/// <summary>
/// Returns the default property for this instance of a component.
/// </summary>
/// <returns>
/// A <see cref="T:System.ComponentModel.PropertyDescriptor"/> that represents the default property for this object, or null if this object does not have properties.
/// </returns>
PropertyDescriptor ICustomTypeDescriptor.GetDefaultProperty()
{
PropertySpecification propertySpec = this.PropertySpecifications.FirstOrDefault(p => p.Name == this.DefaultProperty);
return(propertySpec == null ? null : new PropertySpecificationDescriptor(propertySpec, this,
new Attribute[] { new MergablePropertyAttribute(true) }));
}
/// <summary>
/// Returns a collection of standard values for the data type this type converter is designed for when provided with a format context.
/// </summary>
/// <param name="context">An <see cref="T:System.ComponentModel.ITypeDescriptorContext"/> that provides a format context that can be used to extract additional information about the environment from which this converter is invoked. This parameter or properties of this parameter can be null.</param>
/// <returns>
/// A <see cref="T:System.ComponentModel.TypeConverter.StandardValuesCollection"/> that holds a standard set of valid values, or null if the data type does not support a standard set of values.
/// </returns>
public override StandardValuesCollection GetStandardValues(ITypeDescriptorContext context)
{
if ((context == null) || (context.PropertyDescriptor == null) || (context.PropertyDescriptor.ComponentType == null) ||
(context.PropertyDescriptor.ComponentType != typeof(PropertySpecification)))
{
return(base.GetStandardValues(context));
}
PropertySpecificationDescriptor specificationDescriptor = context.PropertyDescriptor as PropertySpecificationDescriptor;
if (specificationDescriptor == null)
{
// check if the property descriptor is a multi-property descriptor, which is created by various property grids when multiple objects are
// merged and displayed simultaneously.
var itemProperty = context.PropertyDescriptor.GetType().GetProperty("Item");
if (itemProperty == null)
{
return(base.GetStandardValues(context));
}
try
{
specificationDescriptor = itemProperty.GetValue(context.PropertyDescriptor, new object[] { 0 }) as PropertySpecificationDescriptor;
if (specificationDescriptor == null)
{
// give up
return(base.GetStandardValues(context));
}
}
catch
{
// no descriptor at index 0
return(base.GetStandardValues(context));
}
}
PropertySpecification specification = specificationDescriptor.Specification;
if ((specification == null) || (specification.ValueList == null) || (specification.ValueList.Count <= 0))
{
return(base.GetStandardValues(context));
}
return(new StandardValuesCollection(specification.ValueList));
}
public void AdvancedPropertyDescriptorConstructionTestWithEvents()
{
PropertyBag bag = new PropertyBag();
// add some property specifications.
var property1 = new PropertySpecification("Property 1", typeof(string), "Cat1", "Prop1 desc", "Foo");
// make readonly
property1.Attributes.Add(ReadOnlyAttribute.Yes);
bag.PropertySpecifications.Add(property1);
// add expanding property
var property2 = new PropertySpecification("Picture", typeof(Image), "Some Category", "This is a sample description.");
property2.Attributes.Add(new TypeConverterAttribute(typeof(ExpandableObjectConverter)));
bag.PropertySpecifications.Add(property2);
// custom editor
var property3 = new PropertySpecification("Source folder", typeof(string), "OutputFolders", "The output folder for the sourcecode", "c:\\temp");
property3.Attributes.Add(new EditorAttribute(typeof(System.Windows.Forms.Design.FolderNameEditor), typeof(System.Drawing.Design.UITypeEditor)));
bag.PropertySpecifications.Add(property3);
// use value list
var property4 = new PropertySpecification("PickAValue", typeof(string), "Cat1", "A property which value has to be picked from a list");
property4.TypeConverterType = typeof(PropertySpecificationValuesListTypeConverter);
property4.ValueList.AddRange(new[] { "One", "Two", "Three", "Many" });
bag.PropertySpecifications.Add(property4);
// value list to store values in
Dictionary<string, object> values = new Dictionary<string, object>();
// event handler binding so values get store inside the dictionary and also retrieved from it.
bag.GetValue += (sender, e) => { e.Value = values.GetValue(e.Property.Name); };
bag.SetValue += (sender, e) => { values[e.Property.Name] = e.Value; };
// open a testform which binds the bag to the propertygrid. Editing values will store the values in the dictionary, default values are
// not in the dictionary.
using(TestForm f = new TestForm(bag))
{
f.ShowDialog();
}
}
/// <summary>
/// Initializes a new instance of the <see cref="PropertySpecificationDescriptor"/> class.
