Re: (WPF) If Xaml That powerful? in real? - WPF Discussion Boards

Hi I am trying to achieve tricky binding behaviour from a treeview. I have a hierarchy of objects with the same base type. Some of these objects are of a derived 'leaf' type. I want to display the object hierarchy in a tree view with the leaf objects having a different data template from the rest of the branch objects.

The tricky thing I want to achieve is for the treeview to ignore all branches that do not have leaf objects in their subtree e.g. in this hierarhcy:

item1 - item3
_____- item4 - item6 - leaf1
__________________- leaf2
____________- item7

item3 and item7 would not be displayed as they have no leaves in their subtree.

Can this be achieved in XAML?

Thanks
Dan

I suggest you do that in MVVM. Here is an excellent article[^] describing how to use MVVM with a TreeView.

Eslam Afifi

I have taken your advice and written a view model layer which wraps my objects. However, I still have a problem:

All of the child lists of my underlying node objects are observable i.e. children can be added or removed at any time and the treeview needs to update. This means that a previously leafless node may suddenly gain a leaf in its subtree and so need to become visible. This means that I cannot simply cull leafless branches of the view model node tree - they need to be present but invisible in the tree view until a leaf is added. I have added a property 'HasLeavesInSubtree' to each tree node view model but have no idea how to use this in XAML to turn the display of these nodes on and off.

Thanks
Dan

Use a DataTrigger and set the visibility based on this.

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

My blog | My articles | MoXAML PowerToys | Onyx

Hi ,

I added <Image> // included an image in the window.</Image>

If I wish to add a label just below the image and few other controls, how can i do it? The XAML Code is shown here.

<Window x:Class="Window1"
      xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
      xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
      Height="Auto" Width="Auto" Loaded="Window_Loaded" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch">

            <Image
                  Name="imgClientPhoto"
                  HorizontalAlignment="Left"
                  VerticalAlignment="Top"
                  Width="auto"
                  Height="auto"
                  Grid.Column="0"
                  Grid.Row="0"
                  Margin="0" Source="D:\pic1.gif" MinWidth="450" MinHeight="100" Grid.IsSharedSizeScope="True">

            </Image>
      <Label>

      </Label>


</Window>

I added <Label></Label>just below the   <Image>

but an error is seen "The property "content" is set more than once.

Please help me to correct this error.

My intention is to add an image at the top(title), then below it a label,then a dropdown box, treeview.. so on..

Please help the good way to work on this.

Thanks Ramm

You need to put a container into your window to handle multiple items - effectively, the content of your window is the image and you have added extra items immediately after. There are many containers available, e.g. Grid, StackPanel, UniformGrid and so on. The one you use is based on how you want to lay out your interface.

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

My blog | My articles | MoXAML PowerToys | Onyx

HI ALL
I was considering and trying to Import sophisticated Designs as Xaml in a Project of WPF
I was Working with AI and also Tried MS Expression Design
==========
1) about AI
I tried to use a Plug-in to export Xaml files, but when you have complicated images it just change that image to a simple image , I had a 3D effect on my Design , but it was simplified by the plug-in i used
and just a very simple image had been made
==========
2) about Expression Design
It didn't have any Effect, the only thing that you have is Gradient, as I saw
and it is not enough to have a professional design
=============
Conclusion: I think The Xaml or at least Xaml Generator are not that powerful to produce complicated, professional designs
================
I want to tell me if it is really rigt or wrong
and if I had mistake in part 1 and/or 2 tell me if there are other tools, plug-ins , and etc
Thank you

Am I banned to write message?
Does anybody see my post?
or is there any problem that I don't get any answer?

modified on Wednesday, July 15, 2009 5:28 AM

cppwxwidgetsss wrote:
I tried to use a Plug-in to export Xaml files, but when you have complicated images it just change that image to a simple image , I had a 3D effect on my Design , but it was simplified by the plug-in i used
and just a very simple image had been made

