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using System;
using System.ComponentModel;
using System.Windows;
using System.Windows.Threading;
namespace Pfz.WpfControls
{
/// <summary>
/// A control bound to a property of an object.
/// </summary>
/// <typeparam name="ObjectType">The type of the DataSource property.</typeparam>
public class PropertyBoundControl<ObjectType>:
PropertyBoundControlBase,
IDataSourceChangedHandler,
IIsReadOnlyChangedHandler
{
private ValueControl fValueControl = new ValueControl();
/// <summary>
/// Creates a new PropertyBoundControl instance.
/// </summary>
public PropertyBoundControl()
{
fValueControl.ValueChanged += p_ValueControl_ValueChanged;
fValueControl.ValueChangeThrownException += p_ValueControl_ValueChangeThrownException;
Content = fValueControl;
}
void p_ValueControl_ValueChangeThrownException(object sender, ValueExceptionEventArgs args)
{
args.RoutedEvent = ValueControl.ValueChangeThrownExceptionEvent;
RaiseEvent(args);
}
private void p_ValueControl_ValueChanged(object sender, ValueChangedEventArgs args)
{
OnValueChanged(args);
object value = Value;
var binding = fPropertyBinding;
if (binding == null)
return;
var property = binding.Property;
if (property == null)
return;
var dataSource = DataSource;
if (dataSource == null)
return;
if (p_IsReadOnly())
return;
property.SetValue(dataSource, value, null);
}
private PropertyBinding fPropertyBinding;
/// <summary>
/// Gets or sets the PropertyBinding of this control.
/// </summary>
public PropertyBinding PropertyBinding
{
get
{
return fPropertyBinding;
}
set
{
fPropertyBinding = value;
p_MustRecreate();
}
}
private bool fCanShowDisplayName = true;
/// <summary>
/// Gets or sets a value indicating is the DisplayName can be shown.
/// </summary>
[DefaultValue(true)]
public bool CanShowDisplayName
{
get
{
return fCanShowDisplayName;
}
set
{
if (value == fCanShowDisplayName)
return;
fCanShowDisplayName = value;
if (value)
{
var binding = fPropertyBinding;
if (binding == null)
fValueControl.DisplayName = null;
else
fValueControl.DisplayName = binding.ToString();
}
else
fValueControl.DisplayName = null;
}
}
/// <summary>
/// Gets or sets the object that is read/written as the data-source.
/// </summary>
public ObjectType DataSource
{
get
{
var result = BoundControl.GetDataSource(this);
if (!(result is ObjectType))
return default(ObjectType);
return (ObjectType)result;
}
set
{
BoundControl.SetDataSource(this, value);
}
}
/// <summary>
/// Gets or sets a value indicating if this control is/should-be read-only.
/// </summary>
public bool IsReadOnly
{
get
{
return BoundControl.GetIsReadOnly(this);
}
set
{
BoundControl.SetIsReadOnly(this, value);
}
}
/// <summary>
/// Gets or sets the value of this controls.
/// </summary>
public override object Value
{
get
{
return fValueControl.Value;
}
set
{
fValueControl.Value = value;
}
}
/// <summary>
/// Reads (refreshes) the value of the control from the data-source.
/// </summary>
public override void ReadFromDataSource()
{
var dataSource = DataSource;
if (dataSource == null)
{
fValueControl.Clear();
fValueControl.IsReadOnly = true;
return;
}
fValueControl.IsReadOnly = p_IsReadOnly();
fValueControl.Value = p_GetBoundValue();
}
private bool p_IsReadOnly()
{
var binding = fPropertyBinding;
if (binding == null)
return true;
var property = binding.Property;
if (property == null)
return true;
if (!property.CanWrite)
return true;
return IsReadOnly || BoundControl.IsDataSourceReadOnly(DataSource);
}
private object p_GetBoundValue()
{
var dataSource = DataSource;
if (dataSource == null)
return null;
var binding = fPropertyBinding;
if (binding == null)
return null;
var property = binding.Property;
if (property == null)
return null;
return property.GetValue(dataSource, null);
}
private bool fMustRecreate;
private void p_MustRecreate()
{
if (fMustRecreate)
return;
fMustRecreate = true;
Dispatcher.BeginInvoke(new Action(p_RecreateNow));
}
private void p_RecreateNow()
{
fMustRecreate = false;
var binding = fPropertyBinding;
if (binding == null)
{
fValueControl.DataType = null;
fValueControl.DisplayName = null;
return;
}
if (fCanShowDisplayName)
fValueControl.DisplayName = binding.ToString();
else
fValueControl.DisplayName = null;
var property = binding.Property;
if (property != null)
fValueControl.DataType = property.PropertyType;
ReadFromDataSource();
}
/// <summary>
/// Method invoked when the value of this control changes.
/// </summary>
protected virtual void OnValueChanged(ValueChangedEventArgs args)
{
args.RoutedEvent = ValueControl.ValueChangedEvent;
RaiseEvent(args);
}
/// <summary>
/// Event invoked when the value of this control changes.
/// </summary>
public event EventHandler<ValueChangedEventArgs> ValueChanged
{
add
{
AddHandler(ValueControl.ValueChangedEvent, value);
}
remove
{
RemoveHandler(ValueControl.ValueChangedEvent, value);
}
}
/// <summary>
/// Event invoked when an exception is thrown during the process of
/// ValueChange.
/// </summary>
public event EventHandler<ValueExceptionEventArgs> ValueChangeThrownException
{
add
{
AddHandler(ValueControl.ValueChangeThrownExceptionEvent, value);
}
remove
{
RemoveHandler(ValueControl.ValueChangeThrownExceptionEvent, value);
}
}
#region IDataSourceChangedHandler Members
void IDataSourceChangedHandler.OnDataSourceChanged(DependencyPropertyChangedEventArgs args)
{
if (!fMustRecreate)
ReadFromDataSource();
}
#endregion
#region IIsReadOnlyChangedHandler Members
void IIsReadOnlyChangedHandler.OnIsReadOnlyChanged(DependencyPropertyChangedEventArgs args)
{
fValueControl.IsReadOnly = p_IsReadOnly();
}
#endregion
}
/// <summary>
/// A property-bound control that uses the DataSource as a System.Object.
/// </summary>
public sealed class ObjectPropertyBoundControl:
PropertyBoundControl<object>
{
}
}
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I started to program computers when I was 11 years old, as a hobbyist, programming in AMOS Basic and Blitz Basic for Amiga.
At 12 I had my first try with assembler, but it was too difficult at the time. Then, in the same year, I learned C and, after learning C, I was finally able to learn assembler (for Motorola 680x0).
Not sure, but probably between 12 and 13, I started to learn C++. I always programmed "in an object oriented way", but using function pointers instead of virtual methods.
At 15 I started to learn Pascal at school and to use Delphi. At 16 I started my first internship (using Delphi). At 18 I started to work professionally using C++ and since then I've developed my programming skills as a professional developer in C++ and C#, generally creating libraries that help other developers do their work easier, faster and with less errors.
Want more info or simply want to contact me?
Take a look at:
http://paulozemek.azurewebsites.net/
Or e-mail me at: paulozemek@outlook.com
Codeproject MVP 2012, 2015 & 2016
Microsoft MVP 2013-2014 (in October 2014 I started working at Microsoft, so I can't be a Microsoft MVP anymore).