Why custom control task pane does not update its properties? - c#

I have designed a custom panel which can expand or collapse form at run time.
When I change its height from custom designed task, it does not update it.
Code of my control class:
using System;
using System.Windows.Forms;
using System.ComponentModel;
using System.ComponentModel.Design;
using System.Windows.Forms.Design;
[Designer(typeof(MyControlDesigner))]
public partial class ExpandCollapsePanel : UserControl
{
private bool flag = false;
private Size size;
public int usrVerticalSize;
public ExpandCollapsePanel()
{
InitializeComponent();
}
[DefaultValueAttribute(true)]
public int SetVerticalSize
{
get
{
return usrVerticalSize;
}
set
{
usrVerticalSize = value;
}
}
Code of taskpanedesign class:
namespace ExpandCollapseFormLibrary
{
class CustomDialogue : ControlDesigner
{
private DesignerActionListCollection actionLists;
public override DesignerActionListCollection ActionLists
{
get
{
if (actionLists == null)
{
actionLists = new DesignerActionListCollection();
actionLists.Add(new MyActionListItem(this));
}
return actionLists;
}
}
}
internal class MyActionListItem : DesignerActionList
{
public MyActionListItem(ControlDesigner owner) : base(owner.Component)
{
}
public override DesignerActionItemCollection GetSortedActionItems()
{
var items = new DesignerActionItemCollection();
//items.Add(new DesignerActionTextItem("Hello world", "Misc"));
items.Add(new DesignerActionPropertyItem("Checked", "Vertical Drop Down Size"));
return items;
}
public int Checked
{
get { return ((ExpandCollapsePanel)base.Component).SetVerticalSize; }
set { ((ExpandCollapsePanel)base.Component).SetVerticalSize = value; }
}
}
}
When I change the value the Form1(where drag and dropped) designed class keep it permanently.

the SetVerticalSize property value of your custom pane's is really changed, but the problem is that the designer host does not know about it at all. To notify the designer host about your custom pane changing you should implement something like this (I suggest you read the IComponentChangeService MSDN article for more details):
int usrVerticalSize;
[DefaultValue(true)]
public int SetVerticalSize {
get { return usrVerticalSize; }
set {
FireChanging(); //changing notification
try {
usrVerticalSize = value;
}
finally { FireChanged(); } //changed notification
}
}
void FireChanging() {
IComponentChangeService service = GetComponentChangeService();
if(service != null)
service.OnComponentChanging(this, null);
}
void FireChanged() {
IComponentChangeService service = GetComponentChangeService();
if(service != null)
service.OnComponentChanged(this, null, null, null);
}
IComponentChangeService GetComponentChangeService() {
return GetService(typeof(IComponentChangeService)) as IComponentChangeService;
}

Related

MAUI CreatePlatformView is never called?

