If my array property has null items, then I can't open CollectionEditor from PropertyGrid. I get error with text 'component'. How can I fix it?
public partial class Form1 : Form
{
public Test[] test { get; set; }
public Form1()
{
InitializeComponent();
test = new Test[5];
test[2] = new Test() { Name = "2" };
propertyGrid1.SelectedObject = this;
}
}
[TypeConverter(typeof(ExpandableObjectConverter))]
public class Test
{
public string Name { get; set; }
}
Maybe I should override some methods in my custom CollectionEditor, but i don't know which
It depends exactly how you want to work around this, but if you just need to exclude the null values, then you can override the default ArrayEditor class, something like this;
// define the editor on the property
[Editor(typeof(MyArrayEditor), typeof(UITypeEditor))]
public Test[] test { get; set; }
...
public class MyArrayEditor : ArrayEditor
{
public MyArrayEditor(Type type) : base(type)
{
}
protected override object[] GetItems(object editValue)
{
// filter on the objects you want the array editor to use
return base.GetItems(editValue).Where(i => i != null).ToArray();
}
}
Related
I want to validate elementes within my object Form.
Form form = new Form();
form.Elements.Add(new FormNumberElement());
form.Elements.Add(new FormDateElement());
The form contains a List<FormElement> which holds each element. Here is their definition.
public class Form
{
public List<FormElement> Elements { get; set; } = new();
}
public abstract class FormElement
{
public string Name { get; set; } = string.Empty;
public abstract string GetDefaultName();
}
public class FormNumberElement : FormElement
{
public int MinValue { get; set; }
public override string GetDefaultName() => "Number";
}
public class FormDateElement : FormElement
{
public DateTime MinDate { get; set; }
public override string GetDefaultName() => "Date";
}
Since I'll want every elemnt to have a valid name, I've created this abstract validator.
public abstract class FormElementValidator<T> : AbstractValidator<T> where T : FormElement
{
public FormElementValidator()
{
RuleFor(x => x.Name)
.Must(ValidateName)
.WithMessage("Please enter a name for the element");
}
private bool ValidateName(FormElement element, string name)
{
if (name == element.GetDefaultName())
{
return false;
}
return true;
}
}
I also have two other validators for both the number and the date element.
public class FormNumberElementValidator : FormElementValidator<FormNumberElement>
{
public FormNumberElementValidator() : base()
{
RuleFor(x => x.MinValue)
.GreaterThan(10);
}
}
public class FormDateElementValidator : FormElementValidator<FormDateElement>
{
public FormDateElementValidator() : base()
{
RuleFor(x => x.MinDate)
.GreaterThan(DateTime.Now);
}
}
Now I want to validate each element within my List<FormElement> from my Form object.
My propblem now is that I don't know how I can get the right validator for each indiviual Element.
I've tried to add a method to my base class FormElement
public IValidator<FormElement> GetValidator();
Which I've implemented into every class. For example:
public override IValidator<FormElement> GetValidator() => (IValidator<FormElement>)new FormNumberElementValidator();
But this apporach does not work because the converting to IValidator<FormElement> fails.
How can I get the right validator for each list of my object?
I am trying to create a list of menus which the user can select from a TreeView. Upon selecting a menu from the tree, I want to show the items within that menu in a separate portion of the window. My first thought on a way to do this is to create a class like below:
public class SettingsMenu
{
public string Name { set; get; }
public ObservableCollection<object> Items { set; get; }
public SettingsMenu()
{
Name = "";
Items = new ObservableCollection<object>();
}
public SettingsMenu(string _name, ObservableCollection<object> _items)
{
Name = _name;
Items = _items;
}
public void AddItem(object _item)
{
Items.Add(_item);
}
}
Where "Items" is the items in the menu. I would then create a new instance of this class for each menu in my system, and initialize it with a name and an ObservableCollection of items.
However, the items can be of several custom types. For a basic demonstration of my issue, it would be the equivalent of:
MenuInts = new SettingsMenu("Menu1", new ObservableCollection<int>());
MenuStrings = new SettingsMenu("Menu2", new ObservableCollection<string>());
MenuBools = new SettingsMenu("Menu3", new ObservableCollection<bool>());
But I get a compiler error:
Cannot convert from
'System.Collections.ObjectModel.ObservableCollection<type>' to
'System.Collections.ObjectModel.ObservableCollection<object>'
I would like to use one "Menu" class so that I can use it in a consistent way for display and interaction in the UI. Is there a way to have one master class that can contain an ObservableCollection of any type?