Expression imports AI files. You need to break them into components to create controls. It doesn't just magically create UI for you. Also, by default it creates a PNG, not XAML, and you should play with the options to create XAML as you need it.

cppwxwidgetsss wrote:
It didn't have any Effect, the only thing that you have is Gradient, as I saw
and it is not enough to have a professional design

Expression creates XAML, XAML has gradients, what other effects were you hoping for ?

cppwxwidgetsss wrote:
I think The Xaml or at least Xaml Generator are not that powerful to produce complicated, professional designs

A professional design should not be complicated. I've written several programs with WPF, and the UIs on them all are excellent. We had a graphic designer create designs for us in AI, and for one program I skinned with bitmaps, but nowadays I export XAML from AI files. Our designer is given total freedom, which is often a lot of work for me, in terms of non standard shapes etc, but I have NEVER had any trouble turning his screenshots into UI that is identical or better.

cppwxwidgetsss wrote:
Am I banned to write message?
Does anybody see my post?
or is there any problem that I don't get any answer?

It's a free website and you posted while the USA ( where most users are ) was asleep. If I was home in Australia, you'd have got a reply. It's now 6 am and I am up early. If you want instant answers, find someone in your timezone you can pay to be on call. Otherwise, you just have to wait until someone replies.

Christian Graus

Driven to the arms of OSX by Vista.

Read my blog to find out how I've worked around bugs in Microsoft tools and frameworks.

cppwxwidgetsss wrote:
Am I banned to write message?

Unfortunately, no...

cppwxwidgetsss wrote:
Does anybody see my post?

Unfortunately, yes.

BTW, set the right country in your profile. It's REAL obvious you're not from the US.

As to your question, you can do pretty much anything you can dream up with WPF. You just have to learn how, and there are no shortcuts in the learning process.

"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." - Jason Jystad, 10/26/2001

cppwxwidgetsss wrote:
Conclusion: I think The Xaml or at least Xaml Generator are not that powerful to produce complicated, professional designs

That is not correct - WPF allows you to produce extremely professional designs, perhaps it's your lack of artistic ability that's getting in the way.

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

My blog | My articles | MoXAML PowerToys | Onyx

Pete O'Hanlon wrote:
perhaps it's your lack of artistic ability that's getting in the way.

LOL - as I said, we have a graphic designer, if we didn't, that would sure be our main problem....

Christian Graus

Driven to the arms of OSX by Vista.

Read my blog to find out how I've worked around bugs in Microsoft tools and frameworks.

cppwxwidgetsss wrote:
I want to tell me if it is really rigt or wrong

I'm going with wrong.

XAML and XAML generators do NOT produce "complicated, professional designs"...designers do.

In fact, nothing in your post has anything to do with XAML...

You may want to try out Expression Blend 3[^], which supposedly now imports
PSD/AI files preserving the layers and allowing editing in Blend.

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Hi,
I wrote a class inherting from canvas. I added a child inside ItemTemplate.I am having a linkbutton as child. I added it in Page.xaml as

<my:parent><br />
 <my:DataPoint Text="30 Members" Link="http://www.zsl.com" ImageUrl="../images/chat.png"></my:DataPoint><br />
</my:parent>

What i want now is,if i change the text or link value it should reflect in design view. Any Idea about this!

Gomathi R

modified on Tuesday, July 14, 2009 5:24 AM

Hello,

I think it would be better if you can show us some of your code. Otherwise, it's hard for us to help you to solve your problem.

Thanks and Regards,
Michael Sync ( Blog: http://michaelsync.net)

Microsoft MVP (Silverlight), WPF/Silverlight Insiders

How can i partially load the controls(combo box, list box) from database, Just like the AJAX's Update panel.
Thanks in advance

There are numerous ways that you could achieve this, and most of them revolve around using databinding. Take a look at the MVVM pattern to get some ideas (you could start with my SongBird[^] article and look at how I bind and refresh my tabs).

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

My blog | My articles | MoXAML PowerToys | Onyx

hello
i installed the silverlight exe file
when i created the project there was no silverlight file
what happened

I'm not sure what you are asking.

