A Context-Sensitive Help Provider in Wpf

WPF Articles

Rudi Grobler — Sun, 29 Jul 2007 17:28:39 GMT

Dr Tim Sneath gives a overview of what is new in WPF 3.5 http://blogs.msdn.com/tims/archive/2007/07/27

re: A Context-Sensitive Help Provider in Wpf

andemann — Tue, 14 Aug 2007 10:32:31 GMT

Any ideas on how to make this appear based on mouseover and not just focus?

Attempting to create office 2007 style super tooltips with the F1 for more help.

Andreas

re: A Context-Sensitive Help Provider in Wpf

andemann — Wed, 15 Aug 2007 10:17:25 GMT

I found the answer. Use CommandBinding in the custom toolTip contructor.

Andreas

re: A Context-Sensitive Help Provider in Wpf

black_nm — Fri, 31 Aug 2007 12:21:45 GMT

I've created a full code for HelpProvider:

using System.Windows;

using System.Windows.Forms;

using System.Windows.Input;

using System.Windows.Media;

namespace Diginesis.Presentation.Controls

{

public static class DiginesisHelpProvider

{

#region Fields

private static string mHelpNamespace = null;

private static bool mShowHelp = false;

private static string mNotFoundTopic;

public static readonly DependencyProperty HelpKeywordProperty =

DependencyProperty.RegisterAttached("HelpKeyword", typeof (string), typeof (DiginesisHelpProvider));

public static readonly DependencyProperty HelpNavigatorProperty =

DependencyProperty.RegisterAttached("HelpNavigator", typeof (HelpNavigator), typeof (DiginesisHelpProvider),

new PropertyMetadata(HelpNavigator.TableOfContents));

public static readonly DependencyProperty ShowHelpProperty =

DependencyProperty.RegisterAttached("ShowHelp", typeof (bool), typeof (DiginesisHelpProvider));

#endregion

#region Constructors

static DiginesisHelpProvider()

{

CommandManager.RegisterClassCommandBinding(

typeof (FrameworkElement),

new CommandBinding(ApplicationCommands.Help, OnHelpExecuted, OnHelpCanExecute));

}

#endregion

#region Public Properties

public static string HelpNamespace

{

get { return mHelpNamespace; }

set { mHelpNamespace = value; }

}

public static bool ShowHelp

{

get { return mShowHelp; }

set { mShowHelp = value; }

}

public static string NotFoundTopic

{

get { return mNotFoundTopic; }

set { mNotFoundTopic = value; }

}

#endregion

#region Public Methods

#region HelpKeyword

public static string GetHelpKeyword(DependencyObject obj)

{

return (string) obj.GetValue(HelpKeywordProperty);

}

public static void SetHelpKeyword(DependencyObject obj, string value)

{

obj.SetValue(HelpKeywordProperty, value);

}

#endregion

#region HelpNavigator

public static HelpNavigator GetHelpNavigator(DependencyObject obj)

{

return (HelpNavigator) obj.GetValue(HelpNavigatorProperty);

}

public static void SetHelpNavigator(DependencyObject obj, HelpNavigator value)

{

obj.SetValue(HelpNavigatorProperty, value);

}

#endregion

#region ShowHelp

public static bool GetShowHelp(DependencyObject obj)

{

return (bool) obj.GetValue(ShowHelpProperty);

}

public static void SetShowHelp(DependencyObject obj, bool value)

{

obj.SetValue(ShowHelpProperty, value);

}

#endregion

#region Private Members

private static void OnHelpCanExecute(object sender, CanExecuteRoutedEventArgs e)

{

e.CanExecute = CanExecuteHelp((DependencyObject) sender) || ShowHelp;

}

private static bool CanExecuteHelp(DependencyObject sender)

{

if (sender != null)

{

if (GetShowHelp(sender))

return true;

return CanExecuteHelp(VisualTreeHelper.GetParent(sender));

}

return false;

}

private static DependencyObject GetHelp(DependencyObject sender)

{

if (sender != null)

{

if (GetShowHelp(sender))

return sender;

return GetHelp(VisualTreeHelper.GetParent(sender));

}

return null;

