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Make updating a property in one class trigger the setter for a property of that type in another class

I am using MVVM with Galasoft MVVMLight libraries.
I have two models; each has a boolean property and different properties of the same type.
public class Model1 : ObservableObject
{
public EnumPair<YesNoInherit> Model1Property
{
get { return _model1Property; }
set
{
_model1Property = value;
Updated = true
RaisePropertyChanged("Model1Property");
}
}
public bool Updated
{
get { return _updated; }
set
{
_updated = value;
RaisePropertyChanged("Updated");
}
}
}
public class Model2 : ObservableObject
{
public EnumPair<YesNoInherit> Model2Property
{
get { return _model2Property; }
set
{
_model2Property = value;
Updated = true
RaisePropertyChanged("Model2Property");
}
}
public bool Updated
{
get { return _updated; }
set
{
_updated = value;
RaisePropertyChanged("Updated");
}
}
}
The type YesNoInherit is an enum having values No, Yes, and Inherit.
Here is the EnumPair class.
public class EnumPair<T> : ObservableObject where T : struct, IConvertible
{
public T EnumValue
{
get { return _enumValue; }
set
{
if (Type.Equals(value, _enumValue) == false)
{
_enumValue = value;
RaisePropertyChanged();
}
}
}
public string SourceName
{
get { return _sourceName; }
set
{
_sourceName = value;
RaisePropertyChanged();
}
}
}
In my view, I am trying to use a ComboBox to let the user select one of the three enum values, and, in some cases, display custom text. The resource "enumComboBoxTemplate" allows the ComboBox drop-down to show enum descriptions. The converter "inheritanceEnum2Desc" is where the custom text would be applied. "object1" is an instance of "Model1".
<ComboBox ItemTemplate=ItemTemplate="{StaticResource enumComboBoxTemplate}"
EnumSource="enums:YesNoInherit">
<ComboBox.Text>
<MultiBinding Converter="{StaticResource inheritanceEnum2Desc}">
<Binding Path="object1.EnumValue"/>
<Binding Path="object1.SourceName"/>
</MultiBinding>
</ComboBox.Text>
</ComboBox>
"Model2" would be used in future programming employing similar functionality, but with different data.
When I change the selection in the ComboBox, I want to change the value of "Updated" (from false to true) so I can enable a button in the view. This appears to require that the EnumPair class somehow make the program execute the setter for Model1Property. Since the two model classes have properties of type EnumPair, I don't believe I can add any code in EnumPair specific to either model class.
How can I accomplish this? I would greatly appreciate any assistance.

Basically, you have two options: either use some kind of message-bus to update the other model (Prism has EventAggregator, not sure about MVVMLight) or make both model instances forward their properties to a common data source that notifies all of its users when a property changes.

If you want to be able to easily change from one class to another in the future without rewriting all of your code, you need to create an Interface that defines all of the things that the two models have in common, and both model classes need to implement the interface. You could call the interface IModel1
So, instead of having a "Model1" in your viewmodel, you would have an "IModel1" in your viewmodel instead. You could pass in the same object you are passing in now, which is of type Model1, because it implements the IModel1 interface. When you are ready to switch, pass in a Model2 instead, and it will work without having to rewrite anything in your view or viewmodel. Your setters can be completely different - as long as both models have all of the methods and properties that are required by the interface, you will be OK.
Alternately, if Model2 is exactly like Model1 except that it has "extra stuff," you can make Model2 a derived class which derives from Model1.
Google searching either of those terms should point you toward a good tutorial.

Create a custom UserControl using c#

I Created a custom UserControl using Windows Form Control Library.And I want to create a property of UserControlwhich I can add item to it, then I can select item like comboBox.

WinForms allows you to create a rich design-time environment as well as providing for customised editors at runtime for certain properties that you define.
For example, if I plonk a MessageQueue component onto my WinForms form and view the Properties window, I can see a property named Formatter.
Clicking on the Formatter property however displays a drop-down box showing a preset list of values. This is an example of a UI Type Editor.
One way to do this is to define an enum for your supported values (it could be a dynamic list if you wish).
public enum Muppets
{
Kermit,
MissPiggy,
Fozzie
}
...then after defining your own editor derived from UITypeEditor (see MSDN link below)
class MyMuppetEditor : UITypeEditor { ... }
...you attach it to your control's property that you wish to have a drop-down as so:
[Category("Marquee")]
[Browsable(true)]
[EditorAttribute(typeof(MyMuppetEditor),
typeof(System.Drawing.Design.UITypeEditor))]
public Muppets Muppet {get ; set; }
For more detailed information check out the link below.
More
Walkthrough: Implementing a UI Type Editor
Getting the Most Out of the .NET Framework PropertyGrid Control
EDIT: To allow for dynamic list, try making the property a string because that's what the selection will be bound to and during EditValue() when showing your SelectionControl just display a listbox of your dynamic items

You can do this by using the CategoryAttribute class.
Example:
[Description("Description of property here"), Category("Design")]
public bool my_property;
Check out the MSDN page for a more complete reference on how to use it.
EDIT: In the case of wanting to have a bool property, use this example.
private bool my_bool = true; // this is its default value
[PropertyTab("Property Tab Name")]
[Browsable(true)]
[Description("Description of Property"), Category("Data")]
public bool my_property
{
get { return my_bool; }
set { my_bool = value; }
}

I removed my last answer because I misunderstood your point.
An easy solution would require to make a Collection of enum as a property. The Designer property grid will automatically give you the choice among your initialized Collection with a ComboBox. The displayed names will also be the enum's name.
E.g. (something I made for a TextBox that only allows a certain type of value)
The enum :
enum EnumSupportedType
{
Integer = 1,
Double
}
The class where the property is located :
public class NumericTextBox : TextBoxBase, INumericControl
{
private EnumSupportedType _supportedType = EnumSupportedType.Integer;
public EnumSupportedType SupportedType {
get { return _supportedType; }
set { _supportedType = value; }
}
}
Then these items are suggested in a ComboBox (in the Designer property grid) :
Integer
Double
If you can't use enumerations, you can refer to Providing a Custom UI for Your Properties which seems to be a much harder solution to implement but will solve your problem.
I hope it will help you.

