WPF Discussion Boards

WPF ListView scrollable height

9-May-10 19:25

datahead wrote:
Is there a class in the .net libraries that will do this for me? If not, does anyone know of a robust library I could download that already has this functionality?

I had faced the same problem and could not find a solution on the internet.
My database returns 01/01/01 as the null date and .Net's TryParse converts it to 01/01/2001 which is a valid date. The fixed that I finally implemented was to add an additional if condition to check 01/01/01 and treat such a date as null.

The minimum default year is specified in the Control Panel's regional settings option. In XP or Vista I was unable to change this date - not sure about Windows 7.

astibich27-May-10 11:28

astibich2

7-May-10 11:28

I am using the WPF ListView, with an embedded GridView, to display a table of data. When the scroll bar is present, I would like to slightly increase the scrollable height of the list, making a little more visible white space at the end of the list.

Note, I do NOT want to accomplish this by adding additional empty rows to the list.

Any ideas on how to accomplish this?

Thanks,

Aaron Stibich

Re: WPF ListView scrollable height

Leung Yat Chun8-May-10 23:13

Leung Yat Chun

8-May-10 23:13

There may be better method, but I think this should work :

You can create a ListViewItem template, so when it's last item (specify in your underlying model, or use TemplateSelector), occupy more space but not focusable.

Something like the following :

<DataTemplate x:Key="NormalColumn1Template" >
  <TextBlock Text="{Binding Text}" />
</DataTemplate>

<DataTemplate x:Key="LastColumn1Template" >
  <StackPanel Orientation="Vertical">
    <TextBlock Text="{Binding Text}" />
    <TextBlock Text="FreeSpace" Height="100" IsHitTestVisible="False" IsFocusable="False" Background="White" />
  </StackPanel>
</DataTemplate>

Regards
Joseph Leung

QuickZip

Expression Web....Not sure if this is the right place to post.

programmervb.netc++6-May-10 21:24

programmervb.netc++

6-May-10 21:24

I use componentone controls I have the newest/greatest version for VS2010. I am wondering why I cannot add the controls to the toolbox in Expression web I have installed them to the GAC with no luck has anyone else seen this?
Thanks,

Humble Programmer

Re: Expression Web....Not sure if this is the right place to post.

#realJSOP9-May-10 1:19

Re: Expression Web....Not sure if this is the right place to post.

9-May-10 1:19

I just went through the menus looking for the Visual Studio functionality that lets you refresh the toolbox, and it ain't there. It seems to me that if it's in the GAC, it should be in the toolbox. Have you tried Microsoft's Expression forums?

BTW, if they're silverlight controls, I'm pretty sure you need to use Expression Blend (or Visual Studio) to use them.

.45 ACP - because shooting twice is just silly
-----
"Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass..." - Dale Earnhardt, 1997
-----
"The staggering layers of obscenity in your statement make it a work of art on so many levels." - J. Jystad, 2001

#realJSOP12-May-10 2:09

Pass params to web service [SOLVED (but it ain't pretty)]

12-May-10 2:09

Put a space character somewhere in your user ID. The way it is now hoses up the column in the forum thread list.

#realJSOP6-May-10 9:16

6-May-10 9:16

I have a asp.net web service (as opposed to a WCF service), and I'm trying to pass a list to one of the methods from a silverlight app.

The object in the list is defined in it's own assembly, and the assembly is referenced by both the silverlight app and the web service:

public class FMSqlParameter 
{
    public string Key;
    public object Value;
}

public FMSqlParamContainer
{
    public FMSqlParameter[] array;
}

The reason I have to do that is because Silverlight doesn't allow you to use the Data namespace objects like SqlParameter. So I used the container as follows:

List<FmSqlParameter> parameters = new List<FmSqlParameter>;
parameters.Add(new FMSqlParameter("@name", 1);
FMSqlParamContainer container = new FMSqlParamContainer();
container.array = parameters.ToArray();

I have to do this because a web service method can't accept a generic collection. When I try to pass the container to the web service, I get the following error:

There was an error while trying to serialize parameter http://USAF_FM_Dashboard.org/:GetMetricData. The InnerException message was 'Type 'FMSharedLib.FMSqlParamContainer' with data contract name 'FMSqlParamContainer:http://schemas.datacontract.org/2004/07/FMSharedLib' is not expected. Add any types not known statically to the list of known types - for example, by using the KnownTypeAttribute attribute or by adding them to the list of known types passed to DataContractSerializer.'.  Please see InnerException for more details.

