Xamarin Forms Couldn't recognize telerik UI

8 posts, 0 answers
  1. San
    San avatar
    4 posts
    Member since:
    May 2018

    Posted 28 Jun 2018 Link to this post

    Hi,

     

    Xamarin forms dependency donesn't recognize in telerik UI 

    Error : 'telerikPrimitives' is an undeclared prefix. Line 20, position 10.
    Error : 'telerikInput' is an undeclared prefix. Line 24, position 14.

    Please provide me a solution.

     

    Thanks.

  2. Lance | Technical Support Engineer, Principal
    Admin
    Lance | Technical Support Engineer, Principal avatar
    861 posts

    Posted 28 Jun 2018 Link to this post

    Hi San,

    Those are XAML xmlns declarations. You need to have them defined at the top of the XML for any class that is not in the same scope as that XAML page. .

                 xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
                 xmlns:local="clr-namespace:YourApplicationNamespace.Portable"
                 xmlns:YOUR_XML_NAMEPSACE="clr-namespace:NAMESPACE;assembly=ASSEMBLY"
                 x:Class="RowStyleDemo.Portable.MainPage">


    For Telerik namespaces, you'll find them in the Getting Started section of the controls you're using. For example "telerikInput" can be seen in RadNumericInput Getting Started article and the telerikPrimitives can be seen in the RadBorder Getting Started article.


    Note that these can be whatever you want them to be, for example:

    <ContentPage x:Name="Page"
        xmlns:myAwesomeInput="clr-namespace:Telerik.XamarinForms.Input;assembly=Telerik.XamarinForms.Input"
        xmlns:myAwesomePrimitives="clr-namespace:Telerik.XamarinForms.Primitives;assembly=Telerik.XamarinForms.Primitives">
     
        <myAwesomeInput:RadNumericInput  />
     
        <myAwesomePrimitives:RadBorder />
     
    </ContentPage>

    If you're still having trouble, please reply back with the rest of the code so that I can inspect it directly.

    Regards,
    Lance | Tech Support Engineer, Sr.
    Progress Telerik
    Do you want to have your say when we set our development plans? Do you want to know when a feature you care about is added or when a bug fixed? Explore the Telerik Feedback Portal and vote to affect the priority of the items
  3. San
    San avatar
    4 posts
    Member since:
    May 2018
  4. Taqwa
    Taqwa avatar
    3 posts
    Member since:
    May 2018

    Posted 07 Nov 2018 in reply to Lance | Technical Support Engineer, Principal Link to this post

    I need your help please,

     

    I'm trying to add button but each time this error appear to me 

    xmlns:telerikInput="clr-namespace:Telerik.XamarinForms.Input;assembly=Telerik.XamarinForms.Input"

    please see attached.

     

    while I added the namespace on the top of xaml page

    xmlns:telerikInput="clr-namespace:Telerik.XamarinForms.Input;assembly=Telerik.XamarinForms.Input"

     

  5. Lance | Technical Support Engineer, Principal
    Admin
    Lance | Technical Support Engineer, Principal avatar
    861 posts

    Posted 07 Nov 2018 Link to this post

    Hello Taqwa,

    The namespace is correct. The likely issue is a missing the assembly references or the project doesn't have the NuGet package installed.

    Option 1 - Assembly References

    Please visit the RadButton's Getting Started > Required Telerik Assemblies article to make sure that all the assembles are referenced in each of the projects.


    Option 2 - NuGet (recommended in VS for Mac)

    The best way to ensure all of the projects have the appropriate references is to use the Telerik NuGet server instead of assembly references. Follow the instructions in that link and make sure you have the Telerik.UI.for.Xamarin NuGet package installed to all the projects.


    Demo

    Once you've added Telerik NuGet server to Visual Studio's NuGet package sources, you can use my attached demo to see the RadButton in action.