}

private static void OnHelpExecuted(object sender, ExecutedRoutedEventArgs e)

{

DependencyObject ctl = GetHelp(sender as DependencyObject);

if (ctl != null && GetShowHelp(ctl))

{

string parameter = GetHelpKeyword(ctl);

HelpNavigator command = GetHelpNavigator(ctl);

if (!e.Handled && !string.IsNullOrEmpty(HelpNamespace))

{

if (!string.IsNullOrEmpty(parameter))

{

Help.ShowHelp(null, HelpNamespace, command, parameter);

e.Handled = true;

}

if (!e.Handled)

{

Help.ShowHelp(null, HelpNamespace, command);

e.Handled = true;

}

if (!e.Handled && !string.IsNullOrEmpty(HelpNamespace))

{

Help.ShowHelp(null, HelpNamespace);

e.Handled = true;

}

else if (ShowHelp)

{

if (!string.IsNullOrEmpty(NotFoundTopic))

Help.ShowHelp(null, HelpNamespace, NotFoundTopic);

else

Help.ShowHelp(null, HelpNamespace);

e.Handled = true;

}

#endregion

}

re: A Context-Sensitive Help Provider in Wpf

black_nm — Fri, 31 Aug 2007 12:24:09 GMT

How to use it!?!?!

Add this to the App startup or constructor

DiginesisHelpProvider.HelpNamespace = "Help.chm";

DiginesisHelpProvider.ShowHelp = true;

And set on a control the properties:

c:DiginesisHelpProvider.ShowHelp="True"

c:DiginesisHelpProvider.HelpKeyword="HelpTest2.htm"

c:DiginesisHelpProvider.HelpNavigator="Topic"

WPF/Silverlight/XAML Web Links - 2004/04/18

Rob Relyea - Xamlified — Sat, 19 Apr 2008 06:35:37 GMT

  WPF Apps Jaime Rodriguez's list of WPF in Line-of-Business case studies CodePlex Project:

WPF/Silverlight/XAML Web Links - 2008/04/18

Rob Relyea - Xamlified — Sat, 19 Apr 2008 07:01:32 GMT

WPF Apps Jaime Rodriguez's list of WPF in Line-of-Business case studies CodePlex Project: Slick Code

clr-namespace:ContextSensitiveHelp not available

kyawtun4biz — Wed, 28 May 2008 15:24:35 GMT

clr-namespace:ContextSensitiveHelp not available in my WPF project.

Do I need to added some reference assembly?

re: clr-namespace:ContextSensitiveHelp not available

MikeHillberg — Fri, 30 May 2008 03:06:58 GMT

Sorry, ContextSensitiveHelp is the namespace that the HelpProvider class lives in. E.g.

namespace ContextSensitiveHelp

{

static class HelpProvider

{

...

}

How to provide a context sentitive help to your WPF application

NicolBlog — Tue, 10 Jun 2008 15:17:05 GMT

I found thie following interesting post where is well described how to provide your windows presentation

re: A Context-Sensitive Help Provider in Wpf

nightwriter — Wed, 13 May 2009 11:15:17 GMT

I think something's missing from the first example and the below would help it work.

<TextBox.CommandBindings><CommandBinding Command='ApplicationCommands.Help' Executed='Window_Help_Executed' /></TextBox.CommandBindings>

[[This is covered by the addition of the CommandBinding in the second example -Mike]]

re: A Context-Sensitive Help Provider in Wpf

tigerprawn — Fri, 14 Aug 2009 01:31:27 GMT

Hi Mike (or anyone that can help),

I have to implement context-sensitive help using WPF for a new project I'm involved with at work and your code looks a perfect solution.

However I spotted something when I was stepping through the code in debug. When the 'HelpStringProperty' dependency property is created and after the command binding is created in the constructor, if you then drill down to inspect the various attributes of the property, it seems to throw InvalidOperationExceptions against both 'OwnerType' and 'PropertyType' with the message 'Method may only be called on a type for which Type.IsGenericParameters is true'.

The code works fine even with the exceptions, but I'd like to understand why this is happening and try and resolve it if possible.

Hope this all makes sense!

Regards,

Neil