As noted already in Ed Plunkett's comment, you can abstract the functionality you need to a common interface or base class :
public interface ISettingsMenu
{
string Name { set; get; }
IEnumerable<object> Items { get; }
void AddItem(object item);
}
public class SettingsMenu<T> : ISettingsMenu
{
public string Name { set; get; }
public ObservableCollection<T> Items { set; get; }
IEnumerable<object> ISettingsMenu.Items
{
get { return Items.Cast<object>(); }
}
public void AddItem(object item)
{
throw new System.NotImplementedException();
}
public SettingsMenu()
{
Name = "";
Items = new ObservableCollection<T>();
}
public SettingsMenu(string _name, ObservableCollection<T> _items)
{
Name = _name;
Items = _items;
}
public void AddItem(T _item)
{
Items.Add(_item);
}
}
In this example Items is exposed as an IEnumerable - If you need to access the ObservableCollection<T> to bind to its events, you might need to an init method to the interface that accepts the control to bind as a parameter.
I could no longer find an exact solution to my problem in the internet so I'm asking this question. Hope you may be able to help me.
I have the following classes:
public Item
{
public FieldType MyField { get; set; }
public string Description { get; set; }
public int Capacity { get; set; }
}
public FieldType
{
public string Value { get; set; }
public string FieldCode { get; set; }
public string TableCode { get; set; }
}
In my form, I created an instance of Item class. Which contains the following members:
MyField (type of FieldType)
Description (type of string)
Capacity (an int)
Is it possible to only show the Value member of MyField property in the PropertyGrid?
Below is how I assign the selected object property of the PropertyGrid.
void Form1(object sender, EventArgs e)
{
propertyGrid1.SelectedObject = new Item();
}
Yes, easy:
add a computed read only property to Item
public Item
{
public FieldType MyField { get; set; }
public string MyFieldValue => MyField.Value;
public string Description { get; set; }
public int Capacity { get; set; }
}
Im not really sure of what you are looking for but here are 2 answers
1.(as I understood it)
if you want it to show only Value when you try and view the properties of a MyField Instance then all you need to do is add a constructor to the MyField so you can assign the other two values and change the public property to private like so
public FieldType
{
public string Value { get; set; }
private string FieldCode { get; set; }
private string TableCode { get; set; }
}
2.(this will hide the MyField from your propertyGrid)
Override the ToString() method of FielType
like so
public override string ToString()
{
return Value;
}
then set your MyField to private and encapsulate it. returning the instance as a string. which would use the overridden value.
like so
private FieldType MyField;
public string value{ get{return MyField.ToString();}set;}
your MyField will return the overridden ToString value which returns Value.
Solution 1 - Add a property
You can add a property to Item class to get and set MyField.Value:
public string Value
{
get
{
if (MyField != null)
return MyField.Value;
return null;
}
set
{
if (MyField != null)
MyField.Value = value;
}
}
• Preferably define that property in a partial class.
• Use this option when you have access to codes of the classes. If those classes are not yours, use 3rd solution.
Solution 2 - Use ExpandableObjectConverter
You can decorate the MyField property of Item class with ExpandableObjectConverter. Also decorate FieldType with [Browsable(false)] of FieldType class to hide it in property grid if you want:
[TypeConverter(typeof(ExpandableObjectConverter))]
public FieldType MyField { get; set; }
• To customize the text which is shown in front of MyField, you can override ToString method of FieldType and return Value. Also you can do it using a custom TypeConverter and overriding its ConvertTo method.
Solution 3 - Use a custom TypeDescriptor
It's not as easy as the first solution, but the output is completely like what you get using the first solution. It's suitable for cases that you can not manipulate those classes.
