Questions on UI for WPF Forum

1 answer

113 views

Hi,

I have for example following GridView:

            <telerik:RadGridView x:Name="gvSystems" Grid.Row="1" Grid.Column="0" DataContext="{Binding}" ItemsSource="{Binding Systems}" AutoGenerateColumns="False"
                             ShowSearchPanel="False" ShowGroupPanel="False" ShowGroupFooters="False" IsFilteringAllowed="True" FilteringMode="FilterRow" IsReadOnly="True" GroupRenderMode="Flat"
                                 SelectionMode="{Binding QueryFilterModel.MultiSelectSystems, Converter={StaticResource BoolToSelectionModeConverter}}" Margin="3" CanUserSortColumns="True">
                <telerik:RadGridView.Columns>
                    <telerik:GridViewDataColumn IsSortable="True" Header="{Binding Path=[VXScada_GernericQueries_GridView_ID], Source={x:Static commonUIRes:TextContainer.Instance}}" DataMemberBinding="{Binding SystemID}" />
                    <telerik:GridViewDataColumn IsSortable="True" Header="{Binding Path=[VXScada_GernericQueries_GridView_Name], Source={x:Static commonUIRes:TextContainer.Instance}}" DataMemberBinding="{Binding SystemName}" />
                </telerik:RadGridView.Columns>
            </telerik:RadGridView>

If I click into the header to sort my application crashes with following Exception (This happens with each RadGridView I have):

System.NullReferenceException

Source: Telerik.Windows.Data

StackTrace:

   bei Telerik.Windows.Data.QueryableCollectionView.InternalGetItemAt(Int32 index)
   bei Telerik.Windows.Data.QueryableCollectionView.GetItemAt(Int32 index)
   bei Telerik.Windows.Data.DataItemCollection.get_Item(Int32 index)
   bei Telerik.Windows.Controls.GridView.Rows.GetRowItemsAtRange(Int32 startIndex, Int32 endIndex)
   bei Telerik.Windows.Controls.GridView.GridViewVirtualizingPanel.FlatLayoutStrategy.RealizeRows(Int32 startIndex, Int32 endIndex, Double& verticalOffset, HashSet`1& realizedRows)
   bei Telerik.Windows.Controls.GridView.GridViewVirtualizingPanel.FlatLayoutStrategy.MeasureOverride(Size availableSize)
   bei Telerik.Windows.Controls.GridView.GridViewVirtualizingPanel.MeasureOverride(Size availableSize)
   bei System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   bei System.Windows.UIElement.Measure(Size availableSize)
   bei System.Windows.ContextLayoutManager.UpdateLayout()
   bei System.Windows.ContextLayoutManager.UpdateLayoutCallback(Object arg)
   bei System.Windows.Media.MediaContext.FireInvokeOnRenderCallbacks()
   bei System.Windows.Media.MediaContext.RenderMessageHandlerCore(Object resizedCompositionTarget)
   bei System.Windows.Media.MediaContext.RenderMessageHandler(Object resizedCompositionTarget)
   bei System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   bei System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
   bei System.Windows.Threading.DispatcherOperation.InvokeImpl()
   bei MS.Internal.CulturePreservingExecutionContext.CallbackWrapper(Object obj)
   bei System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   bei System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   bei System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   bei MS.Internal.CulturePreservingExecutionContext.Run(CulturePreservingExecutionContext executionContext, ContextCallback callback, Object state)
   bei System.Windows.Threading.DispatcherOperation.Invoke()
   bei System.Windows.Threading.Dispatcher.ProcessQueue()
   bei System.Windows.Threading.Dispatcher.WndProcHook(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   bei MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   bei MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
   bei System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   bei System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
   bei System.Windows.Threading.Dispatcher.LegacyInvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs)
   bei MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam)
   bei MS.Win32.UnsafeNativeMethods.DispatchMessage(MSG& msg)
   bei System.Windows.Threading.Dispatcher.PushFrameImpl(DispatcherFrame frame)
   bei System.Windows.Application.RunDispatcher(Object ignore)
   bei System.Windows.Application.RunInternal(Window window)

