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Bind a Converter Parameter in re-usable User Control

I am trying to create a re-usable user control (for data entry) in which there are two text boxes and they are linked to each by an IValueConvertor.
The following XAML is the original, normal code. This is what I am trying to reproduce in a user control.
<WrapPanel>
<TextBlock Text="Length of Fence"/>
<TextBox Name="Metric" Width="50" Text="{Binding Path=LengthFence, Mode=TwoWay}"/>
<TextBlock Text="Meters"/>
<TextBox Text="{Binding ElementName=Metric, Path=Text, Converter={StaticResource MetersToInches}, StringFormat=N8}"/>
<TextBlock Text="Inches"/>
</WrapPanel>
and the code-behind for the IValueConvertor (in MainWindow.xaml) is
public class MetersToInches : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
if (value.ToString() == "")
return 0.0;
try
{
double meters = System.Convert.ToDouble(value);
var result = meters * 39.3701;
return result;
}
catch
{
// Catch errors when users type invalid expressions.
return 0.0;
}
}
public object ConvertBack(object value, Type targettype, object parameter, CultureInfo culture)
{
if (value.ToString() == "")
return 0.0;
try
{
double inches = System.Convert.ToDouble(value);
var result = inches * 0.0254;
return result;
}
catch
{
// Catch errors when users type invalid expressions.
return 0.0;
}
}
}
This is what this XAML looks like:
Now I have made a re-usable UserControl with three dependency properties Label for label string, Value for binding a property inside the ViewModel, and Units - a string property to show the input units.
<UserControl ...
x:Name="parent">
<StackPanel DataContext="{Binding ElementName=parent}">
<TextBlock Text="{Binding Path=Label}"/>
<TextBox Text="{Binding Path=Value}"/>
<TextBlock Text="{Binding Path=Units}"/>
</StackPanel>
However, this re-usable control can only tackle the first TextBox of the input. I do not know how to bind the IValueConvertor in the second TextBox. I need to do this because I want to bind other converters such as meters to feet, kg to pound, etc.
I have read that ConvertorParameter cannot be bound because it is not a dependency property and I am not sure if I can use multi-binding, mostly because I do not know how to use it properly Binding ConverterParameter.
I would be very grateful if you could show me how to do this or direct me to the appropriate link on StackOverflow or elsewhere that solves this problem. Or if there is a better way of doing this.
Many many thanks in advance.

First, don't bind the TextBoxes to each other (as in your original code at the begining of the question), instead, bind each TextBox to the same backing property, which, in your UserControl, is Value.
As for how to implement multiple bindings, you probably don't need a MultiBinding.
We have to pick a "standard" unit of measure to begin with- this will be the unit that will be actually stored in the property and in any database or file. I'll assume this standard unit will be meters (m). An IValueConverter can be used to convert between meters and some other unit of distance and back, using the ConverterParameter to specify which other unit to convert to/from.
Here's a good example to get you started.
public enum DistanceUnit { Meter, Foot, Inch, }
public class DistanceUnitConverter : IValueConverter
{
private static Dictionary<DistanceUnit, double> conversions = new Dictionary<DistanceUnit, double>
{
{ DistanceUnit.Meter, 1 },
{ DistanceUnit.Foot, 3.28084 },
{ DistanceUnit.Inch, 39.37008 }
};
//Converts a meter into another unit
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
return conversions[(DistanceUnit)parameter] * (double)value;
}
//Converts some unit into a meter
public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
if (value == null) { return 0; }
double v;
var s = value as string;
if (s == null)
{
v = (double)value;
}
else
{
if (s == string.Empty) { return 0; }
v = double.Parse(s);
}
if (v == 0) { return 0; }
return v / conversions[((DistanceUnit)parameter)];
}
}
The above has a few problems. I never check if parameter really is a DistanceUnit before using it, for example. But it works.
Here's an example of how I used it:
<StackPanel>
<StackPanel.Resources>
<local:DistanceUnitConverter x:Key="DistCon"/>
</StackPanel.Resources>
<StackPanel Orientation="Horizontal">
<TextBox Text="{Binding Distance, Converter={StaticResource DistCon}, ConverterParameter={x:Static local:DistanceUnit.Meter}}" MinWidth="20"/>
<TextBlock>m</TextBlock>
</StackPanel>
<StackPanel Orientation="Horizontal">
<TextBox Text="{Binding Distance, Converter={StaticResource DistCon}, ConverterParameter={x:Static local:DistanceUnit.Foot}}" MinWidth="20"/>
<TextBlock>ft</TextBlock>
</StackPanel>
</StackPanel>
The DistanceUnit enum and the internal conversions dictionary can be expanded with more units of measure. Alternatively, you can use a 3rd party library that already has all these included, like UnitsNet.

