Hi!

I'm using WPF RadComboBox in an application and run the application on a Lenovo ThinkPad. It has touch screen and runs Windows 10 Enterprise.

When I have many items in my RadComboBox and scroll through them on the touch screen, the scroll is much too fast - it scrolls too many items at the time.

I installed the WPF Controls Demo and got the same result, though not as apparent since the example doesn't contains as many items.

Have you experienced the same problem? Is there any way I can "slow down" the scroll?

If I use a regular WPF ComboBox instead of the RadComboBox, I don't have this problem. But I'd really prefer to use the RadComboBox if possible =)

Best Regards!

In reference to: https://www.telerik.com/blogs/how-to-boost-radgridview-performance-for-wpf-and-silverlight-using-lightweight-templates

I just discovered your new TELERIK COLOR THEME GENERATOR. (very cool by the way :-)

1) Are the "CHOOSE THEME" items the lightweight templates ?

2) If the answer to 1) is yes, will modifying anything in the tool increase the "weight" ?

3)The "Office2016Touch" template is almost a perfect match to our current color scheme, so we'd likely go with that...is it "lightweight" ?

Thanks in advance,

Barry

Hi,

I'm running into some problems applying new style & template settings to AutoCompleteBox.

I've read this article: https://docs.telerik.com/devtools/wpf/styling-and-appearance/styling-apperance-editing-control-templates,and I've created a simple default Telerik application that has only an AutoCompleteBox defined:

<Window x:Class="TelerikWpfApp1.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"
                Title="MainWindow" Height="350" Width="525">
        <Grid>
            <telerik:RadAutoCompleteBox />   
        </Grid>
</Window>

If I use VS to generate a copy of the required template (i.e. right-click the RadAutoCompleteBox, Edit Template ->Edit a Copy..., etc., I get this error message:

InvalidCastException: [A]Telerik.Windows.Controls.RadListBox cannot be cast to [B]Telerik.Windows.Controls.RadListBox. Type A originates from 'Telerik.Windows.Controls, Version=2019.2.618.45, Culture=neutral, PublicKeyToken=5803cfa389c90ce7' in the context 'LoadNeither' at location 'C:\Users\WWill\AppData\Local\Microsoft\VisualStudio\16.0_789bb273\Designer\ShadowCache\gmfvgqnw.h3w\4sct5rze.jm2\Telerik.Windows.Controls.dll'. Type B originates from 'Telerik.Windows.Controls, Version=2019.2.618.45, Culture=neutral, PublicKeyToken=5803cfa389c90ce7' in the context 'LoadFrom' at location 'C:\Program Files (x86)\Progress\Telerik UI for WPF R2 2019\Binaries\WPFRadF45\Telerik.Windows.Controls.dll'.

If, instead, I open the Telerik.Windows.Controls.Input.xaml file and copy the relevant RadAutoCompleteBox styles/templates into a resource dictionary in my application, I find a great many dependencies on other definitions in that file, which triggers a lot of "not found" reference errors.

So, I copied the entire ResourceDictionary from that file into my test app. Not too happy about copying 7,500 lines of code anywhere, but, hey, I'll try anything once. Unfortunately, I'm still getting errors, this time 28 of them in the form:

Severity Code Description Project File Line Suppression State
Error XDG0044 The local property "Columns" can only be applied to types that are derived from "RadUniformGrid". TelerikWpfApp1 App.xaml 5334 

As these did not stop me from building/running my app, I proceeded to modify my RadAutoCompleteBox definition as follows:

<telerik:RadAutoCompleteBox TextBoxStyle="{DynamicResource RadAutoCompleteTextBoxStyle}"/> 

This resulted in the following message:

InvalidOperationException: 'RadWatermarkTextBox' TargetType does not match type of element 'RadWatermarkTextBox'.

Again, this error doesn't stop me from compiling/running the app, but I thought I'd mention it in case it's an indicator

Finally, despite all the aforementioned errors, I am able to tweak the appearance of my RadAutoCompleteBox control, but I'm not feeling too good about it, as it seems like a very inelegant way to achieve a few visual tweaks.

Any advice for a newbie?

Wayne

Hi!

I couldn't find any information about selecting which camera I want to use in RadWebCam. Any sample? Or is it not possible?

Also there should be a way to save and load the settings of a camera.Any hints?

Thanks

Why is performance so good for this control? I'm loading 23,000 search items into an ObservableCollection, and search response is almost instantaneous.

This may seem like an odd question, but in preparing to work with this control, I found a few online complaints about performance and a suggestion to trigger virtualization by setting the MaxHeight property of the inner ListBox, as follows:

<Style x:Key="AutoCompleteBoxStyle" TargetType="{x:Type toolkit:AutoCompleteBox}">
    <Style.Resources>
        <Style TargetType="{x:Type ListBox}">
            <Setter Property="MaxHeight" Value="200" />
        </Style>
    </Style.Resources>
</Style>

I found that this wasn't necessary, and as I hate mysteries, I'm wondering if Telerik has taken care of all performance issues (say by automatically triggering virtualization) since the time of the complaints.

If this isn't the case, and I can expect to run into performance problems with a larger number of search items, are there any standard techniques to address such eventual problems?

Wayne

Hello,

I'm trying to exclude some (but not all) RadGridView columns' information from being persisted using PersistenceManager.

For example, in the below grid, how would I exclude column Info's properties from being persisted based on the column's Header name (assume I've defined CustomPropertyProvider for the grid to persist properties like Width, Header, etc.)?

<telerik:RadGridView x:Name="TestGrid"
                     telerik:PersistenceManager.StorageId="TestGrid"
                     AutoGenerateColumns="False">
   <telerik:RadGridView.Columns>
      <telerik:GridViewDataColumn Header="Info" DataMemberBinding="{Binding Info}"/>
      <telerik:GridViewDataColumn Header="Data" DataMemberBinding="{Binding Data}"/>
   </telerik:RadGridView.Columns>
</telerik:RadGridView>

I could use SerializationOptions but I'm not sure what I'd put in the "Expression" field to exclude column "Info" (see below):
<telerik:PersistenceManager.SerializationOptions>
   <telerik:SerializationMetadataCollection>
      <telerik:PropertyNameMetadata Condition="Except" Expression="??" SearchType="PropertyName" />
   </telerik:SerializationMetadataCollection>
</telerik:PersistenceManager.SerializationOptions>