GridView

answered on 01 Feb 2017

1 answer

187 views

prevent validation on firing on empty cells

hi dera all,

i have binded a table to the gridview. now, the grid cell for example double type, errors when the user left it empty and does not let user to go to the other cells. i do not need it.

i need to user to freely go to the different cells and only caugh on the inputting wrong datatype forexample inputting string instead of double (not lefting a double cell empty). how can i disable built in validation for this?

also i need to check the cells manually and under certain circumestances, change the color of dell border to be red and else black. what does you suggest?

best regards.

GridView

answered on 01 Feb 2017

1 answer

596 views

Filtering of GridViewComboBoxColumn using enums and DisplayMemberPath

Hi @ll,

I need your help. After searching the internet for several hours I have
no solution for my problem.

I have an enum property which I bind to a GridViewComboBoxColumn
using the following xaml code:

<telerik:GridViewComboBoxColumn ItemsSourceBinding="{Binding Options}"

DataMemberBinding="{Binding Position}"

DisplayMemberPath="Value"

SelectedValueMemberPath="Key"/>

Options is a property which maps the enum value to a string:

public enum Pos

{

A, B, C

}

public class DisplayObject<T>

{

private readonly T key;

private readonly string val;

public DisplayObject(T key, string val)

{

this.key = key;

this.val = val;

}

public T Key => this.key;

public string Value => this.val;

}

public IEnumerable<DisplayObject<Pos>> Options

{

get

{

yield return new DisplayObject<Pos>(Pos.A, "HUGO");

yield return new DisplayObject<Pos>(Pos.B, "EGON");

yield return new DisplayObject<Pos>(Pos.C, "WILLI");

}

Grid works fine. But there are some problems with the FilteringControl.

I want the FilteringControl to uses the DisplayMemberPath to display
the DistinctValues and ComboBox Options.

Can anyone help me solving my problem?

public class Item : INotifyPropertyChanged

{

private Pos pos;

private string name;

public Item(string name, Pos pos)

{

this.name = name;

this.pos = pos;

}

public string Name

{

get

{

return this.name;

}

public Pos Position

{

get

{

return this.pos;

}

set

{

if (this.pos == value)

{

return;

}

this.pos = value;

this.OnPropertyChanged(nameof(this.Position));

}

public IEnumerable<DisplayObject<Pos>> Options

{

get

{

yield return new DisplayObject<Pos>(Pos.A, "HUGO");

yield return new DisplayObject<Pos>(Pos.B, "EGON");

yield return new DisplayObject<Pos>(Pos.C, "WILLI");

}

public event PropertyChangedEventHandler PropertyChanged;

[NotifyPropertyChangedInvocator]

protected virtual void OnPropertyChanged(string propertyName)

{

this.PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));

}

<Window x:Class="ChangeDefaultFilterOperator.MainWindow"

xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation"

xmlns:my="clr-namespace:ChangeDefaultFilterOperator"

Title="MainWindow" Height="700" Width="700">

<Window.Resources>

<my:MyViewModel x:Key="MyViewModel"/>

</Window.Resources>

<Grid DataContext="{StaticResource MyViewModel}">

<telerik:RadGridView ItemsSource="{Binding Items}"

AutoGenerateColumns="False"

Margin="5">

<telerik:RadGridView.Columns>

<telerik:GridViewDataColumn DataMemberBinding="{Binding Name}"/>

<telerik:GridViewComboBoxColumn ItemsSourceBinding="{Binding Options}"

DataMemberBinding="{Binding Position}"

DisplayMemberPath="Value"

SelectedValueMemberPath="Key"/>

</telerik:RadGridView.Columns>

</telerik:RadGridView>

</Grid>

</Window>

public class MyViewModel

{

private readonly ObservableCollection<Item> items;

public MyViewModel()