Encapsulating ListBox in public property

In a MVP applicaiton if I want to encapsulate a ListBox in a public property so that I could expose the property through an interface to the presenter. I should be able to update the items in the ListBox though this public property. I've tried in several ways to do this
public BindingSource Permission
{
get { return lstGivenPermissions.DataSource; } // Casting error
set { lstGivenPermissions.DataSource = value; }
}
I tried several types for the property like IEnumereble<>, List<> etc. but always either setter or geter shows a casting error.
One option is to have separate properties for get and set.
public ListBox gettingPermission
{
get {return lstGivenPermissions; }
}
public BindingSource Permission
{
set { lstGivenPermissions.DataSource = value; }
}
Is it possible to use a single property in this case or else having two properties is a acceptable solution?
EDIT : I'm using MVP pattern and my requirement is that my presenters are talking to the Views through interfaces. So that if I want one of my presenters to access controllers (like text boxes) in the View, those controllers should be encapsulated in properties. So that I can expose through the interface.

This solved my problem.
public List<string> GivenPermission
{
get { return lstGivenPermissions.Items.Cast<string>().ToList(); }
set { lstGivenPermissions.DataSource = value; }
}

Auto-generate the code-behind name of designer collection items

I have a custom control with a public collection marked as DesignerSerializationVisibility.Content.
When I add items to the collection using the designer, it adds them to the designer file and assigns all desired values but it gives each element of the collection a generic name, such as MyClass1, MyClass2, etc. I want the "Name" property of each item to become the code name of the item so that I can then access the item by its name in code.
This is the functionality of how a ContextMenuStrip and ToolStrip works. In those cases, the Name property shows up as (Name) in the property grid.
Is there an attribute or something I can use to gain this functionality? Or do I have to write a whole custom designer dialog? If so, what's an example of the simplest way I could go about achieving this?

You can try inheriting from Component to get that feature.
In this example, I created a class called PanelItem, which will be the class used in my collection by my own Panel class. I added DesignTimeVisible(false) so that it doesn't populate the component tray in the designer.
Also, I added a Name property that is hidden from the designer but can be used in code. It seemed to work in my tests:
[DesignTimeVisible(false)]
public class PanelItem : Component {
[DefaultValue(typeof(string), "")]
public string PanelText { get; set; }
private string name = string.Empty;
[Browsable(false)]
[DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
public string Name {
get {
if (base.Site != null) {
name = base.Site.Name;
}
return name;
}
set {
name = value;
}
}
}
Then my custom panel control:
public class MyPanel : Panel {
private List<PanelItem> panelItems = new List<PanelItem>();
[DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
public List<PanelItem> PanelItems {
get { return panelItems; }
}
}
Resulted in:

I believe your custom control itself is going to require a DesignerSerializer, and that merely decorating the collection with the the DesignerSerializationVisibility.Content will not be sufficient.
I used ILSpy to check: ToolStrip has its DesignerSerializer set to an internal ToolStripCodeDomSerializer, which I think is responsible for generating all the code properties involved.
I think implementing this will be a bit of specialized work. Here's the MSDN article to get you started: http://msdn.microsoft.com/en-us/library/ms171834.aspx. You're looking for an implementation of the CodeDomSerializer, I believe: http://msdn.microsoft.com/en-us/library/system.componentmodel.design.serialization.codedomserializer.aspx.

How to access properties of a usercontrol in C#

I've made a C# usercontrol with one textbox and one richtextbox.
How can I access the properties of the richtextbox from outside the usercontrol.
For example.. if i put it in a form, how can i use the Text propertie of the richtextbox???
thanks

Cleanest way is to expose the desired properties as properties of your usercontrol, e.g:
class MyUserControl
{
// expose the Text of the richtext control (read-only)
public string TextOfRichTextBox
{
get { return richTextBox.Text; }
}
// expose the Checked Property of a checkbox (read/write)
public bool CheckBoxProperty
{
get { return checkBox.Checked; }
set { checkBox.Checked = value; }
}
//...
}
In this way you can control which properties you want to expose and whether they should be read/write or read-only. (of course you should use better names for the properties, depending on their meaning).
Another advantage of this approach is that it hides the internal implementation of your user control. Should you ever want to exchange your richtext control with a different one, you won't break the callers/users of your control.

Change the access modifier ("Modifiers") of the RichTextBox in the property grid to Public.

Add a property to the usercontrol like this
public string TextBoxText
{
get
{
return textBox1.Text;
}
set
{
textBox1.Text = value;
}
}

I recently had some issues doing this with a custom class:
A user control had a public property which was of a custom class type. The designer by default tries to assign some value to it, so in the designer code, the line userControlThing.CustomClassProperty = null was being automatically added.
The intent was to be able to provide the user control with a custom class at any point while running the program (to change values visible to the user). Because the set {} portion did not check for null values, various errors were cropping up.
The solution was to change the property to a private one, and use two public methods to set and get the value. The designer will try to auto-assign properties, but leaves methods alone.

You need to make a public property for the richtextbox, or expose some other property that does the job of setting the richtextbox text like:
private RichTextBox rtb;
public string RichTextBoxText
{
get
{
return rtb.Text;
}
set
{
rtb.Text = value;
}
}