    For your convenience, here's the code on MainPage:

    <?xml version="1.0" encoding="utf-8"?>
    <ContentPage
        xmlns:telerikInput="clr-namespace:Telerik.XamarinForms.Input;assembly=Telerik.XamarinForms.Input"
        xmlns:local="clr-namespace:TaqwaDemo"
        x:Class="TaqwaDemo.MainPage">
        <Grid>
            <StackLayout
                VerticalOptions="Center"
                HorizontalOptions="Center"
                Orientation="Horizontal"
                Spacing="5">
                <telerikInput:RadButton
                    WidthRequest="120"
                    HeightRequest="120"
                    Text="A"
                    FontSize="Micro"
                    TextColor="White"
                    BackgroundColor="DarkMagenta"
                    CornerRadius="60" />
                <telerikInput:RadButton
                    WidthRequest="120"
                    HeightRequest="120"
                    Text="B"
                    FontSize="Micro"
                    TextColor="White"
                    BackgroundColor="DarkRed"
                    CornerRadius="60" />
                <telerikInput:RadButton
                    WidthRequest="120"
                    HeightRequest="120"
                    Text="C"
                    FontSize="Micro"
                    TextColor="White"
                    BackgroundColor="DarkBlue"
                    CornerRadius="60" />
            </StackLayout>
        </Grid>
    </ContentPage>


    Further Assistance

    If you have any future issues, please provide us with a way to reproduce the problem. The best way is sharing the project itself so we can investigate directly. Especially in cases where assemblies or NuGet packages are not working.

    If you're not able to share the entire project, then please share the code for that ContentPage along with the .csproj files from the relevant projects.

    Regards,
    Lance | Tech Support Engineer, Sr.
    Progress Telerik
    Do you want to have your say when we set our development plans? Do you want to know when a feature you care about is added or when a bug fixed? Explore the Telerik Feedback Portal and vote to affect the priority of the items
  6. Taqwa
    Taqwa avatar
    3 posts
    Member since:
    May 2018

    Posted 11 Nov 2018 in reply to Lance | Technical Support Engineer, Principal Link to this post

    Hello Eng.Lance,

     

    Thanks for your response.

    I followed the two option but still iOS project has the same issue.

    I upload the project in one drive

     https://ksauhsedu-my.sharepoint.com/:u:/g/personal/dwaibt_ksau-hs_edu_sa/EfuCRQVmv19Fm_x4Qgnosl4BFKtOsACVJmCeI_fKHw6yZQ?e=PLf8s3

     

    please help.

    thanks,

  7. Lance | Technical Support Engineer, Principal
    Admin
    Lance | Technical Support Engineer, Principal avatar
    861 posts

    Posted 11 Nov 2018 Link to this post

    Hello Taqwa,

    Thank you for providing the repro project. There were two things in the project that could cause this:

    1 - The Forms project was a PCL, this is a deprecated project type. All Xamarin.Forms apps (v3.x or later) should be using .NET Standard 2.0 

    Note: As I mentioned in our support ticket, the Telerik project template still uses a PCL, which is an error on our part. We needed to update this to .NET Standard 2.0 for our 2018 R3 release. This is going to be fixed in the next release.

    2 - There was some ambiguity because the Telerik assemblies were still in the project and there were some NuGet references and local assembly references. A duplicate assembly reference will provide duplicate namespaces and cause such an error.


    Solution

    Here is how you should create a new project until we update the project template for Mac

    1- Use the default Xamarin.Forms project template to create a new project
    2 - Add the Telerik to the solution by installing the Telerik.UI.for.Xamarin NuGet package to each project in the solution.

    Done!

    Demo

    I have gone ahead and done this for you and copied over the content in your original project. Find it attached. Here's a screenshot at runtime:



    Zip Tip

    Before I conclude, I wanted to share a tip when it comes to zipping up your project to be shared. You can delete all the bin, obj (and if your project has one, the Packages) folder from every project in the solution. This is because Visual Studio will create and restores these folders when you do a rebuild.  

    By removing these autogenerated folders, you reduce the ZIP size from hundreds of MBs down to just a few MB! For example, your project ZIP was 621 MB, while mine is now only 1 MB!


    Further Assistance

    I hope this is helpful, if you have any future trouble, please open a support ticket so we can investigate directly (you can attach a ZIP to a support ticket).

    Regards,
    Lance | Tech Support Engineer, Sr.
    Progress Telerik
    Do you want to have your say when we set our development plans? Do you want to know when a feature you care about is added or when a bug fixed? Explore the Telerik Feedback Portal and vote to affect the priority of the items
  8. Taqwa
    Taqwa avatar
    3 posts
    Member since:
    May 2018

    Posted 12 Nov 2018 in reply to Lance | Technical Support Engineer, Principal Link to this post

    Thanks Alot its working now, after using the xamarin template and installing telerik nuget package.
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