Not sure how you would like to bind mulitple converters in one single control. If i'm not wrong, you would like to build a control where when a user enters a particular value, you need to display it in different units. If this is the case, you can create a single converter with converterparameter as "m","cm","inch" etc and based on this you can return the result. Then in this case, you will have 4,5 controls and each will have same converter binding but different converter values. If this is not clear and you need further direction, please let know.
Multi Value binding
To answer your point 6, please see a sample multi binding converter and its implementation in xaml below. I have built a simple RolesFilter which will take different inputs from the xaml as object[] and since I already know what data is expected, i'm converting them in the converter.
public class RolesFilter : IMultiValueConverter
{
public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
{
try
{
FlipperObservableCollection<Role> _roles = (FlipperObservableCollection<Role>)values[0]; //Input
Department _dept_param = values[1] as Department;
bool _filter = (bool)values[2];
string _id = "NA";
if (values.Count() == 4 && values[3] is string) _id = (string)values[3] ?? "NA";
//If we need a filter, then without department, it should return empty results
if (!_filter) return _roles; //If no filter is required, then don't worry, go ahead with input values.
if (_dept_param == null) return new FlipperObservableCollection<Role>(); //If department is null, then
List<Role> _filtered_list = _roles.ToList().Where(p => p.department.id == _dept_param.id && p.id != _id)?.ToList() ?? new List<Role>();
return new FlipperObservableCollection<Role>(_filtered_list);
}
catch (Exception)
{
throw;
}
}
public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)
{
throw new NotImplementedException();
}
}
I'm using the multi value converter in the xaml as below. Here, i'm filtering an itemsource of a combo box based on another combobox and a check box. This is just an example and in your case, you can create a combo box with different Units values. Based on user selection, you can use the converter and return value to the textbox.
<ComboBox Height="30" SelectedItem="{Binding reports_to, NotifyOnTargetUpdated=True, NotifyOnSourceUpdated=True, UpdateSourceTrigger=PropertyChanged}">
<ComboBox.ItemsSource>
<MultiBinding Converter="{StaticResource roles_filter}">
<Binding Source="{StaticResource SingletonData__}" Path="roles" NotifyOnSourceUpdated="True" UpdateSourceTrigger="PropertyChanged"/>
<Binding Path="department" NotifyOnSourceUpdated="True" UpdateSourceTrigger="PropertyChanged"/>
<Binding ElementName="cbx_filter" Path="IsChecked"/>
<Binding Path="id" NotifyOnSourceUpdated="True" UpdateSourceTrigger="PropertyChanged"/>
</MultiBinding>
</ComboBox.ItemsSource>
<ComboBox.ItemTemplate>
<DataTemplate>
<WrapPanel>
<TextBlock Text="{Binding department.name}"/>
<TextBlock Text=" - "/>
<TextBlock Text="{Binding name}"/>
</WrapPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>

C# Wpf Binding type adapter

As of now, i assign the image of a TreeView item using a direct binding to the image's source:
<DataTemplate DataType="{x:Type local:GeoPoint}">
<StackPanel Orientation="Horizontal">
<Image Source="{Binding Color}" Height="32" />
<TextBlock Text="{Binding Name}" VerticalAlignment="Center"/>
</StackPanel>
</DataTemplate>
the Color binding is referring to string containing the path to the PNG, something like "/Resources/red.png"
i would like to make the Color variable of custom type "MarkerColor", an enum containing several colors, and have the image source binding reference this value, so that if
Color = MarkerColor.green; the binding would reference "/Resources/green.png"
Note that the name of the PNG is not necessarily the same as the name of MarkerColor, an "adapter" should be used to convert the type
I know how to do this in Java Android SDK, but not really sure on how to achive this in Wpf

