public BindingExpression Create(IViewModel viewModel, String elementId, String targetProperty, Binding binding)
{
var type = viewModel.GetType();
// find property dic
IDictionary<string, MemberInfo> propertyDic;
if(!_typeBindingDic.TryGetValue(type, out propertyDic))
{
propertyDic = new Dictionary<string, MemberInfo>();
_typeBindingDic[type] = propertyDic;
}
MemberInfo propertyInfo = null;
if(!propertyDic.TryGetValue(targetProperty, out propertyInfo))
{
// find the member...
propertyInfo = type.GetMember(targetProperty).FirstOrDefault();
if(propertyInfo == null)
{
return null;
}
propertyDic[targetProperty] = propertyInfo;
}
var bindingExpression = new BindingExpression(binding, propertyInfo, viewModel);
return bindingExpression;
}
public static IBindingExpression SetBinding(IBindable target, Binding binding)
{
if (target == null)
throw new ArgumentNullException("target");
if (binding == null)
throw new ArgumentNullException("binding");
var targetProperty = binding.TargetPath;
IBindingExpression bindingExpression = null;
object dataBinding = target.DataBinding;
object nestedTarget = dataBinding;
var element = target as IElement;
MemberInfo memberInfo = null;
FieldInfo bindablePropertyInfo = null;
if (dataBinding != null)
{
var name = string.Concat(targetProperty, "Property");
bindablePropertyInfo = dataBinding.GetType().GetField(name, BindingFlags.Public | BindingFlags.Static | BindingFlags.Instance | BindingFlags.FlattenHierarchy);
name = string.Concat(name, ".ControlValue");
memberInfo = dataBinding.GetType().GetNestedMember(ref nestedTarget, name, false);
if (memberInfo != null)
{
binding.TargetPath = name;
binding.Target = nestedTarget;
}
}
var targetReady = memberInfo != null && nestedTarget != null && binding.Source != null;
if (targetReady)
{
if (_BindingExpressions == null)
_BindingExpressions = new List<IBindingExpression>();
bindingExpression = GetBindingExpression(binding);
if (bindingExpression != null)
{
_BindingExpressions.Remove(bindingExpression);
}
bindingExpression = new BindingExpression(binding, memberInfo, nestedTarget) { Element = element };
_BindingExpressions.Add(bindingExpression);
var vmINPC = bindingExpression.Binding.Source as INotifyPropertyChanged;
if (vmINPC != null)
{
vmINPC.PropertyChanged -= HandleDataContextPropertyChanged;
vmINPC.PropertyChanged += HandleDataContextPropertyChanged;
}
var viewINPC = bindingExpression.Binding.ViewSource as INotifyPropertyChanged;
if (viewINPC != null)
{
viewINPC.PropertyChanged -= HandleDataContextPropertyChanged;
viewINPC.PropertyChanged += HandleDataContextPropertyChanged;
}
var sourceValue = bindingExpression.GetSourceValue();
var sourceCollection = sourceValue as INotifyCollectionChanged;
if (sourceCollection != null)
{
SetNotificationCollectionHandler(bindingExpression, sourceCollection);
}
}
else
{
var binderKey =_Bindings.SingleOrDefault((kvp)=>kvp.Key.Object == target && kvp.Key.Property == targetProperty).Key;
if (binderKey == null)
_Bindings.Add(new PropertyBinder() { Object = target, Property = targetProperty }, binding);
else
_Bindings[binderKey] = binding;
}
if (bindablePropertyInfo != null)
{
var bindableProperty = bindablePropertyInfo.GetValue(dataBinding) as BindableProperty;
if (bindableProperty != null)
bindableProperty.BindingExpression = bindingExpression;
}
return bindingExpression;
}