{

this.items = new ObservableCollection<Item>

{

new Item("AAA", Pos.A),

new Item("BBB", Pos.B),

new Item("CCC", Pos.C)

};

}

public ObservableCollection<Item> Items

{

get

{

return this.items;

}

GridView

answered on 01 Feb 2017

0 answers

111 views

Question about adding a button and MVVM

Hello All,

I am using WPF and MVVM. I have a observable collection of objects that I am displaying in the grid. I am trying to add a new column at the beginning of the gridview that has a button in it . This button needs to fire off a command in my ViewModel. In the command's execute method, I need to edit some of the properties of the entity that that row represents in my observable collection. I am assuming that I'll need to pass some sort of parameter to the command to send in either the row contents or some event args for the button being clicked... But I'm not exactly sure what I need to do. I would interested the most in doing this WITHOUT any code-behind in the View, and do this some way with the XAML and ViewModel code, trying to keep in the MVVM frame of mind... Any help will be greatly appreciated!

Thanks in advance,

Kevin Orcutt

GridView

asked on 31 Jan 2017

6 answers

166 views

ExportPDF Custom Command Descriptor Issue

Hello,

I have written a Custom Command Descriptor based on the Telerik demos and documentation that exports the currently loaded document to a local file. Everything appears to be working 100% correct with no errors. However, when I open the file all the pages are blank. The page count is correct, so it appears to be reading the PDFViewer document correctly into the stream, just not writing all of the bytes properly. Here is my code behind for the page that contains the Document Viewer control.

using System;

using System.IO;

using System.Windows;

using System.Windows.Controls;

using System.Windows.Input;

using Telerik.Windows.Documents.Fixed.FormatProviders;

using Telerik.Windows.Documents.Fixed.FormatProviders.Pdf;

using Telerik.Windows.Documents.Fixed.Model;

using WeldTrackingWPF.ViewModel;

using Telerik.Windows.Controls;

using Telerik.Windows.Documents.Commands.Descriptors;

using Telerik.Windows.Documents.Commands;

namespace WeldTrackingWPF.View

{

/// <summary>

/// Interaction logic for ViewQualificationDoc.xaml

/// </summary>

public partial class ViewDoc : Page

{

public ViewDoc(byte[] fileBytes)

{

InitializeComponent();

/// <summary>

/// Read bytes into memory stream

/// Pass stream in RadPdfViewer for viewing

/// </summary>

this.pdfViewer.CommandDescriptors = new CustomCommandDescriptors(this.pdfViewer);

Stream stream = new MemoryStream(fileBytes);

FormatProviderSettings settings = new FormatProviderSettings(ReadingMode.AllAtOnce);

PdfFormatProvider provider = new PdfFormatProvider(stream, settings);

RadFixedDocument doc = provider.Import();

this.pdfViewer.Document = doc;

IconSources.ChangeIconsSet(IconsSet.Modern);

}

private void Page_Initialized(object sender, EventArgs e)

{

var vm = new ViewDocViewModel();

DataContext = vm;

}

private void PdfViewer_DocumentLoaded(object sender, EventArgs args)

{

}

private void Page_Unloaded(object sender, RoutedEventArgs e)

{

}

private void tbCurrentPage_KeyDown(object sender, KeyEventArgs e)

{

TextBox textBox = sender as TextBox;

if (textBox != null)

{

if (e.Key == System.Windows.Input.Key.Enter)

{

textBox.GetBindingExpression(TextBox.TextProperty).UpdateSource();

}

public class SaveCommand : FixedDocumentViewerCommandBase

{

public SaveCommand(FixedDocumentViewerBase fixedDocumentViewerBase)

: base(fixedDocumentViewerBase)

{

}

public override void Execute(object parameter)

{

Microsoft.Win32.SaveFileDialog dialog = new Microsoft.Win32.SaveFileDialog();

dialog.Filter = "PDF files (*.pdf)|*.pdf";

bool? result = dialog.ShowDialog();

if (result.HasValue && result.Value)

{

using (Stream stream = File.OpenWrite(dialog.FileName))