Silverlight.exe installs the Silverlight runtime. That has nothing
to do with projects.

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

install Silverlight2_tools.exe

Message Removed

Don't tie yourself in knots trying to use XAML. Just write code to trigger the animation when you want it to run

Christian Graus

Driven to the arms of OSX by Vista.

Read my blog to find out how I've worked around bugs in Microsoft tools and frameworks.

Hi,

I'm currently struggling with the WPF Toolkit's DataGrid. Well just one aspect to be more accurate. I am displaying the properties of an object in their own columns on the datagrid and each property is bound to a DatagridTextColumn. But if I add a new column after the object has been instanciated and I bind to another property of the object, the binding doesn't work. The datagrid throws a NullRefferenceException. How can I work around this without having to reinstanciate the object?

can you post your code...

OK,

This is the XAML for the Datagrid:

<my:DataGrid CanUserAddRows="True" RowHeaderWidth="10" CanUserResizeRows="False" Margin="235,344,38,93" RowHeaderStyle="{StaticResource RowHeaderStyle}" ColumnHeaderStyle="{StaticResource ColumnHeaderStyle}" HeadersVisibility="All" Name="TenderDataGrid" ItemsSource="{Binding Path=TenderLineItems}" AutoGenerateColumns="False" ColumnWidth="SizeToHeader" IsReadOnly="False" SelectionChanged="TenderDataGrid_SelectionChanged" CanUserSortColumns="False" SelectionMode="Single" SelectionUnit="CellOrRowHeader" IsSynchronizedWithCurrentItem="True" Background="#FFDDDDDD" BorderBrush="#FFAAAAAA" BorderThickness="3" AlternatingRowBackground="LightBlue">
     <my:DataGrid.Columns>
                              <my:DataGridTextColumn Header="Series" Binding="{Binding Path=Series, Mode=TwoWay}" Width="Auto"></my:DataGridTextColumn>
                              <my:DataGridTextColumn Header="Item No" Binding="{Binding Path=ItemNo, Mode=TwoWay}"></my:DataGridTextColumn>
                              <my:DataGridTextColumn Header="Description" Binding="{Binding Path=Description, Mode=TwoWay}" MinWidth="200"></my:DataGridTextColumn>
                              <my:DataGridTextColumn Header="Unit" Binding="{Binding Path=Unit, Mode=TwoWay}"></my:DataGridTextColumn>
                              <my:DataGridTextColumn Header="Quantity" Binding="{Binding Path=Qty, Mode=TwoWay}"></my:DataGridTextColumn>
                              
                        </my:DataGrid.Columns>
                  </my:DataGrid>

(Sorry about the indentation)

I have a class that defines an observable collection:

using System.Collections.ObjectModel;
using MMSDLL;

namespace Tender_Module
{
      class TenderItemModel
      {
            public ObservableCollection<ITenderLineItem> TenderLineItems {get;set;}

      }
}

This is the interface that I use to be able to add Items to the grid:

using System;
using System.Collections.Generic;
using System.Collections;
using System.Linq;
using System.Text;

namespace MMSDLL
{
      public interface ITenderLineItem
      {
            int RateSize { get; set; }
            string Series { get; set; }
            string Description { get; set; }
            string ItemNo { get; set;}
            string Unit { get; set; }
            double? Qty { get; set; }
            double Rate1 { get; set; }
            double Rate2 { get; set; }
            double Rate3 { get; set; }
            double Rate4 { get; set; }
            double Rate5 { get; set; }
            double Rate6 { get; set; }
            double Rate7 { get; set; }
            double Rate8 { get; set; }
            double Rate9 { get; set; }
            double Rate10 { get; set; }
            double Rate11 { get; set; }
            double Rate12 { get; set; }
            double Rate13 { get; set; }
            double Rate14 { get; set; }
            double Rate15 { get; set; }
            double Rate16 { get; set; }
            double Rate17 { get; set; }
            double Rate18 { get; set; }
            double Rate19 { get; set; }
            double Rate20 { get; set; }
            double Rate21 { get; set; }
            double Rate22 { get; set; }
            double Rate23 { get; set; }
            double Rate24 { get; set; }
            double Rate25 { get; set; }
            double Rate26 { get; set; }
            double Rate27 { get; set; }
            double Rate28 { get; set; }
            double Rate29 { get; set; }
            double Rate30 { get; set; }
            double Rate31 { get; set; }
            double Rate32 { get; set; }
            double Rate33 { get; set; }
            double Rate34 { get; set; }
            double Rate35 { get; set; }
            double Rate36 { get; set; }
            double Rate37 { get; set; }
            double Rate38 { get; set; }
            double Rate39 { get; set; }
            double Rate40 { get; set; }
      }
}