I have been trying out MAUI extensively lately and was trying to Create a Custom Control I guess and I ran into this weird problem, the CreatePlatform method was never getting called, at first I thought this was because I was using a MAUI class library and there was some issue with them, So instead I created another control in the same MAUI project instead of doing it through a CL and to my surprise even then it did not work.
My code is as follows:
Interface:
public interface IExtendedLabel : ILabel
{
bool HasUnderline { get; }
Color UnderlineColor { get; }
}
Label class:
public class ExtendedLabel : Label, IExtendedLabel
{
public readonly BindableProperty HasUnderlineProperty = BindableProperty.Create(
nameof(HasUnderline),
typeof(bool),
typeof(ExtendedLabel),
true);
public bool HasUnderline
{
get => (bool)GetValue(HasUnderlineProperty);
set => SetValue(HasUnderlineProperty, value);
}
public readonly BindableProperty UnderlineColorProperty = BindableProperty.Create(
nameof(UnderlineColor),
typeof(Color),
typeof(ExtendedLabel),
Colors.Black);
public Color UnderlineColor
{
get => (Color)GetValue(HasUnderlineProperty);
set => SetValue(HasUnderlineProperty, value);
}
}
My shared handler:
using System;
using MAUI.FreakyControls;
using Microsoft.Maui.Handlers;
#if ANDROID
using NativeView = AndroidX.AppCompat.Widget.AppCompatTextView;
#endif
#if IOS
using NativeView = UIKit.UILabel;
#endif
namespace Samples
{
public partial class ExtendedLabelHandler : ViewHandler<IExtendedLabel,NativeView>
{
#region ctor
public static CommandMapper<IExtendedLabel, ExtendedLabelHandler> CommandMapper = new(ViewCommandMapper);
public ExtendedLabelHandler() : base(FreakyEditorMapper)
{
}
public ExtendedLabelHandler(IPropertyMapper mapper = null) : base(mapper ?? FreakyEditorMapper)
{
}
#endregion
#region Mappers
public static IPropertyMapper<IExtendedLabel, ExtendedLabelHandler> FreakyEditorMapper = new PropertyMapper<IExtendedLabel, ExtendedLabelHandler>(ViewMapper)
{
[nameof(IExtendedLabel.HasUnderline)] = MapHasUnderlineWithColor,
[nameof(IExtendedLabel.UnderlineColor)] = MapHasUnderlineWithColor
};
public static void MapHasUnderlineWithColor(ExtendedLabelHandler handler, IExtendedLabel entry)
{
}
#endregion
}
}
Handler Android:
public partial class ExtendedLabelHandler
{
protected override AppCompatTextView CreatePlatformView()
{
var nativeView = new AppCompatTextView(this.Context)
{
};
return nativeView;
}
private void HandleNativeHasUnderline(bool hasUnderline, Color underlineColor)
{
if (hasUnderline)
{
var AndroidColor = underlineColor.ToNativeColor();
var colorFilter = BlendModeColorFilterCompat.CreateBlendModeColorFilterCompat(
AndroidColor, BlendModeCompat.SrcIn);
PlatformView.Background?.SetColorFilter(colorFilter);
}
else
{
PlatformView.Background?.ClearColorFilter();
}
}
}
My iOS handler:
public partial class ExtendedLabelHandler
{
CoreAnimation.CALayer bottomLine;
protected override UILabel CreatePlatformView()
{
return new UILabel();
}
private void HandleNativeHasUnderline(bool hasUnderline, Color underlineColor)
{
if (hasUnderline)
{
var uiColor = underlineColor.ToNativeColor();
bottomLine = BottomLineDrawer(uiColor);
bottomLine.Frame = new CGRect(x: 0, y: PlatformView.Frame.Size.Height - 5,
width: PlatformView.Frame.Size.Width, height: 1);
PlatformView.Layer.AddSublayer(bottomLine);
PlatformView.Layer.MasksToBounds = true;
}
else
{
bottomLine?.RemoveFromSuperLayer();
}
}
}
Adding the handler:
handlers.AddHandler(typeof(IExtendedLabel), typeof(ExtendedLabelHandler));
Am I doing something wrong?
You can find the full code on my repo here which has a full working example of the method never getting called for some reason: https://github.com/FreakyAli/MAUI.FreakyControls/tree/r1-gh/feat/freakyeditor
Update
So I am not sure if this is a bug or not but I have raised one in GitHub anyway, which can be tracked here: https://github.com/dotnet/maui/issues/9720
So the issue was my registration, I was registering my interface instead of the class of my custom control:
handlers.AddHandler(typeof(ExtendedLabel), typeof(ExtendedLabelHandler));

How to replicate the behavior on design time of Location and Font property (To give an example)