You could create a converter that knows how to convert the enumeration value to a valid resource:
public class ColorResourceConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
MarkerColor color = (MarkerColor)value;
Uri uri;
switch(color)
{
case MarkerColor.Green:
uri = new Uri("Resources/green.png");
break;
case MarkerColor.Red:
uri = new Uri("Resources/red.png");
break;
//...
default:
uri = new Uri("Resources/default.png");
break;
}
return new BitmapImage(uri);
}
public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
throw new NotSupportedException();
}
}
Usage:
<DataTemplate DataType="{x:Type local:GeoPoint}">
<DataTemplate.Resources>
<local:ColorResourceConverter x:Key="ColorResourceConverter" />
</DataTemplate.Resources>
<StackPanel Orientation="Horizontal">
<Image Source="{Binding Color, Converter={StaticResource ColorResourceConverter}}" Height="32" />
<TextBlock Text="{Binding Name}" VerticalAlignment="Center"/>
</StackPanel>
</DataTemplate>

Set the content of Label to Image's Tooltip

I am using IValueconverter interface to change the tooltip text of an image.
The tool tip should change based on label.
<Label Content="9898980001" Height="28" HorizontalAlignment="Left" Margin="1733,231,0,0" Name="lbl02scanning" VerticalAlignment="Top" Foreground="Blue" >
<Image Height="49" HorizontalAlignment="Right" Margin="0,131,113,0"
Name="img02scanning"
Source="/TEST;component/Images/LoadingStation.png" Stretch="Fill"
VerticalAlignment="Top" Width="30" Cursor="Hand">
<Image.ToolTip>
<StackPanel Background="AliceBlue">
<TextBlock Padding="5" Foreground="White" MinHeight="20"
Background="Blue" FontWeight="Bold"
Text="Scanning Station" />
<StackPanel Orientation="Horizontal">
<Image
Source="pack://application:,,,/TEST;component/Images/coilonsaddle_large.png"
Height="100" Width="100" />
<TextBlock Padding="10" TextWrapping="WrapWithOverflow"
MaxWidth="200" Background="AliceBlue"
Foreground="Black" FontWeight="Bold"
Text="{Binding ElementName=lbl02scanning, Path=Name,
ConverterParameter=255,
Converter={StaticResource FormatterFOrCoilToolTip}}"/>
</StackPanel>
<TextBlock Padding="5" Foreground="White" MinHeight="20"
Background="Blue" FontWeight="Bold"
Text="Report to admin in case of coil location mismatch"/>
</StackPanel>
</Image.ToolTip>
</Image>
The converter class:
public class FormatterForCoilToolTip : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
if(parameter.ToString() == "02")
{
return value.ToString() + " Startin";
}
else
{
return value.ToString() + " Finishing";
}
}
}
public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
throw new NotImplementedException();
}
}
The tooltip's Textblock content is not changing. But if i change to:
Text="{Binding ConverterParameter=255, Converter={StaticResource FormatterFOrCoilToolTip}}
then it is working. But i want to pass the lbl02scanning text value. Why it is not working??