Can ayone help?

SOLUTION ======================

After trying about a dozen different ways to get this to work, I finally came up with a workaround, but it ain't pretty. I absolutely need the ability to pass a various number of different typs of parameters for the stored procedures. After dickin' around with generic lists, and casting to arrays of objects and not getting any of that to work, I've decided to pass the web service method an xml string and translate it to SqlParameters like so:

//-------------------------------------------------------------------------------------
private Parameters MakeSqlParameters(string xmlData)
{
	XDocument  xDoc       = XDocument.Parse(xmlData);
	XElement   root       = xDoc.Element("Parameters");
	Parameters parameters = null;
	if (root.HasElements)
	{
		parameters = new Parameters();
		IEnumerable<XElement> children = (from item in root.Elements() select item);
		foreach (XElement value in children)
		{
			string paramName       = value.Element("Name").Value;
			string typeName        = value.Element("Type").Value;
			object obj             = Convert.ChangeType(value.Element("Value").Value, 
                                                                    Type.GetType(typeName));
			SqlParameter parameter = new SqlParameter(paramName, obj);
			parameters.Add(parameter);
		}
	}
	return parameters;
}

On the client side, I created a static method that created an appropriate XElement:

//--------------------------------------------------------------------------------
public static XElement MakeXmlParameter(string name, object value)
{
	XElement element = new XElement("Parameter",
					 new XElement("Name", "@pivot"),
					 new XElement("Type", value.GetType()),
					 new XElement("Value", value));
	return element;
}

It all works great now.

modified on Friday, May 7, 2010 11:32 AM

Not Active6-May-10 9:44

Not Active

6-May-10 9:44

What does FMSqlParamContainer look like? It may be obvious but you have applied the Serializeable attribute correct?

I know the language. I've read a book. - _Madmatt

#realJSOP6-May-10 10:54

6-May-10 10:54

That's one of the many things silverlight doesn't appear to support (or maybe I'm thinking xml serialization)... :/

#realJSOP7-May-10 5:33

7-May-10 5:33

I posted my solution...

Not Active7-May-10 7:01

Not Active

7-May-10 7:01

You're right, it isn't pretty. I'd try a different shade of green Poke tongue | ;-P

Thanks for posting it

I know the language. I've read a book. - _Madmatt

Abhinav S7-May-10 0:23

7-May-10 0:23

For starters, you can have a look here. This article pretty much explains why we need KnownTypeAttribute.

AFAIK, you can use XmlSerializer in Silverlight (and the Serialize atrribute) although I have not tried it myself.

For this you need to use the SlSvcUtil tool when you are building the web service proxy.
You can then specify your parameters just like the the normal svcUtil tool.

None of my posts might solve your problem, since you are using asmx but I'm trying anyway.

#realJSOP7-May-10 1:52

7-May-10 1:52

Serialize isn't in Silverlight. I have to use DataContract. I'm working through it now. Thanks for the link

#realJSOP7-May-10 5:33

7-May-10 5:33

I posted the solution I came up with...

Abhinav S7-May-10 6:32

WPF UserControl design question

7-May-10 6:32

John Simmons / outlaw programmer wrote:
I posted the solution I came up with...

Thanks for posting the solution - as you mentioned it isnt neat - but it works and thats what matters.

Alex Barry6-May-10 5:38

Alex Barry

6-May-10 5:38

I am designing a WPF UserControl, and I'm not sure how to do part of it correctly. The main control to be consumed by the user will have three "sub-controls", that is controls that the main control composes to create the whole:

public class MainControl : UserControl {
public SubControl Sub1 {get; private set;}
public SubControl Sub2 {get; private set;}
public SubControl Sub3 {get; private set;}
}

public class SubControl : Canvas { // Can be any user control, I just happen to use a Canvas
public int Property1 {get; set;}
public string Property2 {get; set;}
}

What I would like to do is change the code so that the properties of the the SubControl's are editable in XAML. I'm aiming for something along the lines of:

<bbb:MainControl x:Name="abc">
<bbb.MainControl.Sub1 Property1="5" Property2="Hello"/>
<bbb.MainControl.Sub2 Property1="6" Property2="Goodbye"/>
</bbb:MainControl>

I have played around making the properties of SubControl DPs, as well as making each of the SubControl's DPs, but I keep getting error MC3057. The only way I have been able to get it to work is to add DPs to the MainControl for each of the properties of the SubControl, and bind them together. That's kind of ugly and scales poorly. Does anybody have any suggestions?