I want to set a property which contains other properties inside (Like font or Location Properties), I've done the following:
class Example:DataGridView
{
private PlusProperties X;
public Example()
{
X = new PlusProperties();
AdditionalProperties = X;
}
[ComVisibleAttribute(true)]
[System.ComponentModel.Browsable(true), System.ComponentModel.EditorBrowsable(System.ComponentModel.EditorBrowsableState.Always)]
[System.ComponentModel.DesignerSerializationVisibility(System.ComponentModel.DesignerSerializationVisibility.Content)]
public PlusProperties AdditionalProperties
{
get { return X; }
set
{
X = value;
}
}
}
public class PlusProperties
{
private Color Pcolor = Color.DimGray;
private Color Ccolor = Color.DimGray;
public PlusProperties()
{
}
[System.ComponentModel.Browsable(true), System.ComponentModel.EditorBrowsable(System.ComponentModel.EditorBrowsableState.Always)]
public Color ParentColor
{
get { return Pcolor; }
set
{
if (value != Pcolor)
{
Pcolor = value;
}
}
}
[System.ComponentModel.Browsable(true), System.ComponentModel.EditorBrowsable(System.ComponentModel.EditorBrowsableState.Always)]
public Color ChildColor
{
get { return Ccolor; }
set
{
if (value != Ccolor)
{
Ccolor = value;
}
}
}
}
How can achieve the same behavior on design time (I mean show the properties of the class)?
Thanks in advance for your help.
You'll want to create a class that inherits ExpandableObjectConverter and add a TypeConverter attribute to your class that uses it. See the following example here: https://msdn.microsoft.com/en-us/library/system.componentmodel.expandableobjectconverter(v=vs.110).aspx

How to set UserControl's Custom Property, which is a class, from Properties Window

I have created a UserControl which extends PictureBox Control
public partial class AudioMonitor : PictureBox
{
private SelectionSettings _selectionSettings;
[Description("Various settings regarding to the selection visuals"), Category("Custom")]
[Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
public SelectionSettings SelectionSettings
{
get { return this._selectionSettings; }
set { this._selectionSettings = value; }
}
}
SelectionSettings property is a custom class which I have created as follows:
[Serializable]
public class SelectionSettings
{
private SelectionMarker _startMarker;
private SelectionMarker _endMarker;
private SelectionPen _selectionStyle;
public SelectionMarker StartMarker
{
get { return this._startMarker; }
set { this._startMarker = value; }
}
public SelectionMarker EndMarker
{
get { return this._endMarker; }
set { this._endMarker = value; }
}
public SelectionPen SelectionStyle
{
get { return this._selectionStyle; }
set { this._selectionStyle = value; }
}
}
[Serializable]
public class SelectionMarker
{
private Color _color = Color.White;
private DashStyle _style = DashStyle.Solid;
private float _width = 1.0F;
public Color Color
{
get { return this._color; }
set { this._color = value; }
}
public DashStyle Style
{
get { return this._style; }
set { this._style = value; }
}
public float Width
{
get { return this._width; }
set { this._width = value; }
}
public Pen Pen
{
get
{
Pen pen = new Pen(this._color);
pen.DashStyle = this._style;
pen.Width = this._width;
return pen;
}
}
}
[Serializable]
public class SelectionPen
{
private Color _color = Color.White;
private DashStyle _style = DashStyle.Solid;
private float _width = 1.0F;
private float _alpha = 100;
public Color Color
{
get { return this._color; }
set { this._color = value; }
}
public DashStyle Style
{
get { return this._style; }
}
public float Width
{
get { return this._width; }
}
public float Alpha
{
get { return this._alpha; }
}
public int AlphaPercent
{
get { return (int)Math.Round(this._alpha * 100 / 255); }
set
{
if (value > 0 && value <= 100)
this._alpha = (value * 255 / 100);
else
throw new ArgumentException("Alpha percentage should be between (0, 100]");
}
}
public Pen Pen
{
get
{
Pen pen = new Pen(Color.FromArgb((byte)this._alpha, this._color.R, this._color.G, this._color.B));
pen.DashStyle = this._style;
pen.Width = this._width;
return pen;
}
}
}
When I place my custom control on a Form and open the Properties Window I can see it as follows :
As you can see I can not set "SelectionSettings" property from the "Properties" window at the design time. What I need is to place the "..." button next to the Property name and open a pop-up to set values.
It should look something like this :
How can I accomplish this task?
What you want to do is add an Editor to AudioMonitor's SelectionSettings property.
To do this, you should create a custom class derived from the UITypeEditor Class.
In order to inherit from UITypeEditor, your project must reference System.Design, which can be done by going to the Project menu, selecting Add Reference to bring up the Reference Manager, navigating to Assemblies->Framework on the left panel and making sure System.Design is checked in the list.
In your custom UITypeEditor derived class, override the method EditValue to bring up a custom dialog that edits a value of type SelectionSettings. Then set the Editor Attribute on your SelectionSettings property to your custom UITypeEditor derived class.
Here's a generic code example of how this would look:
using System;
using System.Drawing.Design;
using System.ComponentModel;
using System.Windows.Forms;
// ...
[Editor(typeof(SomeProperty_Editor), typeof(UITypeEditor))] // You might be able to place this attribute on class SomeType, but I haven't tried yet
public SomeType SomeProperty
{
get { /* stuff */ }
set { /* stuff */ } // optional, really
}
class SomeProperty_Editor : UITypeEditor
{
public override UITypeEditorEditStyle GetEditStyle(ITypeDescriptorContext context)
{
return UITypeEditorEditStyle.Modal;
}
public override object EditValue(ITypeDescriptorContext context, IServiceProvider provider, object value)
{
IWindowsFormsEditorService service = (IWindowsFormsEditorService)(provider.GetService(typeof(IWindowsFormsEditorService)));
SomeProperty_EditorWindow EditorWindow = new SomeProperty_EditorWindow(value as SomeType);
service.ShowDialog(EditorWindow);
if (EditorWindow.EditCancelled)
return value;
else
return EditorWindow.GetEdittedValue();
}
}
class SomeProperty_EditorWindow : Form
{
public SomeProperty_EditorWindow(SomeType CurrentProperty) : base()
{
InitializeComponents();
// Grab info in CurrentProperty here and display it on form
}
public void InitializeComponents()
{
// write yourself or use designer
}
public SomeType GetEdittedValue()
{
// return editted value from form components
}
public bool EditCancelled = false; // Set true if cancel button hit
}
You may want to look up the PropertyGrid Control as it could be very useful in your EditorWindow. Also, you can go to the UITypeEditor Class's MSDN page, look at all of the .NET derived classes under "Inheritance Hierarchy" to see if there is a built in editor that is close in functionality to what you want to do and inherit directly from that class.