First of all you should bind to Content property and not Name property in case you want Text of Label.
Most importantly Tooltip does not lies in same Visual Tree as that of label, hence binding with elementName won't work. However, you can use x:Reference to get the element even if it doesn't exist in same Visual Tree.
Text="{Binding Source={x:Reference lbl02scanning}, Path=Content,
ConverterParameter=255,
Converter={StaticResource FormatterFOrCoilToolTip}}"/>
Note - x:Reference is introduced in WPF 4.0. If you are using WPF 3.5 you can't use this.
Update for error - service provider is missing the name resolver service
Just found out bug is reported at Microsoft site that x:Reference fails in case Target is Label. However, i couldn't reproduce this issue at my end since i have WPF 4.5 installed at my end and i guess they have fixed the issue in future version.
In case you target WPF 4.0, i would advise you to use TextBlock in place of Label:
<TextBlock Text="9898980001" Height="28" HorizontalAlignment="Left"
Margin="1733,231,0,0" Name="lbl02scanning" VerticalAlignment="Top"
Foreground="Blue" />
and then bind with Text property instead of Content.
Text="{Binding Source={x:Reference lbl02scanning}, Path=Text,
ConverterParameter=255,
Converter={StaticResource FormatterFOrCoilToolTip}}"/>
Either, you can refer to workaround provide under workarounds section here.
You can override the ProvideValue method of the Reference class and skip the reference search login in design time:
[ContentProperty("Name")]
public class Reference : System.Windows.Markup.Reference
{
public Reference()
: base()
{ }
public Reference(string name)
: base(name)
{ }
public override object ProvideValue(IServiceProvider serviceProvider)
{
IProvideValueTarget valueTargetProvider = serviceProvider.GetService(typeof(IProvideValueTarget)) as IProvideValueTarget;
if (valueTargetProvider != null)
{
DependencyObject targetObject = valueTargetProvider.TargetObject as DependencyObject;
if (targetObject != null && DesignerProperties.GetIsInDesignMode(targetObject))
{
return null;
}
}
return base.ProvideValue(serviceProvider);
}
Update with another workaround
This will work for all versions WPF 3.5, WPf 4.0 and WPF 4.5.
First of all bind Image Tag with content of label.
Second host your stackPanel inside ToolTip control so that you can
take benefit of PlacementTarget property.
Third bind with PlacementTarget.Tag of Tooltip.
Relevant code will look like this:
<Image Tag="{Binding ElementName=lbl02scanning,Path=Content}">
<Image.ToolTip>
<ToolTip>
<TextBlock Text="{Binding RelativeSource={RelativeSource
Mode=FindAncestor, AncestorType=ToolTip},
Path=PlacementTarget.Tag,
ConverterParameter=255,
Converter={StaticResource FormatterFOrCoilToolTip}}"/>
</ToolTip>
</Image.ToolTip>
</Image>
Also you need to update converter code to put null check over there since PlacementTarget will be null until you open tooltip.
public object Convert(object value, Type targetType,
object parameter, CultureInfo culture)
{
if (value != null)
{
if (parameter.ToString() == "02")
{
return value.ToString() + " Starting";
}
else
{
return value.ToString() + " Finishing";
}
}
return String.Empty;
}

Try This
Text="{Binding Path=Content,ElementName=lbl02scanning, ConverterParameter=255, Converter={StaticResource FormatterFOrCoilToolTip}}

Unable to apply string formatting in Silverlight DataGrid column

I have a Data Grid. Its Item source is set to a List. My problem is that Iam unable to apply string formatting . This is formats Ive tried . Am I missing some thing ?
StringFormat='MM/dd/yyyy'
StringFormat={0:dd-MMM-yyyy}
Attached the resultant grid
<sdk:DataGridTemplateColumn Header="Recieved Date" Width="Auto" >
<sdk:DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<TextBlock Text="{Binding Path=RecievedDate, StringFormat=\{0:dd-MMM-yyyy\} }" />
</DataTemplate>
</sdk:DataGridTemplateColumn.CellTemplate>
<sdk:DataGridTemplateColumn.CellEditingTemplate>
<DataTemplate>
<sdk:DatePicker Name="dtpFinancialAndComplianceLog" Text="{Binding Path=RecievedDate,Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />
</DataTemplate>
</sdk:DataGridTemplateColumn.CellEditingTemplate>
</sdk:DataGridTemplateColumn>