Then on my main Window where I define the DataGrid, This is the code I use to set the DataContext:

using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Text;
using System.Data;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using SYSTEM_LIB_DLL;
using SYSTEM_LIB_DLL.Entity;
using Microsoft.Windows.Controls;
using MMSDLL;

namespace Tender_Module
{
      /// <summary>
      /// Interaction logic for Window1.xaml
      /// </summary>
      public partial class Window1 : Window
      {
            private ObservableCollection<ITenderLineItem> LineItems = new ObservableCollection<ITenderLineItem>();
            private TenderItemModel TM;
            private Tender InstanceTender;
            private const string COMPANY_NAME = "Infrastructure Systems Integrators - Tender Module";
            private int seriesPosition = 0;
            private string operation;
            private RateHandler InstanceRateHandler = null;

            public RateHandler CurrentRateHandler
            {
                  get
                  {
                        return InstanceRateHandler;
                  }
                  set
                  {
                        InstanceRateHandler = value;
                  }
            }

            public Window1()
            {
                  InitializeComponent();
                  this.Title = COMPANY_NAME;
                  TM = new TenderItemModel { TenderLineItems = LineItems };
                  TenderDataGrid.DataContext = TM;
                  MainGrid.Visibility = Visibility.Hidden;
            }

This is just the first part of a very large class so I'm leaving out the rest of the class and I'll just show the relevant methods that I use:

Now after i've added a few ITenderLineItems to the grid, i want to add new columns to the grid and set their bindings.

            private void CreateRateColumns(int numColumns)
            {

                  for (int i = 1; i <= numColumns; i++)// Iterate numColumns
                  {

                              DataGridTextColumn RateColumn = new DataGridTextColumn();
                              Binding theBinding = new Binding("Rate" + i);
                              RateColumn.Binding = theBinding;
                              RateColumn.Header = "Rate " + i + " ";
                              RateColumn.IsReadOnly = false;
                              TenderDataGrid.Columns.Add(RateColumn);
                  }
            }

This method is relatively straightforward but what happens is that the bindings don't work on the Datagrid after it has been populated with ITenderLineItems instances. If I create the columns before adding these objects to it, then all is well. Now I'm getting a NullReferenceException on the grid if i enter a text value in one of these Dynamicly created columns' cells. I need this grid to adapt to the settings that the user change as long as the program is running. This is quite a thorn in my flesh

Hi,
I'm newish to threading & asynchronous development so please bear with me if this is a bit of a n00b question. I would like to cache my proxy client object (in my case called DataServiceClient) to prevent constructing the same class over and over with each data read but I'm thinking that doing this in an async architecture could cause problems (playing with Silverlight, not enjoying the learning curve).

When I subscribe to the response event in my cached object, how would I unsubscribe that specific instance of my method call? Subscribing to events do not give you a unique handle for that subscription, and unsubscribing based on method signature could cause problems as I could use the same method for different things...

Could anonymous methods work for this? Do I need to unsubscribe anonymous methods?

How do I manage the user browsing away form my window before my response event fires (rending my data target non-existent)?

Is there a concise article on the web that I need to read before asking this?

(I really wish they would bring sync calls into Silverlight, I have argued with a number of async fans, and I NEED sync calls)

____________________________________________________________
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