MvvmCross - handle button click in viewmodel

I'm new to xamarin and mvvmcross and I would like to wire up a simple button click from my ios project to my viewmodel.
using System;
using MvvmCross.Binding.BindingContext;
using MvvmCross.iOS.Views;
using Colingual.Core.ViewModels;
namespace Colingual.iOS
{
public partial class LoginView : MvxViewController
{
public LoginView() : base("LoginView", null)
{
}
public override void ViewDidLoad()
{
base.ViewDidLoad();
// Perform any additional setup after loading the view, typically from a nib.
var set = this.CreateBindingSet<LoginView, LoginViewModel>();
set.Bind(Username).To(vm => vm.Username);
set.Bind(Password).To(vm => vm.Password);
set.Bind(btnLogin).To(vm => vm.MyAwesomeCommand);
set.Apply();
}
public override void DidReceiveMemoryWarning()
{
base.DidReceiveMemoryWarning();
// Release any cached data, images, etc that aren't in use.
}
}
}
I would like to wire up btnlogin to myawesomecommand.
using MvvmCross.Core.ViewModels;
namespace Colingual.Core.ViewModels
{
public class LoginViewModel : MvxViewModel
{
readonly IAuthenticationService _authenticationService;
public LoginViewModel(IAuthenticationService authenticationService)
{
_authenticationService = authenticationService;
}
string _username = string.Empty;
public string Username
{
get { return _username; }
set { SetProperty(ref _username, value); }
}
string _password = string.Empty;
public string Password
{
get { return _password; }
set { SetProperty(ref _password, value); }
}
public bool AuthenticateUser() {
return true;
}
MvxCommand _myAwesomeCommand;
public IMvxCommand MyAwesomeCommand
{
get
{
DoStuff();
return _myAwesomeCommand;
}
}
void DoStuff()
{
string test = string.Empty;
}
}
}
As you can see I've got mvxCommand with the name of MyAwesomecommand but I want to handle some logic from a button click in my other project. Anyone know what I should do?
I've done more looking around and found an answer here.
MvxCommand _myAwesomeCommand;
public IMvxCommand MyAwesomeCommand
{
get { return new MvxCommand(DoStuff); }
}
void DoStuff()
{
string test = string.Empty;
}
The idea is to have your mvxcommand getter which returns a new command that takes the method as a parameter.
When clicking the button btnLogin, you can access void DoStuff in viewmodel.