/// </summary>
/// <param name="specification">The specification.</param>
/// <param name="containingBag">The containing bag.</param>
/// <param name="propertyAttributes">The property attributes.</param>
public PropertySpecificationDescriptor(PropertySpecification specification, PropertyBag containingBag, Attribute[] propertyAttributes)
: base(specification.Name, propertyAttributes)
{
_containingBag = containingBag;
_specification = specification;
}
/// <summary>
/// Initializes a new instance of the PropertySpecEventArgs class.
/// </summary>
/// <param name="property">The PropertySpec that represents the property whose value is being requested or set.</param>
/// <param name="val">The current value of the property.</param>
public PropertySpecificationEventArgs(PropertySpecification property, object val)
{
ArgumentVerifier.CantBeNull(property, "property");
this.Property = property;
this.Value = val;
}
/// <summary>
/// Initializes a new instance of the PropertySpecEventArgs class.
/// </summary>
/// <param name="property">The PropertySpec that represents the property whose value is being requested or set.</param>
/// <param name="val">The current value of the property.</param>
public PropertySpecificationEventArgs(PropertySpecification property, object val)
{
ArgumentVerifier.CantBeNull(property, "property");
this.Property = property;
this.Value = val;
}
public void AdvancedPropertyDescriptorConstructionTestWithFuncs()
{
PropertyBag bag = new PropertyBag();
// add some property specifications.
var property1 = new PropertySpecification("Property 1", typeof(string), "Cat1", "Prop1 desc", "Foo");
// make readonly
property1.Attributes.Add(ReadOnlyAttribute.Yes);
bag.PropertySpecifications.Add(property1);
// add expanding property
var property2 = new PropertySpecification("Picture", typeof(Image), "Some Category", "This is a sample description.");
property2.Attributes.Add(new TypeConverterAttribute(typeof(ExpandableObjectConverter)));
bag.PropertySpecifications.Add(property2);
// custom editor
var property3 = new PropertySpecification("Source folder", typeof(string), "OutputFolders", "The output folder for the sourcecode", "c:\\temp");
property3.Attributes.Add(new EditorAttribute(typeof(System.Windows.Forms.Design.FolderNameEditor), typeof(System.Drawing.Design.UITypeEditor)));
property3.ConvertEmptyStringToNull = true;
bag.PropertySpecifications.Add(property3);
// use value list
var property4 = new PropertySpecification("PickAValue", typeof(string), "Cat1", "A property which value has to be picked from a list", "One");
property4.TypeConverterType = typeof(PropertySpecificationValuesListTypeConverter);
property4.ValueList.AddRange(new[] { "One", "Two", "Three", "Many" });
bag.PropertySpecifications.Add(property4);
var property5 = new PropertySpecification("EnumValue", typeof(ConsoleColor), "Cat1", "Enum property to see that values are converted back/forth to int");
bag.PropertySpecifications.Add(property5);
// value list to store values in
Dictionary<string, object> values = new Dictionary<string, object>();
// func setting so values get store inside the dictionary and also retrieved from it. Console write added to see what happens when you bind
// a windows forms propertygrid to a bag: many many redundant calls to the getters/setters occur.
bag.ValueGetterFunc = (s) =>
{
var v = values.GetValue(s);
Console.WriteLine("Get: {0} : {1}", s, v ?? "<null>");
return v;
};
bag.ValueSetterFunc = (s, v) =>
{
values[s] = v;
Console.WriteLine("Set: {0} : {1}", s, v ?? "<null>");
};
// open a testform which binds the bag to the propertygrid. Editing values will store the values in the dictionary, default values are
// not in the dictionary.
using(TestForm f = new TestForm(bag))
{
f.ShowDialog();
}
}
/// <summary>
/// Initializes a new instance of the <see cref="PropertySpecificationDescriptor"/> class.
/// </summary>
/// <param name="specification">The specification.</param>
/// <param name="containingBag">The containing bag.</param>
/// <param name="propertyAttributes">The property attributes.</param>
public PropertySpecificationDescriptor(PropertySpecification specification, PropertyBag containingBag, Attribute[] propertyAttributes) :
base(specification.Name, propertyAttributes)
{
_containingBag = containingBag;
_specification = specification;
}
