| // Licensed to the Apache Software Foundation (ASF) under one |
| // or more contributor license agreements. See the NOTICE file |
| // distributed with this work for additional information |
| // regarding copyright ownership. The ASF licenses this file |
| // to you 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. |
| |
| using System.Collections.Generic; |
| using System.ComponentModel.Composition; |
| using System.Linq; |
| using System.Collections.Specialized; |
| |
| namespace Ambari.SCOM.Widgets.Components { |
| [Export, PartCreationPolicy(CreationPolicy.NonShared)] |
| public class CollectionElementAccessor : InitializableComponentBase { |
| private IEnumerable<object> collection; |
| public IEnumerable<object> Collection { |
| get { return collection; } |
| set { |
| if (collection == value) return; |
| |
| if (collection is INotifyCollectionChanged) |
| ((INotifyCollectionChanged)collection).CollectionChanged -= OnInputCollectionChanged; |
| |
| collection = value; |
| |
| if (collection is INotifyCollectionChanged) |
| ((INotifyCollectionChanged)collection).CollectionChanged += OnInputCollectionChanged; |
| |
| NotifyPropertyChanged("Collection"); |
| SelectElement(); |
| } |
| } |
| |
| private int elementIndex; |
| public int ElementIndex { |
| get { return elementIndex; } |
| set { |
| if (elementIndex == value) return; |
| elementIndex = value; |
| NotifyPropertyChanged("ElementIndex"); |
| SelectElement(); |
| } |
| } |
| |
| private object element; |
| public object Element { |
| get { return element; } |
| set { |
| if (element == value) return; |
| element = value; |
| NotifyPropertyChanged("Element"); |
| } |
| } |
| |
| protected override void Initialize() { |
| SelectElement(); |
| } |
| |
| private void SelectElement() { |
| if (!IsInitialized) return; |
| if (elementIndex < 0 || collection == null || |
| elementIndex >= collection.Count()) { |
| Element = null; |
| } else { |
| Element = collection.Skip(elementIndex).First(); |
| } |
| } |
| |
| private void OnInputCollectionChanged(object sender, NotifyCollectionChangedEventArgs e) { |
| SelectElement(); |
| } |
| } |
| } |