            // setup drop operation
            DroppableOptions options = permissionNodeInfo.getDroppableOptions();
            options.setDroppableHoverClass(Resource.INSTANCE.css().droppableHover());

            // permission cell are not draggable
            permissionNodeInfo.setCellDroppableOnly();
            return permissionNodeInfo;

        } else if (value instanceof Permission) {
            // member tree node
            Permission p = (Permission) value;

            ListDataProvider<MemberInfo> dataProvider = MemberDatabase.get().getDataProvider(p);

            return createNodeInfoForMembers(dataProvider);

        } else if (value instanceof MemberInfo) {
            MemberInfo memberInfo = (MemberInfo) value;

            ListDataProvider<MemberInfo> dataProvider = MemberDatabase.get().getDataProvider(value);

            return createNodeInfoForMembers(dataProvider);
        }

        String type = value.getClass().getName();
        throw new IllegalArgumentException("Unsupported object type: " + type);
    }

    public boolean isLeaf(Object value) {
        return false;
    }

    private DragAndDropNodeInfo<MemberInfo> createNodeInfoForMembers(
            ListDataProvider<MemberInfo> listDataProvider) {
        DragAndDropNodeInfo<MemberInfo> memberNodeInfo = new DragAndDropNodeInfo<MemberInfo>(listDataProvider,
                memberCell, new SingleSelectionModel<MemberInfo>(), null);

        // setup the drag operation
        PermissionManagerSample2.configureDragOperation(memberNodeInfo.getDraggableOptions());

        memberNodeInfo.getDroppableOptions().setTolerance(DroppableTolerance.INTERSECT);

        return memberNodeInfo;
    }

}