2 class inheritance NotifyPropertyChanged fails update UI

I have currently the problem that my UI doesnt update as I like to do so, hope you can help me out.
I have a simulated "2 class inheritance" as recommended in this page
http://www.codeproject.com/Articles/10072/Simulated-Multiple-Inheritance-Pattern-for-C
My real life app looks like the following:
public class Item : INotifyPropertyChanged
{
private bool _isVisible;
public bool IsVisible
{
get
{
return _isVisible;
}
set
{
if (_isVisible == value)
return;
_isVisible = value;
OnPropertyChanged("IsVisible");
}
}
//NotifyPropertyChanged Implementation removed so the focus stays on problem...
}
public class ObjectItem : INotifyPropertyChanged
{
private bool _isExpanded;
public bool IsExpanded
{
get
{
return _isExpanded;
}
set
{
if (_isExpanded== value)
return;
_isExpanded= value;
OnPropertyChanged("IsExpanded");
}
}
//NotifyPropertyChanged Implementation removed so the focus stays on problem...
}
public class CombinedItem : Item
{
private readonly ObjectItem _objectItem = new ObjectItem();
public bool IsExpanded
{
get { return _objectItem.IsExpanded; }
set { _objectItem.IsExpanded = value; }
}
public static implicit operator ObjectItem(CombinedItem combinedItem)
{
return combinedItem._objectItem;
}
}
I am now facing the problem that the Property IsExpanded doesnt get Notified to the UI correctly when I have a CominedItem as the DataContext, the IsVisible Property works as expected.
To overcome the problem I have changed the CominedItem to the following:
public class CombinedItem : Item
{
private readonly ObjectItem _objectItem = new ObjectItem();
public bool IsExpanded
{
get { return _objectItem.IsExpanded; }
set
{
if (_objectItem.IsExpanded == value)
return;
_objectItem.IsExpanded = value;
OnPropertyChanged("IsExpanded");
}
}
public static implicit operator ObjectItem(CombinedItem combinedItem)
{
return combinedItem._objectItem;
}
}
Is there a way to avoid writing the OnPropertyChanged("IsExpanded") again, with this approach.
(I know there are libaries/tools, where you dont need to write it at all and just have to declare a attribute, pls dont suggest those)
Actually you should subscribe to ObjectItem PropertyChanged and raise the matching event on CombinedItem.
If _objectItem.IsExpanded is modified without using CombinedItem.IsExpanded, your UI will not see the change.
Without some magic attribute/tool if you want to wrap a property, you will have to handle changes notification.
public class CombinedItem : Item
{
private readonly ObjectItem _objectItem = new ObjectItem();
public CombinedItem()
{
_objectItem.PropertyChanged += (s, e) =>
{
if (e.PropertyName == "IsExpanded")
OnPropertyChanged("IsExpanded");
}
}
public bool IsExpanded
{
get { return _objectItem.IsExpanded; }
set { _objectItem.IsExpanded = value; }
}
public static implicit operator ObjectItem(CombinedItem combinedItem)
{
return combinedItem._objectItem;
}
}
You could expose ObjectItem as a property and bind to that
public class CombinedItem : Item
{
private readonly ObjectItem _objectItem = new ObjectItem();
public bool IsExpanded
{
get { return _objectItem.IsExpanded; }
set { _objectItem.IsExpanded = value; }
}
public ObjectItem ObjectItem
{
get { return _objectItem; }
}
public static implicit operator ObjectItem(CombinedItem combinedItem)
{
return combinedItem._objectItem;
}
}
<Expander IsExpanded={Binding ObjectItem.IsExpanded}/>

Categories

Resources