You can use it this way:
var item = new Item() { MyField = new FieldType() { Value = "Some Value" } };
TypeDescriptor.AddProvider(new MyTypeDescriptionProvider(), item);
this.propertyGrid1.SelectedObject = item;
Or by decorating Item class with:
[TypeDescriptionProvider(typeof(MyTypeDescriptionProvider))]
public class Item
Custom Property Descriptor
public class MyPropertyDescriptor : PropertyDescriptor
{
private PropertyDescriptor subProperty;
private PropertyDescriptor parentProperty;
public MyPropertyDescriptor(PropertyDescriptor parent, PropertyDescriptor sub)
: base(sub, null)
{
subProperty = sub;
parentProperty = parent;
}
public override bool IsReadOnly { get { return subProperty.IsReadOnly; } }
public override void ResetValue(object component)
{
subProperty.ResetValue(parentProperty.GetValue(component));
}
public override bool CanResetValue(object component)
{
return subProperty.CanResetValue(parentProperty.GetValue(component));
}
public override bool ShouldSerializeValue(object component)
{
return subProperty.ShouldSerializeValue(parentProperty.GetValue(component));
}
public override Type ComponentType { get { return parentProperty.ComponentType; } }
public override Type PropertyType { get { return subProperty.PropertyType; } }
public override object GetValue(object component)
{
return subProperty.GetValue(parentProperty.GetValue(component));
}
public override void SetValue(object component, object value)
{
subProperty.SetValue(parentProperty.GetValue(component), value);
OnValueChanged(component, EventArgs.Empty);
}
}
Custom type Descriptor
public class MyTypeDescriptor : CustomTypeDescriptor
{
ICustomTypeDescriptor original;
public MyTypeDescriptor(ICustomTypeDescriptor originalDescriptor)
: base(originalDescriptor)
{
original = originalDescriptor;
}
public override PropertyDescriptorCollection GetProperties()
{
return this.GetProperties(new Attribute[] { });
}
public override PropertyDescriptorCollection GetProperties(Attribute[] attributes)
{
var properties = original.GetProperties().Cast<PropertyDescriptor>().ToList();
var parent = properties.Where(x => x.Name == "MyField").First();
var sub = TypeDescriptor.GetProperties(typeof(FieldType))["Value"];
properties.Remove(parent);
properties.Add(new MyPropertyDescriptor(parent, sub));
return new PropertyDescriptorCollection(properties.ToArray());
}
}
Custom TypeDescriptorProvider
public class MyTypeDescriptionProvider : TypeDescriptionProvider
{
public MyTypeDescriptionProvider()
: base(TypeDescriptor.GetProvider(typeof(object))) { }
public override ICustomTypeDescriptor GetTypeDescriptor(Type objectType,
object instance)
{
ICustomTypeDescriptor baseDes = base.GetTypeDescriptor(objectType, instance);
return new MyTypeDescriptor(baseDes);
}
}
• Use this option if Item and FieldType are not yours. If those classes are yours and you can change their code, use first solution.
I am inheriting some System.Windows.Forms-Control (about 10 pieces).
Each of them gets some custom extensions, but most of the extension will be the same for each control.
Actually I have to code the same functionality separate for each of them.
This is a lot of copy+paste and difficult to maintain.
class MyButton : Button
{
//this is only in MyButton
public int ButtonProperty { get; set; }
public object Property1 { get; set; }
public object Property2 { get; set; }
public void MakeInvisible()
{
this.Visible = false;
}
}
class MyLabel : Label
{
//this is only in MyLabel
public bool LabelProperty { get; set; }
//same propertys and methods as in MyButton
public object Property1 { get; set; }//copy+paste
public object Property2 { get; set; }//copy+paste
public void MakeInvisible()//copy+paste
{
this.Visible = false;
}
}
What I am searching for is a way to extend all of the derived classes like you can do with an interface or extension method. But I also want to have properties and access the base class (Control)
This is what I am dreaming about:
class MyButton : Button, MyExtension
{
//this is only in MyButton
public int ButtonProperty { get; set; }
}
class MyLabel : Label, MyExtension
{
//this is only in MyLabel
public bool LabelProperty { get; set; }
}
//Extension for all classes inherited from Control
class MyExtension : Control
{
public object Property1 { get; set; }
public object Property2 { get; set; }
public void MakeInvisible()
{
this.Visible = false;
}
}
idea:
create a new type for common properties
give each control a property of that type
implementation:
// TypeConverter required for PropertyGrid in design mode
// found here: http://stackoverflow.com/a/6107953/1506454
[TypeConverter(typeof(ExpandableObjectConverter))]
public class MyExtension
{
// need reference to control to work with in methods
private Control _c;
public MyExtension(Control c)
{
_c = c;
}
// can be inhereted for different controls, if necessary
public string Property1 { get; set; }
public string Property2 { get; set; }
public void MakeInvisible()
{
_c.Visible = false;
}
}
// common interface of extended controls
public interface IExtended
{
MyExtension Extra { get; }
}
// MyButton implements extended interface
public class MyButton : Button, IExtended
{
public MyButton()
{
// create extended properties for button
Extra = new MyExtension(this);
}
// for designer serialization support
[DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
public MyExtension Extra { get; private set; }
//this is only in MyButton
public int ButtonProperty { get; set; }
}
// common extension methods
public static class MyControlHelper
{
public static void MakeInvisible<TControl>(this TControl control) where TControl : Control, IExtended
{
control.Extra.MakeInvisible();
}
public static void Rename<TControl>(this TControl control) where TControl : Control, IExtended
{
control.Text = control.Extra.Property1;
}
}
C# doesn't support multi inheritance. You should try something like this - MyButton : MyExtension; and MyExtension : Button. In this case you will extend MyButton class with MyExtension and Button classes.