{

PdfFormatProvider provider = new PdfFormatProvider();

provider.Export(this.Viewer.Document, stream);

}

public class CustomCommandDescriptors : DefaultCommandDescriptors

{

private readonly CommandDescriptor saveCommandDescriptor;

public CommandDescriptor SaveCommandDescriptor

{

get

{

return this.saveCommandDescriptor;

}

public CustomCommandDescriptors(FixedDocumentViewerBase fixedDocumentViewer) : base(fixedDocumentViewer)

{

this.saveCommandDescriptor = new CommandDescriptor(new SaveCommand(fixedDocumentViewer));

}

Any insight as to why these documents are being exported sans page content would be appreciated.

Thanks!

PDFViewer

answered on 31 Jan 2017

7 answers

230 views

Binding errors on viewDefinitions' titles

Hello,

I noticed some binding errors in my output window that I could not explain at first:

System.Windows.Data Warning: 40 : BindingExpression path error: 'Title' property not found on 'object' ''String' (HashCode=1191344071)'. BindingExpression:Path=Title; DataItem='String' (HashCode=1191344071); target element is 'ContentPresenter' (Name='Content'); target property is 'ResourceKey' (type 'String')

after some meddling around, I finally found out that what was causing those errors where the viewDefinitions in the ScheduleView object.

it appears that I always have as many binding errors as viewDefinitions, no matter how many viewDefinitions I add to the object. So I'm guessing something is wrong with the way the viewDefinition's Title property is bound in the template. (I add "blank" viewDefinitions, with nothing set, not even the title, and I get this error. NB: the title seems to be displayed correctly, though...)

can you confirm this? or is this something on my side that I have not understood ?

ScheduleView

answered on 31 Jan 2017

1 answer

110 views

Search as you type - dynamic objects

Hi everyone,
we use a collection with dynamic objects which is binded to a RadGridView.
All colums and rows are shown correctly but unfortunatly the integrated search function (ctrl + f) does not search within attributes which are added dyanmically to the objects.
It works only for attributes which are directly implemented.

Is it a common behaviour of the search function or may be a bug \ missing feature?

Thank you for your help!

GridView

answered on 31 Jan 2017

1 answer

362 views

Binding to DeleteButton Visibility

Hi my appointments have a active flag and when it's false, I would like the delete button to hide. I was reading that I should edit the schedule view xaml code but my bindings aren't correct. Any ideas?

<telerik:RadButton x:Name="DeleteButton"

Style="{StaticResource DeleteButtonStyle}"

Command="{x:Static local:RadScheduleViewCommands.DeleteAppointment}"

ClickMode="Press"

CommandParameter="{Binding RelativeSource={RelativeSource TemplatedParent}}"

Visibility="{Binding Active, Converter={StaticResource BooleanToVisibilityConverter}}"

IsTabStop="False" />

ScheduleView

answered on 31 Jan 2017

5 answers

219 views

Calculator Picker and decimal places

Is there a way to get the calculator picker to display 1.00 instead of just 1? I want to use it to display money values and 1.00 feels better than just 1.

Calculator

answered on 30 Jan 2017

3 answers

117 views

Error AsyncSqlGeospatialDataReader

Hi,

I have successfully used the AsyncSqlGeospatialDataReader to read shape data stored in a geometry column in SQL. I first read the geometry objects into a local collection and then assign that collection to the reader

var readerRail = new Telerik.Windows.Controls.Map.SqlGeospatialDataReader();

readerRail.Source = RailShapes;

readerRail.ToolTipFormat = "{SegmentLabel}";

readerRail.GeospatialPropertyName = "ShapeWKT";

readerRail.PreviewReadCompleted += readerRail_PreviewReadCompleted;

However, while this has worked on three previous collections on this specific one I get a "Non-static method requires a target" error. It seems as if some of the shape data must then be an issue but I have no idea where to start looking.

PS: SQL Management studio can query the data and display it

Map

answered on 30 Jan 2017