If I understand what you're trying to do correctly, you have a DataGrid column which you want to display a DateTime object in a certain format. Ordinarily a DateTime object will sort out its own formatting depending on the System.Threading.Thread.CurrentUICulture.
Easiest way I know of to force any object into a certain format is to use a custom IValueConverter:
namespace MyProject.Converters
{
public class FormatConverter : IValueConverter
{//Suitable only for read-only data
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
if (value == null)
return string.Empty;
if(string.IsNullOrEmpty(parameter.ToString()))
return value.ToString();
return string.Format(culture, parameter.ToString(), value);
}
public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
return null;
}
}
}
After adding a namespace to your xaml: xmlns:conv="clr-namespace:MyProject.Converters" and declaring your converter in the control's resources <conv:FormatConverter x:Key="Formatter" />, you will need to bind your column's data using your new converter:
<TextBlock Text="{Binding Path=RecievedDate, Converter={StaticResource Formatter}, ConverterParameter=\{0:dd-MMM-yyy\} }" />

TextBlock as big as a capital letter (ignoring font ascender/descender)

I am looking to get a specific behavior on TextBlock so that its height only includes the height of the capital letters (from baseline to top minus "ascender height"). Please see the image Sphinx from Wikipedia to see what I mean. Also the image below may indicate better what I am after.
I am not specifically looking for a pure XAML solution (probably impossible) so a C# code behind (a converter) is also fine.
This is the XAML used in XamlPad to produce the left A in the image above.
<TextBlock Text="A" Background="Aquamarine" FontSize="120" HorizontalAlignment="Center" VerticalAlignment="Center" />

u can try to use attribute LineStackingStrategy="BlockLineHeight" and a Converter on the LineHeight attributes and a converter on the Height of TextBlock.
This a sample code of converters
// Height Converter
public class FontSizeToHeightConverter : IValueConverter
{
public static double COEFF = 0.715;
public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
return (double)value * COEFF;
}
public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
throw new NotImplementedException();
}
}
// LineHeightConverter
public class FontSizeToLineHeightConverter : IValueConverter
{
public static double COEFF = 0.875;
public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
return double.Parse(value.ToString()) * COEFF;
}
public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
throw new NotImplementedException();
}
}
The Coefficient used on converters depends on Used Family Fonts (Baseline and LineSpacing):
<TextBlock Text="ABC" Background="Aqua" LineStackingStrategy="BlockLineHeight"
FontSize="{Binding ElementName=textBox1, Path=Text}"
FontFamily="{Binding ElementName=listFonts, Path=SelectedItem}"
Height="{Binding RelativeSource={RelativeSource Self}, Path=FontSize, Mode=OneWay, Converter={StaticResource FontSizeToHeightConverter1}}"
LineHeight="{Binding RelativeSource={RelativeSource Self}, Path=FontSize, Converter={StaticResource FontSizeToLineHeightConverter}}"/>
The best solution is to find how to calculate the Coeff based on parameters Baseline and LineSpacing of the FontFamily.
In this sample (Segeo UI) the Coeff of Height = 0.715 and LineHeight = 0,875 * FontSize.

Updated:
If I understand right, there's a few tricks I know for this,
You can Scale it with RenderTransform which is usually the most efficient way;
<TextBlock Text="Blah">
<TextBlock.RenderTransform>
<CompositeTransform ScaleY="3"/>
</TextBlock.RenderTransform>
</TextBlock>
Or you can embed the TextBlock in a Viewbox to "zoom" the text to fit the bounds of its container if for example you set hard height values on grid rows like;
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="120"/>
<RowDefinition Height="120"/>
</Grid.RowDefinitions>
<Viewbox VerticalAlignment="Stretch" Height="Auto">
<!-- The textblock and its contents are
stretched to fill its parent -->
<TextBlock Text="Sphinx" />
</Viewbox>
<Viewbox Grid.Row="2" VerticalAlignment="Stretch" Height="Auto">
<!-- The textblock and its contents are
stretched to fill its parent -->
<TextBlock Text="Sphinx2" />
</Viewbox>
or you can bind the FontSize to a Container element like;
<Grid x:Name="MyText" Height="120">
<TextBlock FontSize="{Binding ElementName=MyText, Path=Height}" Text="Sphinx" />
</Grid>
They might present the effect you're after?