You can use extension methods for this purpose
public static class ControlHelper
{
public static void MakeInvisible(this Control c)
{
c.Visible = false;
}
}
and use it like this
var mb = new MyButton();
mb.MakeInvisible();
var ml = new MyLabel();
ml.MakeInvisible();
By using this approach you can generate extension methods for base classes and use it in derived classes.
Instead of inheriting from the Button and Label you could use composition.
class MyExtension
{
protected Control control;
public MyExtension(Control control)
{
this.control = control;
}
public object Property1 { get; set; }
public object Property2 { get; set; }
public void MakeInvisible()
{
this.control.Visible = false;
}
}
class MyButton : MyExtension
{
public MyButton(Button button):base(button){}
public int ButtonProperty { get; set; }
}
class MyLabel : Label
{
public MyButton(Label label):base(label){}
public bool LabelProperty { get; set; }
}
You could even make MyExtension abstract if you don't want any instances of it created. The main difference here is that you'll have to create a Button or Label to pass in and you might want to expose them as properties of your MyButton and MyLabel so you can get at their properties.
If you need to leverage protected methods and properties of the extended controls then you are out of luck, there is no way to acheive what you want without extensive copy and paste.
If you only need access to public methods and properties, then how about something along the following lines:
public interface IControlExtension
{
Foo MyProperty { get; set; }
Blah MyMethod();
}
public abstract class ControlExtension: IControlExtension
{
private Control owner;
private ControlExtension(Control owner)
{
Debug.Assert(owner != null);
this.owner = owner;
}
public static IControlExtension GetControlExtension(Control c)
{
if (c is Button ||
c is Label)
{
return new SimpleControlExtension(c);
}
if (c is Panel || ...
{
return new ContainerControlExtension(c);
}
}
public abstract Foo MyProperty { get; set; }
public abstract Blah MyMethod();
private class SimpleControlExtension: ControlExtension
{
public override Foo MyProperty { .... }
public override Blah MyMethod { ....
}
private class ContainerControlExtension: ControlExtension
{
public override Foo MyProperty { .... }
public override Blah MyMethod { .... }
}
}
Now, in all your extended controls, the copy and paste code is minimum:
public class MyButton : Button
{
public MyButton()
{
....
var controlExtension = ControlExtension.GetControlExtension(this);
}
public IControlExtension { get { return controlExtension; } }
}
I need to enable editing properties of arbitrary objects (the type of object is only known at run-time). I created the following class:
public class Camera
{
[TypeConverter(typeof(ExpandableObjectConverter))]
public object Configuration
{
get
{
return configuration;
}
set
{
configuration = value;
}
}
public Class1 a;
[TypeConverter(typeof(ExpandableObjectConverter))]
public Class1 A
{
get
{
return a;
}
set
{
a = value;
}
}
}
After selecting object "Camera", I can see the property of Class1 on PropertyGrid, but I can't see the property of object "Configuration". How can I fix this problem?
My assumption was that your form becomes visible before the Configuration property was assigned. You didn't supply enough code to see if that was the case. In order to test out my concern, I created two configuration objects:
public class Configuration1
{
public string Test { get; set; }
public byte Test1 { get; set; }
public int Test2 { get; set; }
}
and
public class Configuration2
{
public char Test3 { get; set; }
public List<string> Test4 { get; set; }
}
I modified your camera class to look like this:
public class Camera
{
public Camera()
{
Configuration1 = new Configuration1();
Configuration2 = new Configuration2();
}
private object configuration;
[TypeConverter(typeof(ExpandableObjectConverter))]
public object Configuration { get; set; }
[TypeConverter(typeof(ExpandableObjectConverter))]
public Configuration1 Configuration1 { get; set; }
[TypeConverter(typeof(ExpandableObjectConverter))]
public Configuration2 Configuration2 { get; set; }
}
I then created a form with a PropertyGrid and two Button instances. I configured the form interactions like this:
public partial class Form1 : Form
{
private readonly Camera camera = new Camera();
public Form1()
{
InitializeComponent();
propertyGrid1.SelectedObject = camera;
}
private void Button1Click(object sender, System.EventArgs e)
{
camera.Configuration = new Configuration2();
UpdatePropertyGrid();
}
private void Button2Click(object sender, System.EventArgs e)
{
camera.Configuration = new Configuration1();
UpdatePropertyGrid();
}
private void UpdatePropertyGrid()
{
propertyGrid1.Refresh();
propertyGrid1.ExpandAllGridItems();
}
}
The startup view looks like this:
After clicking the first button:
After clicking the second button:
If you remove the refresh, the property grid does not work correctly. The alternative is to supply an interface with INotifyPropertyChanged on your classes and properties.