/// <summary>For each element in selection either adds or removes given class.</summary>
/// <param name="ussClass">The class that should be changed</param>
/// <param name="hasClass">Whether the class should be added or removed.</param>
/// <param name="onChange">Function called when the value is different from the new value. Return value can be used to delay the actual change.</param>
public Selection <TElementType, TDataType, TParentDataType> Classed(string ussClass, bool hasClass, OnChangeCall <bool> onChange)
{
ChangeValue(new ClassAccessor(ussClass), hasClass, onChange);
return(this);
}
/// <summary>
///
/// </summary>
/// <typeparam name="TValueType"></typeparam>
/// <param name="acc"></param>
/// <param name="newValue"></param>
/// <param name="onChange">Function (oldValue,newValue) => DDC</param>
internal void ChangeValue <TValueType>(Accessor <TValueType> acc, TValueType newValue, OnChangeCall <TValueType> onChange)
{
//current value is equal to new value -> ignore
TValueType finalExpectedValue = acc.GetValue(Element);
//Change to this value is scheduled ?
var lastRelevantDelayedDataChange = _delayedChanges.LastOrDefault(delayedChange => delayedChange.GetAccessor().Equals(acc));
if (lastRelevantDelayedDataChange != null)
{
finalExpectedValue = ((DelayedDataChange <TValueType>)lastRelevantDelayedDataChange).NewValue;
}
if (EqualityComparer <TValueType> .Default.Equals(finalExpectedValue, newValue))
{
return;
}
var delayed = onChange?.Invoke(finalExpectedValue, newValue);
if (delayed != null)
{
delayed.Initialize(acc, Element, finalExpectedValue, newValue);
_delayedChanges.Add(delayed);
if (lastRelevantDelayedDataChange == null)
{
delayed.Start();
}
}
else
{
acc.SetValue(Element, newValue);
}
}
/// <summary>
/// Generic method for changing a value of all elements of this selection to a single value.
/// </summary>
/// <typeparam name="T">Type of the value that is about to be changed.</typeparam>
/// <param name="accessor">An <see cref="Accessor{T}"/>, which changes the required value</param>
/// <param name="value">A value that is set for each element.</param>
/// <param name="onChangeFunc">Function that is called whenever the new value is different from current value of an element. It can return a <see cref="DelayedDataChange{T}"/>, which is used to delay the actual change.</param>
/// <returns></returns>
public Selection <TElementType, TDataType, TParentDataType> ChangeValue <T>(Accessor <T> accessor, T value, OnChangeCall <T> onChangeFunc = null)
{
Groups.ForEach(group =>
{
TParentDataType parentData = (TParentDataType)group.GroupParent.GetBoundData();
@group.Elements.ForEach(element =>
{
TDataType data = (TDataType)element.GetBoundData();
element.GetOrCreateDataBinding().ChangeValue(accessor, value, (oldValue, newValue) => onChangeFunc?.Invoke(element, data, parentData, oldValue, newValue));
});
});
return(this);
}
