/*
* Greenshot - a free and open source screenshot tool
* Copyright (C) 2007-2015 Thomas Braun, Jens Klingen, Robin Krom
*
* For more information see: http://getgreenshot.org/
* The Greenshot project is hosted on Sourceforge: http://sourceforge.net/projects/greenshot/
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 1 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see .
*/
using System;
using System.ComponentModel;
using System.Reflection;
namespace Greenshot.Drawing.Fields.Binding
{
///
/// Bidirectional binding of properties of two INotifyPropertyChanged instances.
/// This implementation synchronizes null values, too. If you do not want this
/// behavior (e.g. when binding to a
///
public class BidirectionalBinding
{
private readonly INotifyPropertyChanged _controlObject;
private readonly INotifyPropertyChanged _fieldObject;
private readonly string _controlPropertyName;
private readonly string _fieldPropertyName;
private bool _updatingControl = false;
private bool _updatingField = false;
private IBindingConverter _converter;
private readonly IBindingValidator _validator;
///
/// Whether or not null values are passed on to the other object.
///
protected bool AllowSynchronizeNull = true;
///
/// Bind properties of two objects bidirectionally
///
/// Object containing 1st property to bind
/// Property of 1st object to bind
/// Object containing 2nd property to bind
/// Property of 2nd object to bind
public BidirectionalBinding(INotifyPropertyChanged controlObject, string controlPropertyName, INotifyPropertyChanged fieldObject, string fieldPropertyName)
{
_controlObject = controlObject;
_fieldObject = fieldObject;
_controlPropertyName = controlPropertyName;
_fieldPropertyName = fieldPropertyName;
_controlObject.PropertyChanged += ControlPropertyChanged;
_fieldObject.PropertyChanged += FieldPropertyChanged;
}
///
/// Bind properties of two objects bidirectionally, converting the values using a converter
///
/// Object containing 1st property to bind
/// Property of 1st object to bind
/// Object containing 2nd property to bind
/// Property of 2nd object to bind
/// taking care of converting the synchronized value to the correct target format and back
public BidirectionalBinding(INotifyPropertyChanged controlObject, string controlPropertyName, INotifyPropertyChanged fieldObject, string fieldPropertyName, IBindingConverter converter) : this(controlObject, controlPropertyName, fieldObject, fieldPropertyName)
{
_converter = converter;
}
///
/// Bind properties of two objects bidirectionally, converting the values using a converter.
/// Synchronization can be intercepted by adding a validator.
///
/// Object containing 1st property to bind
/// Property of 1st object to bind
/// Object containing 2nd property to bind
/// Property of 2nd object to bind
/// validator to intercept synchronization if the value does not match certain criteria
public BidirectionalBinding(INotifyPropertyChanged controlObject, string controlPropertyName, INotifyPropertyChanged fieldObject, string fieldPropertyName, IBindingValidator validator) : this(controlObject, controlPropertyName, fieldObject, fieldPropertyName)
{
_validator = validator;
}
///
/// Bind properties of two objects bidirectionally, converting the values using a converter.
/// Synchronization can be intercepted by adding a validator.
///
/// Object containing 1st property to bind
/// Property of 1st object to bind
/// Object containing 2nd property to bind
/// Property of 2nd object to bind
/// taking care of converting the synchronized value to the correct target format and back
/// validator to intercept synchronization if the value does not match certain criteria
public BidirectionalBinding(INotifyPropertyChanged controlObject, string controlPropertyName, INotifyPropertyChanged fieldObject, string fieldPropertyName, IBindingConverter converter, IBindingValidator validator) : this(controlObject, controlPropertyName, fieldObject, fieldPropertyName, converter)
{
_validator = validator;
}
public void ControlPropertyChanged(object sender, PropertyChangedEventArgs e)
{
if (!_updatingControl && e.PropertyName.Equals(_controlPropertyName))
{
_updatingField = true;
Synchronize(_controlObject, _controlPropertyName, _fieldObject, _fieldPropertyName);
_updatingField = false;
}
}
public void FieldPropertyChanged(object sender, PropertyChangedEventArgs e)
{
if (!_updatingField && e.PropertyName.Equals(_fieldPropertyName))
{
_updatingControl = true;
Synchronize(_fieldObject, _fieldPropertyName, _controlObject, _controlPropertyName);
_updatingControl = false;
}
}
private void Synchronize(INotifyPropertyChanged sourceObject, string sourceProperty, INotifyPropertyChanged targetObject, string targetProperty)
{
PropertyInfo targetPropertyInfo = ResolvePropertyInfo(targetObject, targetProperty);
PropertyInfo sourcePropertyInfo = ResolvePropertyInfo(sourceObject, sourceProperty);
if (sourcePropertyInfo != null && targetPropertyInfo != null && targetPropertyInfo.CanWrite)
{
object bValue = sourcePropertyInfo.GetValue(sourceObject, null);
if (_converter != null && bValue != null)
{
bValue = _converter.convert(bValue);
}
try
{
if (_validator == null || _validator.validate(bValue))
{
targetPropertyInfo.SetValue(targetObject, bValue, null);
}
}
catch (Exception e)
{
throw new MemberAccessException("Could not set property '" + targetProperty + "' to '" + bValue + "' [" + (bValue != null ? bValue.GetType().Name : "") + "] on " + targetObject + ". Probably other type than expected, IBindingCoverter to the rescue.", e);
}
}
}
private static PropertyInfo ResolvePropertyInfo(object obj, string property)
{
PropertyInfo ret = null;
string[] properties = property.Split(".".ToCharArray());
for (int i = 0; i < properties.Length; i++)
{
string prop = properties[i];
ret = obj.GetType().GetProperty(prop);
if (ret != null && ret.CanRead && i < prop.Length - 1)
{
obj = ret.GetValue(obj, null);
}
}
return ret;
}
public IBindingConverter Converter
{
get { return _converter; }
set { _converter = value; }
}
}
}