Re: WPF UserControl design question

Leung Yat Chun9-May-10 6:26

Leung Yat Chun

9-May-10 6:26

The proper syntax :

public class MainControl : UserControl {
   public SubControl Sub1 {get; set;}
}

<bbb:MainControl x:Name="abc">
   <bbb.MainControl.Sub1>
     <SubControl x:Name="Sub1" Property1="5" Property2="Hello" />
   </bbb.MainControl.Sub1>
</bbb:MainControl>

If you want to change it in run time you have to use Trigger.

For more information, please read WPF: A Beginner's Guide - Part 1 of n[^]

Regards
Joseph Leung

QuickZip

Re: WPF UserControl design question

Alex Barry10-May-10 2:10

Alex Barry

10-May-10 2:10

I was kind of hoping to avoid allowing a set on the SubControl properties. Allowing the consumer to change these properties would require unhooking and rehooking events, reinitializing the new property, etc. Maybe I'm just being lazy, but I was hoping that I could make the XAML manipulate the existing instances instead of creating new ones and hooking them up.

As for updating properties at run time, I would probably use code behind to update the properties.

Re: WPF UserControl design question

Leung Yat Chun10-May-10 2:38

Leung Yat Chun

10-May-10 2:38

This may work, but not too maintainable.

<UserControl.Triggers>
               <EventTrigger RoutedEvent="FrameworkElement.Loaded">
                   <BeginStoryboard>
                       <Storyboard>
                           <ObjectAnimationUsingKeyFrames BeginTime="0:0:0"  Storyboard.TargetProperty="Background">
                               <DiscreteObjectKeyFrame KeyTime="0:0:0" Value="Red" />
                           </ObjectAnimationUsingKeyFrames>
                       </Storyboard>
                   </BeginStoryboard>
               </EventTrigger>
           </UserControl.Triggers>

If you going to make DependencyProperty, you can inherit from current properties

public static readonly DependencyProperty OrientationProperty =
            VirtualWrapPanel.OrientationProperty.AddOwner(typeof(VirtualWrapPanelView));

Then Bind them in Xaml.

Regards
Joseph Leung

QuickZip

ViewModels and Threading issues..

daniel radford6-May-10 4:10

daniel radford

6-May-10 4:10

I have a large view model which can take several seconds to construct. The view model contains many ObservableCollections which only support changes from the UI thread. This forces me to construct the view model on the UI thread which causes the UI to hang for the duration of the construction time. It would be far nicer if I could do this on a background thread and display a progress dialog while it completes. Is there a way that I could achieve this?

Thanks for your help!
Dan

Re: ViewModels and Threading issues..

Abhinav S6-May-10 20:22

Re: ViewModels and Threading issues..

6-May-10 20:22

daniel radford wrote:
Is there a way that I could achieve this?

Maybe this link can help you implement loading on a background thread.

daniel radford7-May-10 3:30

daniel radford

7-May-10 3:30

That looks like just the thing.. thanks!

giving multiple groups different access in a silverlight application

Michael J. Eber5-May-10 7:59

Michael J. Eber

5-May-10 7:59

I have a silverlight 3.0 application which is a business data editor.
Up until now I've had only a single group accessing the application and that works just fine. I applied group policies to the folder the application lives in.

Now I am about to publish two editors that open the application up to two other groups. Our company is an ISO company and I have to implement security as follows:

            MainProgram -- all groups have access

EditorA  EditorB  EditorC  EditorD  EditorE  EditorF
RW GrpA  RW GrpA  RW GrpA  RW GrpA  RW GrpA  RW GrpA
R  GrpB  R  GrpB  -- GrpB  -- GrpB  RW GrpB  -- GrpB
R  GrpC  R  GrpC  -- GrpC  -- GrpC  -- GrpC  RW GrpC

For the editors that group b and c do not have access to, I should be able to limit access within the menu. But does anyone have suggestions as to how I manage the readonly right for the groups in the other editors?

Thanks,

Michael

Re: giving multiple groups different access in a silverlight application

Abhinav S6-May-10 4:37